JP7393201B2 - Robots, humanoid robots, and robot fall control methods - Google Patents

Description

The present invention relates to a robot, a humanoid robot, and a method for controlling the fall of a robot, and particularly relates to a robot equipped with a motor that operates a dynamic brake, a humanoid robot, and a method for controlling the fall of the robot.

Conventionally, a synchronous electric motor (motor) in which a dynamic brake is activated during an emergency stop is known (see, for example, Patent Document 1).

Patent Document 1 described above includes a transistor module including a transistor (switching element) that drives a synchronous motor using a three-phase power supply of U, V, and W phases, and a braking force generated by dynamic brake using the transistor of the transistor module. A synchronous motor is disclosed that includes a dynamic brake control circuit that generates a dynamic brake control circuit, and a dynamic brake circuit that is connected to the output side of a transistor module and generates braking force by the dynamic brake using a resistor.

In this synchronous motor, at the initial stage of an emergency stop, the motor is decelerated by on/off control of a transistor (switching element) in a dynamic brake control circuit so that the current flowing through the motor is constant. Then, after the induced voltage decreases and the current flowing to the motor becomes no longer constant (from the point at which the braking force of the dynamic brake by the switching element weakens), the power supply line is switched to a dynamic brake circuit that includes a resistor. is shorted through a resistor to slow down the motor and then stop it. This prevents the braking force from the dynamic brake from weakening in the latter half of an emergency stop, and generates a strong braking force during the entire period of an emergency stop, increasing the time it takes for the synchronous motor to stop. It is shortened.

Patent No. 3279102

However, when the synchronous motor is brought to an emergency stop, the braking force by the dynamic brake is prevented from weakening and the time until the synchronous motor stops is shortened, as in the case of the synchronous motor of Patent Document 1 mentioned above. It is thought that the braking force of the dynamic brake on the electric motor may become too strong. In particular, when the synchronous motor of Patent Document 1 is applied to the motor of a bipedal robot such as a humanoid robot, the braking force of the dynamic brake becomes too strong during an emergency stop, causing the robot to suddenly stop. do. As a result, there is a problem that the robot may fall down violently and be damaged. Furthermore, when the synchronous motor of Patent Document 1 is applied to the motor of a quadruped walking robot, the quadruped robot will not fall during an emergency stop (abnormal stop), but it may be damaged by the shock caused by the emergency stop. There is a problem.

This invention has been made to solve the above-mentioned problems, and one purpose of the invention is to provide a robot, a humanoid robot, and a robot that can control the collapse of the robot, which can prevent damage during abnormal stops. The purpose is to provide a method.

In order to achieve the above object, a robot according to a first aspect of the present invention includes a robot main body including a plurality of joints, a plurality of motors provided in each of the plurality of joints, and a three-phase motor in the windings of the motors. A drive circuit section that drives the motor by supplying AC power and operates a dynamic brake on the motor, and a drive circuit section that controls the drive circuit section and controls the braking force of the dynamic brake by the drive circuit section. The drive circuit control section includes a plurality of upper arm side switching elements constituting the upper arm and a plurality of lower arm side switching elements constituting the lower arm, and the drive circuit control section is configured to prevent abnormal stoppage. When stopping at least one of the plurality of motors, at least some of the plurality of upper arm side switching elements or at least some of the plurality of lower arm side switching elements are alternately turned on and off. The controller is configured to perform control to reduce the braking force of the dynamic brake until the motor stops so that the posture of the robot main body gradually changes . Further, abnormal stop is a broad concept that includes bringing the robot to an emergency stop due to a user's operation and stopping the robot abnormally due to an abnormality.

In the robot according to the first aspect of the present invention, as described above, when stopping at least one of the plurality of motors during an abnormal stop, the drive circuit control section controls at least one of the plurality of upper arm side switching elements. The control device is configured to perform control to reduce the braking force of the dynamic brake until the motor stops by alternately repeating an on state and an off state of at least a part of the lower arm side switching element or the plurality of lower arm side switching elements. . As a result, when stopping the motor during an abnormal stop, the braking force of the dynamic brake is reduced, so the robot stops relatively slowly. As a result, when the robot is a bipedal robot such as a humanoid robot, the robot is prevented from falling over violently. In other words, the robot falls down gradually. In addition, in the case of a quadruped walking robot, the impact caused by an abnormal stop can be alleviated. As a result, damage during abnormal stop can be suppressed. In addition, as described above, control is performed to reduce the braking force of the dynamic brake until the motor stops, so unlike the case where the braking force of the dynamic brake is increased again until the motor stops, the motor It is possible to prevent the robot from suddenly stopping and falling over violently until it stops (on the way).

Furthermore, if the braking force of the dynamic brake is too strong, the robot may fall over with its joints fixed by the strong braking force of the dynamic brake. This may also cause damage to the robot. In contrast, in the robot according to the first aspect of the present invention, as described above, control is performed to reduce the braking force of the dynamic brake by alternately repeating the on state and off state of the switching element that drives the motor. By configuring the motor to continue until it stops, the joints are prevented from being fixed by the strong braking force of the dynamic brake, which prevents damage to the robot caused by the robot falling over with the joints fixed. can be suppressed. In particular, when the present invention is applied to a humanoid robot, the joints (shoulder joint and knee joint) are prevented from being fixed by strong braking force when the arm is raised and the knee is extended. At the same time, the reduced braking force can gradually shift to a state where the arms are lowered and the knees are bent (squatting position), causing the patient to fall. Thereby, damage caused by falling can be effectively suppressed, especially in the humanoid robot.
A robot according to a second aspect of the invention includes a robot body including a plurality of joints, a plurality of motors provided in each of the plurality of joints, and a motor by supplying three-phase AC power to the windings of the motors. a drive circuit section that drives the motor and applies a dynamic brake to the motor; a drive circuit control section that controls the drive circuit section and controls the braking force of the dynamic brake by the drive circuit section; a detection unit for detecting at least one of the voltage and current of the power supply path that supplies the power, and the drive circuit unit includes a plurality of upper arm-side switching elements that configure the upper arm and a lower arm that configures the lower arm. and a plurality of lower arm side switching elements, and the drive circuit control section controls the voltage and current of the power supply path detected by the detection section when stopping at least one motor of the plurality of motors during an abnormal stop. The motor is stopped by alternately repeating the on state and the off state of at least some of the plurality of upper arm side switching elements or at least some of the plurality of lower arm side switching elements based on at least one of the above. The system is configured to perform feedback control to reduce the braking force of the dynamic brake until the brake force is reached.

A humanoid robot according to a third aspect of the invention includes a humanoid robot body including a plurality of joints corresponding to a plurality of joints of a human, a plurality of motors provided in each of the plurality of joints, and a winding of the motor. A drive circuit section that drives the motor by supplying three-phase AC power to the motor and operates a dynamic brake on the motor, and a drive circuit section that controls the drive circuit section and controls the braking force of the dynamic brake by the drive circuit section. The drive circuit controller includes a plurality of upper arm-side switching elements that configure the upper arm and a plurality of lower arm-side switching elements that configure the lower arm. When stopping at least one of the plurality of motors during an abnormal stop, the on state and off state of at least some of the plurality of upper arm side switching elements or at least some of the plurality of lower arm side switching elements are changed. By repeating this alternately, control is performed to reduce the braking force of the dynamic brake until the motor stops so that the posture of the humanoid robot body gradually changes .

In the humanoid robot according to the third aspect of the present invention, as described above, when stopping at least one of the plurality of motors during an abnormal stop, the drive circuit control section controls the plurality of upper arm side switching elements. The control device is configured to perform control to reduce the braking force of the dynamic brake until the motor stops by alternately repeating on and off states of at least a portion or a plurality of lower arm side switching elements. ing. As a result, when stopping the motor in the event of an abnormal stop, the braking force of the dynamic brake is reduced, so the humanoid robot stops relatively slowly. This prevents the humanoid robot from falling over violently. In other words, the humanoid robot falls down gradually. As a result, it is possible to suppress damage caused by the humanoid robot falling violently during an abnormal stop. In addition, as described above, control is performed to reduce the braking force of the dynamic brake until the motor stops, so unlike the case where the braking force of the dynamic brake is increased again until the motor stops, the motor It is possible to prevent the humanoid robot from suddenly stopping and falling over violently until it stops (on the way).

Furthermore, if the braking force of the dynamic brake is too strong, the humanoid robot may fall over with its joints fixed by the strong braking force of the dynamic brake. This may also cause damage to the humanoid robot. In contrast, in the humanoid robot according to the second aspect of the present invention, as described above, the braking force of the dynamic brake is transferred to the motor by alternately repeating the on state and the off state of the switching element that drives the motor. By configuring the control to decrease the amount until it stops, the joints are prevented from being fixed by the strong braking force of the dynamic brake, which prevents the humanoid robot from falling over with the joints fixed. damage to humanoid robots can be suppressed. In addition, it is possible to prevent the joints (shoulder joints and knee joints) from being fixed due to strong braking force when the arm of the humanoid robot is raised and the knee is extended. A weak braking force causes the robot to gradually shift to a state where its arms are lowered and its knees are bent (squatting position), causing it to fall. Thereby, damage caused by falling can be effectively suppressed, especially in the humanoid robot.

A fourth aspect of the present invention provides a method for controlling the fall of a robot including a plurality of joints, wherein the voltage of a power supply path that supplies power to a plurality of motors provided in each of the plurality of joints is provided. and detecting at least one of the detected voltage and current of the power supply path, and supplying three-phase AC power to the windings of the plurality of motors based on the detected at least one of the voltage and the current of the power supply path. At least a portion of the plurality of upper arm side switching elements or at least a portion of the lower arm side switching elements included in the drive circuit section that drives the motor and operates a dynamic brake on at least one of the plurality of motors. The method further includes a step of performing feedback control to reduce the braking force of the dynamic brake until the motor stops so that the posture of the robot gradually changes by alternately repeating the on state and the off state.

In the robot collapse control method according to the fourth aspect of the present invention, as described above, the three-phase alternating current is applied to the windings of the plurality of motors based on at least one of the detected voltage and current of the power supply path. At least a portion of the plurality of upper arm-side switching elements or the lower arm side included in a drive circuit section that drives the motor by supplying electric power and operates a dynamic brake for at least one of the plurality of motors. The method includes a step of performing feedback control to reduce the braking force of the dynamic brake until the motor stops by alternately repeating on and off states of at least a portion of the switching element. As a result, when stopping the motor during an abnormal stop, the braking force of the dynamic brake is reduced, so the robot stops relatively slowly. As a result, when the robot is a bipedal robot such as a humanoid robot, the robot is prevented from falling over violently. In other words, the robot falls down gradually. In addition, in the case of a quadruped walking robot, the impact caused by an abnormal stop can be alleviated. As a result, it is possible to provide a robot fall control method that can suppress damage caused by the robot falling violently during an abnormal stop. In addition, as described above, control is performed to reduce the braking force of the dynamic brake until the motor stops, so unlike the case where the braking force of the dynamic brake is increased again until the motor stops, the motor It is possible to provide a method for controlling the fall of a robot, which can prevent the robot from abruptly stopping and falling violently before it stops (on the way).

Furthermore, if the braking force of the dynamic brake is too strong, the robot may fall over with its joints fixed by the strong braking force of the dynamic brake. This may also cause damage to the robot. In contrast, in the robot according to the third aspect of the present invention, as described above, control is performed to reduce the braking force of the dynamic brake by alternately repeating the on state and the off state of the switching element that drives the motor. By configuring the motor to continue until it stops, the joints are prevented from being fixed by the strong braking force of the dynamic brake, which prevents damage to the robot caused by the robot falling over with the joints fixed. It is possible to provide a method for controlling a robot that can suppress the collapse of the robot. In particular, when the present invention is applied to a humanoid robot, the joints (shoulder joint and knee joint) are prevented from being fixed by strong braking force when the arm is raised and the knee is extended. At the same time, the reduced braking force can gradually shift to a state where the arms are lowered and the knees are bent (squatting position), causing the patient to fall. Thereby, it is possible to provide a robot fall control method that can effectively suppress damage caused by falling, especially in a humanoid robot.
A robot tilting control method according to a fifth aspect of the present invention is a robot tilting control method including a plurality of joints, which detects at least one of a voltage and a current of a power supply path that supplies power to a motor. detecting at least one of the voltage and current of the power supply path by the detection unit for detecting the windings of the plurality of motors based on the detected at least one of the voltage and current of the power supply path; At least a portion of the plurality of upper arm side switching elements included in a drive circuit section that drives the motor by supplying three-phase AC power and operates a dynamic brake on at least one of the plurality of motors. Alternatively, the method includes a step of performing feedback control to reduce the braking force of the dynamic brake until the motor stops by alternately repeating the ON state and OFF state of at least a portion of the lower arm side switching element.

According to the present invention, as described above, damage at the time of abnormal stop can be suppressed.

FIG. 1 is a perspective view of a humanoid robot according to an embodiment of the present invention. FIG. 1 is a block diagram of a humanoid robot (humanoid robot main body) according to an embodiment of the present invention. FIG. 2 is a circuit diagram of an amplifier for a humanoid robot according to an embodiment of the present invention. FIG. 2 is a flow diagram for explaining a method for controlling the fall of a humanoid robot according to an embodiment of the present invention. 1 is a diagram showing a humanoid robot in a crouching state according to an embodiment of the present invention; FIG. FIG. 2 is a diagram showing a state in which an arm of a humanoid robot according to an embodiment of the present invention is arranged along a horizontal direction.

EMBODIMENT OF THE INVENTION Hereinafter, one embodiment of the present invention that embodies the present invention will be described based on the drawings.

With reference to FIGS. 1 to 3, the configuration of a humanoid robot 100 (humanoid robot main body 100a) having a plurality of joints corresponding to a plurality of human joints according to the present embodiment will be described. Furthermore, the humanoid robot 100 is also called a humanoid. Note that the humanoid robot 100 and the humanoid robot main body 100a are examples of a "robot" and a "robot main body" in the claims, respectively.

As shown in FIG. 1, the humanoid robot 100 includes a head 1, a neck 2, an upper body 3, a lower body 4, arms 5, hands 6, legs 7, and feet 8. There is. The upper torso section 3 and the lower torso section 4 are bendably connected via a waist joint 10a. Thereby, the upper body part 3 can perform a forward bending motion, a backward bending motion, and a left and right turning motion with respect to the lower body part 4. The lower torso portion 4 corresponds to the human pelvis. Further, the waist joint 10a corresponds to the human waist.

Further, the arm portion 5 includes a plurality of links 20 and an elbow joint 10b that bendably supports the plurality of links 20. Then, the arm portion 5 performs a bending motion by mutually bending the adjacent links 20 via the elbow joints 10b.

The hand portion 6 is provided at the tip of the arm portion 5. The hand portion 6 has a plurality of links (not shown) and a finger joint (not shown) that bendably supports the plurality of links.

The leg portion 7 includes a plurality of links 20 and a knee joint 10c that bendably supports the plurality of links 20. Then, as the adjacent links 20 bend with respect to each other via the knee joint 10c, the leg portion 7 performs a bending motion. By controlling the bending motion of the legs 7 and moving the feet 8, the humanoid robot 100 can walk on two legs.

The upper body part 3 and the arm part 5 are connected by a shoulder joint 10d. Further, the lower body portion 4 and the leg portions 7 are connected by a hip joint 10e. The leg portion 7 and the foot portion 8 are connected by an ankle joint (ankle joint) 10f. Note that the hip joint 10a, elbow joint 10b, knee joint 10c, shoulder joint 10d, hip joint 10e, and ankle joint 10f are examples of "joints" in the claims.

The above-mentioned waist joint 10a, elbow joint 10b, knee joint 10c, shoulder joint 10d, hip joint 10e and ankle joint 10f include the waist joint 10a, elbow joint 10b, knee joint 10c, shoulder joint 10d, hip joint 10e and ankle joint, respectively. A motor 30 is provided to drive 10f. By driving the waist joint 10a, elbow joint 10b, knee joint 10c, shoulder joint 10d, hip joint 10e, and ankle joint 10f by the motor 30, the humanoid robot 100 performs a bending motion and a turning motion. Note that, in reality, joints and motors 30 are also provided in locations other than those shown in FIG. 1, but these are omitted for the sake of simplifying the explanation.

As shown in FIG. 2, the humanoid robot 100 (humanoid robot body 100a) is provided with a power source 40, a power relay board 50, and an amplifier unit 60 in addition to the motor 30 described above. Note that in FIG. 2, broken line arrows represent communication signals. Further, the thin solid line arrow represents the control power. Further, the thick solid line arrow represents the motor power that drives the motor 30.

A posture sensor 70 is provided in the humanoid robot 100 (humanoid robot main body 100a). The posture sensor 70 is configured to detect information regarding the posture of the humanoid robot 100 (whether it is standing, sitting, arms raised, arms lowered, etc.).

Motor drive power is supplied to the power supply relay board 50 from the power supply 40 . The power relay board 50 is configured to supply power for driving the motor 30 to the amplifier unit 60.

Control power is supplied to the power supply relay board 50 from the power supply 40 . The power relay board 50 is configured to supply power for controlling the amplifier unit 60.

The amplifier unit 60 includes a plurality of amplifiers (servo amplifiers) 61. The amplifier 61 is provided for each of the plurality of motors 30 provided at the waist joint 10a, elbow joint 10b, knee joint 10c, shoulder joint 10d, hip joint 10e, ankle joint 10f (see FIG. 1), etc. . Further, the amplifier 61 controls driving of the motor 30.

As shown in FIG. 3, the amplifier 61 includes an inverter section 61a and a control section 61b that controls the inverter section 61a. The inverter section 61a is configured to drive the motor 30 by supplying three-phase AC power to the windings of the motor 30, and to actuate a dynamic brake on the motor 30. Furthermore, the inverter section 61a includes a plurality of (in this embodiment, three) upper arm side switching elements SW1, SW2, and SW3 that constitute an upper arm, and a plurality (in this embodiment, three) of upper arm side switching elements that constitute a lower arm. The lower arm side switching elements SW4, SW5, and SW6 are included. The control unit 61b controls the inverter unit 61a and also controls the braking force of the dynamic brake by the inverter unit 61a. Specifically, the control unit 61b controls on/off of the switching elements (SW1 to SW6), thereby supplying desired three-phase (U, V, and W) power to the motor 30. Further, the control of the braking force of the dynamic brake by the control unit 61b will be described later. Note that the inverter section 61a is an example of a "drive circuit section" in the claims. Further, the control section 61b is an example of a "drive circuit control section" in the claims.

Each of the switching elements (SW1 to SW6) includes a bipolar transistor. Collectors C of the upper arm side switching elements SW1, SW2, and SW3 are connected to the positive side potential wiring 62. The emitters E of the lower arm side switching elements SW4, SW5, and SW6 are connected to the negative side potential wiring 63. Furthermore, the emitters E of the upper arm side switching elements SW1, SW2, and SW3 and the collectors C of the lower arm side switching elements SW4, SW5, and SW6 are connected to the motor 30 via the power supply wiring 64. Note that the power supply wiring 64 includes three wirings: U-phase, V-phase, and W-phase. Further, the power supply wiring 64 is an example of a "power supply path" in the claims.

Further, in this embodiment, a voltage detection unit 61c is provided for detecting at least one of the voltage and current (voltage in this embodiment) of the power supply wiring 64 that supplies power to the motor 30. Specifically, the voltage detection unit 61c detects the voltage of the power supply wiring 64 between the switching elements (SW1 to SW6) and the motor 30. Further, the motor 30 is provided with an encoder 65 that detects the rotational speed and rotational position of the motor 30. The rotational speed and rotational position of the motor 30 detected by the encoder 65 are input to the control section 61b. Note that the voltage detection section 61c is an example of a "detection section" in the claims.

(Normal regeneration operation)

Normally, electric power is regenerated when a command to decelerate or reverse is given to the motor 30 (see FIG. 2) of the humanoid robot 100. A regeneration resistor (not shown) is connected to prevent the voltage of the positive potential wiring 62 from becoming too large during power regeneration. For example, during normal regeneration operation, if the voltage of the positive potential wiring 62 exceeds 200 V, a regenerative resistor (not shown) is connected to suppress the increase in the voltage of the positive potential wiring 62. As a result, a part of the regenerated power is consumed as heat by the regeneration resistor, so that it is possible to suppress the voltage of the positive side potential wiring 62 from becoming too large. Furthermore, the portion of the regenerated power that is not consumed as heat by the regenerative resistor is stored in the power source 40.

(Dynamic brake weakening control during emergency stop)

An emergency stop of the humanoid robot 100 will be explained. The emergency stop is an operation in which the humanoid robot 100 is stopped by stopping the motor 30 by the user pressing the emergency stop button 80 (see FIG. 3). During an emergency stop, the operation of the amplifier 61 (see FIG. 2) is stopped, and the power supply from the power source 40 is stopped. Note that the emergency stop is an example of an "abnormal stop" in the claims.

In addition, at the time of emergency stop, at least a portion (in this embodiment, all three) of the three lower arm side switching elements SW4, SW5, and SW6 are turned on, so that the turned on lower arm side switching elements SW4, SW5, and SW6 are turned on. A closed path consisting of the SW 6, the power supply wiring 64, and the motor 30 is formed. Note that the upper arm side switching elements SW1, SW2, and SW3 are turned off. At this time, since an induced voltage is generated in each phase of the motor 30, a current flows in each phase. Then, a torque proportional to this current acts in a direction to decelerate the motor 30. That is, a dynamic brake acts on the motor 30. This applies braking force to the motor 30.

Here, in the present embodiment, when stopping the plurality of motors 30 during an emergency stop, the control unit 61b controls at least a portion of the plurality (three) upper arm side switching elements SW1, SW2, and SW3 or a plurality (three) of the upper arm side switching elements SW1, SW2, and SW3. By alternately repeating the ON and OFF states of at least some of the lower arm side switching elements SW4, SW5, and SW6, control is performed to reduce the braking force of the dynamic brake until the motor 30 stops. It is composed of Specifically, when stopping the plurality of motors 30 during an emergency stop, the control unit 61b alternately switches all of the plurality (three) lower arm side switching elements SW4, SW5, and SW6 between the on state and the off state. have them repeat. As a result, the humanoid robot 100 gradually changes its posture. Furthermore, until the operation of the humanoid robot 100, which has a waist joint 10a, an elbow joint 10b, a knee joint 10c, a shoulder joint 10d, a hip joint 10e, and an ankle joint 10f corresponding to multiple human joints, is completely stopped. , the braking force of the dynamic brake is reduced.

Furthermore, in the present embodiment, when controlling the fall of the humanoid robot main body 100a during an emergency stop, the control unit 61b turns on all three upper arm side switching elements SW1, SW2, and SW3, and The braking force of the dynamic brake is controlled to be reduced until the motor 30 stops by alternately repeating the on state and off state of all three lower arm side switching elements SW4, SW5 and SW6. ing. The humanoid robot body 100a includes a machine for fixing (maintaining posture) the waist joint 10a, elbow joint 10b, knee joint 10c, shoulder joint 10d, hip joint 10e, and ankle joint 10f of the humanoid robot body 100a. There is no standard brake (electromagnetic brake) installed. Therefore, at the time of emergency stop, the humanoid robot main body 100a eventually collapses. In this embodiment, by operating a dynamic brake whose braking force is reduced by turning on and off the three lower arm side switching elements SW4, SW5, and SW6, the humanoid robot main body 100a falls down relatively gently. control so that

Further, in this embodiment, the amplifier 61 (inverter section 61a) is provided for each of a plurality of joints (lumbar joint 10a, elbow joint 10b, knee joint 10c, shoulder joint 10d, hip joint 10e, and ankle joint 10f). are individually provided for each motor 30. Then, when stopping the motor 30 during an emergency stop, the control section 61b controls the on state and off state of all the lower arm side switching elements SW4, SW5, and SW6 of the inverter section 61a provided for each motor 30. By repeating the process alternately, the braking force of the dynamic brake for the plurality of motors 30 is individually controlled. That is, for each inverter section 61a provided for each motor 30, the three lower arm side switching elements ON/OFF of SW4, SW5 and SW6 is controlled. For example, at a certain point in time, the number of rotations of the motor 30 (the induced voltage generated by the rotation of the motor 30) of each of the plurality of joints may be different. In this case, there may be a mixture of joints where the dynamic brake operates and joints where the dynamic brake does not operate. Note that the inverter section 61a is an example of a "drive circuit section" in the claims.

In the present embodiment, when stopping the motor 30 during an emergency stop, the control unit 61b sets all of the lower arm side switching elements SW4, SW5, and SW6 of the inverter unit 61a provided for each motor 30 to the ON state. By alternately repeating the dynamic brake and the off state, some of the plurality of joints are configured to be controlled to reduce the braking force of the dynamic brake more than other joints. Specifically, the joints whose braking force is reduced include at least one of the knee joint 10c and the shoulder joint 10d (in this embodiment, both). In this embodiment, as will be described later, control is performed to reduce the braking force of the dynamic brake not only for the knee joint 10c but also for the hip joint 10e and the ankle joint 10f. Further, the braking force of the dynamic brake can be adjusted by changing a predetermined threshold value with which the voltage of the power supply wiring 64 detected by the voltage detection unit 61c is compared.

Furthermore, in this embodiment, the braking force of the dynamic brake of at least one (in this embodiment, both) of the knee joint 10c or the shoulder joint 10d is determined based on the position information of the knee joint 10c and the position information of the shoulder joint 10d. The structure is configured to perform control to reduce the Specifically, information regarding the posture of the humanoid robot 100 (whether it is standing, sitting, arms raised, arms lowered, etc.) from the posture sensor 70 provided in the humanoid robot main body 100a is collected. ), the position information of the knee joint 10c (whether the knee is extended or bent, etc.) and the position information of the shoulder joint 10d (the arm part 5 is raised around the shoulder joint 10d, ) is obtained. Then, based on the acquired position information of the knee joint 10c and the acquired position information of the shoulder joint 10d, control is performed to reduce the braking force of the dynamic brake of the knee joint 10c and the shoulder joint 10d. For example, if it is determined that the humanoid robot 100 is standing (knees are extended) based on information regarding the posture of the humanoid robot 100 from the posture sensor 70, the humanoid robot 100 is caused to fall down gently. Thus, control is performed to reduce the braking force of the dynamic brakes of the knee joint 10c, hip joint 10e, and ankle joint 10f. Furthermore, if it is determined that the arm portion 5 of the humanoid robot 100 is raised around the shoulder joint 10d based on the information regarding the posture of the humanoid robot 100 from the posture sensor 70, the arm portion of the humanoid robot 100 Control is performed to reduce the braking force of the dynamic brake of the shoulder joint 10d so that the shoulder joint 5 is lowered gently.

Further, in this embodiment, the voltage of the power supply wiring 64 that supplies power to the motor 30 is detected by the voltage detection unit 61c. Then, when stopping the motor 30, the control unit 61b sets all of the three lower arm side switching elements SW4, SW5, and SW6 to the ON state based on the voltage of the power supply wiring 64 detected by the voltage detection unit 61c. By alternately repeating the OFF state and the OFF state, feedback control is performed to reduce the braking force of the dynamic brake until the motor 30 stops. Specifically, when stopping the motor 30 during an emergency stop, the control unit 61b compares the voltage of the power supply wiring 64 detected by the voltage detection unit 61c with a predetermined threshold value. Then, based on the comparison between the voltage of the power supply wiring 64 and a predetermined threshold value, the three lower arm side switching elements SW4, SW5, and SW6 are alternately turned on and off. As a result, feedback control is performed to reduce the braking force of the dynamic brake until the motor 30 stops. Note that the predetermined threshold value is set so that the voltage of the power supply wiring 64 becomes a relatively low voltage (for example, 30 V or more and 60 V or less) during an emergency stop. That is, the predetermined threshold value is lower than the reference voltage to which the regenerative resistor is connected during normal operation.

Specifically, in the present embodiment, the control unit 61b detects a voltage drop when the voltage of the power supply wiring 64 detected by the voltage detection unit 61c exceeds a predetermined threshold when stopping the motor 30 during an emergency stop. All of the arm-side switching elements SW4, SW5, and SW6 are turned on. Furthermore, when the voltage of the power supply wiring 64 is below a predetermined threshold, the control unit 61b turns off all of the lower arm side switching elements SW4, SW5, and SW6. Thereby, the control unit 61b is configured to perform feedback control to reduce the braking force of the dynamic brake until the motor 30 stops.

(Collapse control method)
Next, a method for controlling the humanoid robot 100 to fall during an emergency stop will be described with reference to FIGS. 1 and 4.

In step S1 shown in FIG. 4, the emergency stop button 80 is pressed. As a result, an emergency stop signal is input to the control section 61b of the amplifier 61.

In step S2, the voltage of the power supply wiring 64 that supplies power to the plurality of motors 30 provided in each of the hip joint 10a, elbow joint 10b, knee joint 10c, shoulder joint 10d, hip joint 10e, and ankle joint 10f is determined by the voltage detection unit. 61c.

In step S3, the control section 61b compares the voltage of the power supply wiring 64 detected by the voltage detection section 61c with a predetermined threshold value.

In this embodiment, based on the detected voltage of the power supply wiring 64, the lower arm side switching elements SW4, SW5, and SW6 included in the inverter section 61a are alternately turned on and off. , feedback control is performed to reduce the braking force of the dynamic brake until the motor 30 stops. Note that, at this time, the upper arm side switching elements SW1, SW2, and SW3 are all in the off state. Specifically, in step S3, if the voltage of the power supply wiring 64 detected by the voltage detection unit 61c is higher than a predetermined threshold, the process proceeds to step S4, and all of the lower arm side switching elements SW4, SW5, and SW6 are is turned on. This activates the dynamic brake. Further, in step S3, if the voltage of the power supply wiring 64 detected by the voltage detection unit 61c is equal to or lower than a predetermined threshold value, the process proceeds to step S5, and all of the lower arm side switching elements SW4, SW5, and SW6 are turned off. . As a result, the operation of the dynamic brake is stopped.

Note that the operations from step S3 to step S5 are continued until the motor 30 stops. As a result, feedback control is performed to reduce the braking force of the dynamic brake until the motor 30 stops.

Next, an operation in which the humanoid robot 100 collapses during an emergency stop will be specifically described.

For example, as shown in FIG. 1, when it is determined that the humanoid robot 100 is standing based on information regarding the posture of the humanoid robot 100 from the posture sensor 70 at a time before the emergency stop (for example, , the built-in PC 40), control is performed to reduce the braking force of the dynamic brakes of the knee joint 10c, hip joint 10e, and ankle joint 10f so as to cause the humanoid robot 100 to fall down gently. It is assumed that control to reduce the braking force of the dynamic brake is not performed on joints other than the knee joint 10c, hip joint 10e, and ankle joint 10f.

When the emergency stop button 80 (see FIG. 3) is pressed, the supply of power to the motor 30 is stopped. In addition, in the humanoid robot 100, a mechanical Since no electromagnetic brake is provided, the humanoid robot 100 cannot maintain its posture due to the power supply to the motor 30 being stopped. Therefore, the humanoid robot 100 falls down from an upright state so that the knee joints 10c and hip joints 10e of the legs 7 and the ankle joints 10f of the feet 8 are bent, as shown in FIG.

When bending the knee joint 10c, the hip joint 10e, and the ankle joint 10f, the motor 30 operates to generate electricity because the power supply to the motor 30 is stopped. Then, when bending the knee joint 10c, hip joint 10e, and ankle joint 10f, the rotational speed of the motor 30 gradually increases, and the generated electric power (voltage) also increases. Further, the generated power is supplied to the power supply wiring 64. As a result, the voltage of the power supply wiring 64 also increases. Then, the voltage of the power supply wiring 64 is detected by the voltage detection section 61c.

Then, based on the detected voltage of the power supply wiring 64, all of the lower arm side switching elements SW4, SW5, and SW6 are alternately turned on and off, thereby creating a dynamic state until the motor 30 stops. Feedback control is performed to reduce the braking force of the brake. Note that since the predetermined threshold value is set relatively low, the dynamic brake for the motor 30 starts to act when the rotational speed of the motor 30 is relatively low, and the braking force of the dynamic brake is relatively weak. As a result, the posture of the humanoid robot 100 is shifted so that the knee joint 10c, the hip joint 10e, and the ankle joint 10f are gently bent, and then the humanoid robot 100 stops operating. After that, the humanoid robot 100 collapses (falls over). In this way, the humanoid robot 100 is stopped relatively slowly, so that the humanoid robot 100 is prevented from falling over violently.

Further, as shown in FIG. 6, at a time before the emergency stop, the arm portion 5 of the humanoid robot 100 is moved around the shoulder joint 10d based on the information regarding the posture of the humanoid robot 100 from the posture sensor 70. If it is determined that the arm 5 of the humanoid robot 100 is lowered gently, control is performed to reduce the braking force of the dynamic brake of the shoulder joint 10d. Note that when the emergency stop button 80 is pressed in the state of the humanoid robot 100 in FIG. 6, the knee joint 10c, hip joint 10e, and ankle joint 10f are also bent as described above. A case will be described in which only the posture of the arm portion 5 changes without the knee joint 10c, hip joint 10e, and ankle joint 10f being bent.

In this state, when the emergency stop button 80 is pressed, the supply of power to the amplifier 61 and the motor 30 is stopped. Since the humanoid robot 100 is not provided with a brake for fixing the shoulder joint 10d, the shoulder joint 10d rotates due to the weight of the arm 5. As a result, the arm portion 5, which has been arranged along the horizontal direction, rotates in an arc around the shoulder joint 10d. At this time, since the supply of electric power to the motor 30 is stopped, the motor 30 operates to generate electricity. Then, while the shoulder joint 10d is rotating, the voltage of the power supply wiring 64 is compared with a predetermined threshold value, and all of the lower arm side switching elements SW4, SW5, and SW6 are alternately turned on and off. repeated. As a result, the braking force of the dynamic brake is weakened, so the arm portion 5 rotates relatively gently around the shoulder joint 10d and then stops. In this way, the arm portion 5 stops relatively slowly, so that the arm portion 5 is prevented from colliding forcefully with the upper body portion 3 or the lower body portion 4, etc.

Furthermore, when the emergency stop button 80 is pressed while the humanoid robot 100 is in motion (when the rotational speed of the motor 30 is relatively high), based on the information regarding the posture of the humanoid robot 100 from the posture sensor 70, Then, it is determined which joint of the humanoid robot 100 the braking force of the dynamic brake is to be reduced. When the rotation speed of the motor 30 is relatively high, the voltage of the electric power generated by the motor 30 is relatively high, so that dynamic braking is applied. As a result, the lower arm of the inverter section 61a corresponding to the motor 30 reduces the braking force of the dynamic brake while the rotational speed of the motor 30 decreases and the voltage of the generated power decreases to near a predetermined threshold value. All of the side switching elements SW4, SW5, and SW6 are alternately turned on and off. This weakens the braking force of the dynamic brake. As a result, the humanoid robot 100 is prevented from falling over in a state where the joints of the humanoid robot 100 are fixed (rigid state).

[Effects of this embodiment]
In this embodiment, the following effects can be obtained.

In this embodiment, as described above, when stopping the plurality of motors 30 during an emergency stop, the control unit 61b controls at least a portion of the plurality of upper arm side switching elements SW1, SW2, and SW3 or a plurality of lower arm side switching elements SW1, SW2, and SW3. The motor 30 is stopped by alternately repeating the on state and the off state of at least some of the switching elements SW4, SW5, and SW6 (in this embodiment, all of the lower arm side switching elements SW4, SW5, and SW6). The system is configured to perform control to reduce the braking force of the dynamic brake up to the maximum. As a result, when stopping the motor 30 during an emergency stop, the braking force of the dynamic brake is reduced, so the humanoid robot 100 stops relatively slowly. This prevents the humanoid robot 100 from falling over violently. In other words, the humanoid robot 100 falls down gently. As a result, damage caused by the humanoid robot 100 falling down violently during an emergency stop can be suppressed. Further, as described above, since the control is performed to reduce the braking force of the dynamic brake until the motor 30 stops, unlike the case where the braking force of the dynamic brake is increased again until the motor 30 stops, It is possible to prevent the humanoid robot 100 from abruptly stopping until the motor 30 stops (on the way) and causing the humanoid robot 100 to fall down violently.

Further, if the braking force of the dynamic brake is too strong, the humanoid robot 100 may fall over with the joints of the humanoid robot 100 being fixed by the strong braking force of the dynamic brake. This may also cause damage to the humanoid robot 100. In contrast, in the humanoid robot 100 of the present embodiment, as described above, the switching elements (lower arm side switching elements SW4, SW5, and SW6) that drive the motor 30 alternately repeat the on state and the off state. By controlling the braking force of the dynamic brake to be reduced until the motor 30 stops, the joint is prevented from being fixed by the strong braking force of the dynamic brake, so that the joint is fixed. Damage to the humanoid robot 100 caused by the humanoid robot 100 falling under such conditions can be suppressed. In particular, when the present invention is applied to the humanoid robot 100, the joints (shoulder joint 10d and knee joint 10c) are affected by strong braking force when the arm 5 (arm) is raised and the knee is extended. It is possible to prevent the person from being fixed, and the reduced braking force allows the person to gradually shift to a state where the arm portion 5 is lowered and a state where the knees are bent (squatting posture), thereby causing the person to fall over. Thereby, damage caused by falling can be effectively suppressed, especially in the humanoid robot 100.

Further, in this embodiment, as described above, when controlling the fall of the humanoid robot main body 100a during an emergency stop, the control unit 61b controls at least a portion of the plurality of upper arm side switching elements SW1, SW2, and SW3. Alternatively, by alternately repeating the on state and the off state of at least a portion of the plurality of lower arm side switching elements SW4, SW5, and SW6 (in this embodiment, all of the lower arm side switching elements SW4, SW5, and SW6). , is configured to perform control to reduce the braking force of the dynamic brake until the motor 30 stops. As a result, when controlling the humanoid robot main body 100a to fall down, the braking force of the dynamic brake is reduced during the period of the falling motion, so the humanoid robot main body 100a is controlled to fall down relatively gently. be able to.

In addition, in this embodiment, as described above, the inverter section 61a is configured to operate a plurality of motors provided for each of the plurality of waist joints 10a, elbow joints 10b, knee joints 10c, shoulder joints 10d, hip joints 10e, and ankle joints 10f. When stopping the motor 30 during an emergency stop, the control section 61b controls the plurality of upper arm side switching elements SW1, SW2, and SW3 of the inverter section 61a provided for each motor 30. or at least a portion of a plurality of lower arm side switching elements SW4, SW5, and SW6 (in this embodiment, all lower arm side switching elements SW4, SW5, and SW6) are alternately turned on and off. By repeating this, the braking force of the dynamic brake for the plurality of motors 30 is individually controlled. As a result, the joints (motors 30) to which the braking force of the dynamic brake should be weakened can be selected and individually controlled according to the posture of the humanoid robot 100 immediately before an emergency stop. The robot 100 can be moved to a crouched state more appropriately.

Furthermore, in the present embodiment, as described above, when stopping the motor 30 during an emergency stop, the control section 61b controls the plurality of upper arm side switching elements SW1 and SW2 of the inverter section 61a provided for each motor 30. and an on state and an off state of at least a part of SW3 or at least a part of a plurality of lower arm side switching elements SW4, SW5 and SW6 (in this embodiment, all of the lower arm side switching elements SW4, SW5 and SW6). By repeating the process alternately, some of the plurality of joints are controlled to reduce the braking force of the dynamic brake more than other joints. Here, depending on the posture of the humanoid robot 100 immediately before the emergency stop, control may not be performed to reduce the braking force of the dynamic brake for all joints (the braking force of the dynamic brake may only be reduced for some joints). ), it may be possible to suppress damage to the humanoid robot 100 due to falling. Therefore, as described above, by controlling some of the joints to reduce the braking force of the dynamic brake more than other joints, the braking force of the dynamic brake is reduced for all the joints. Compared to the case where control is performed, the control load on the humanoid robot 100 can be reduced.

Furthermore, in this embodiment, as described above, the joints to which the braking force is reduced include at least one of the knee joint 10c and the shoulder joint 10d. At the time of an emergency stop, if the braking force of the dynamic brake on the knee joint 10c is too strong, the knee joint 10c will be fixed by the strong braking force of the dynamic brake, so that the knee of the humanoid robot 100 will be in a humanoid state with its knees extended. The robot 100 falls. That is, since the humanoid robot 100 cannot be caused to fall down by gradually shifting to a state where the knees are bent (squatting position), the humanoid robot 100 may be damaged due to the fall. Therefore, as described above, by reducing the braking force of the dynamic brake on the knee joint 10c, the humanoid robot 100 can be caused to gradually shift to a bent state (crouching posture) and fall down. , damage to the humanoid robot 100 due to falling can be suppressed. Furthermore, during an emergency stop, if the braking force of the dynamic brake on the shoulder joint 10d is too strong, the shoulder joint 10d will be fixed by the strong braking force of the dynamic brake. The humanoid robot 100 falls down with the part 5 raised horizontally. In other words, it becomes impossible to cause the humanoid robot 100 to gradually shift from a horizontally raised state to a lowered state with the arm 5 centered around the shoulder joint 10d, causing the humanoid robot 100 to fall. may be damaged. Therefore, as described above, by reducing the braking force of the dynamic brake on the shoulder joint 10d, the state in which the arm 5 is raised horizontally around the shoulder joint 10d is gradually shifted from the state in which the arm 5 is lowered. Since the humanoid robot 100 can be caused to fall over, damage to the humanoid robot 100 due to the fall can be suppressed.

Further, in this embodiment, as described above, the braking force of the dynamic brake of at least one of the knee joint 10c and the shoulder joint 10d is reduced based on the position information of the knee joint 10c and the position information of the shoulder joint 10d. configured to perform control. Here, if the knee joint 10c of the humanoid robot 100 is in a pre-bent state (crouching position) or the arm part 5 is in a lowered state in the state immediately before the emergency stop, the reduction will be reduced. There is no need to gradually transition to a state where the knees are bent (squatting position) and the arm portions 5 are lowered due to a weak braking force. Therefore, as described above, by performing control to reduce the braking force of the dynamic brake of at least one of the knee joint 10c and the shoulder joint 10d, based on the position information of the knee joint 10c and the position information of the shoulder joint 10d. , it is possible to suppress control to reduce the braking force of the dynamic brake from being performed even when there is no need to reduce the braking force of the dynamic brake. Thereby, the control load on the humanoid robot 100 can be reduced.

In addition, in this embodiment, as described above, the humanoid robot body 100a includes a plurality of hip joints 10a, an elbow joint 10b, a knee joint 10c, a shoulder joint 10d, a hip joint 10e, and a foot joint, which correspond to a plurality of human joints. It has a joint 10f. Here, since the humanoid robot main body 100a walks on two legs, it is relatively easy to fall over. Therefore, as described above, during an emergency stop, the switching elements that drive the motor 30 (in this embodiment, the lower arm side switching elements SW4, SW5, and SW6) are alternately turned on and off, thereby creating a dynamic Performing control to reduce the braking force of the brake is particularly effective in suppressing damage to the humanoid robot 100, which is relatively prone to falling.

Further, in this embodiment, as described above, the voltage detection unit 61c is provided to detect at least one of the voltage and current (voltage in this embodiment) of the power supply wiring 64 that supplies power to the motor 30. Furthermore, when stopping the motor 30, the control unit 61b detects a plurality of At least some of the upper arm side switching elements SW1, SW2, and SW3 or at least some of the lower arm side switching elements SW4, SW5, and SW6 (in this embodiment, all of the lower arm side switching elements SW4, SW5, and SW6) ) is alternately turned on and off, thereby performing feedback control to reduce the braking force of the dynamic brake until the motor 30 stops. Here, as the rotation speed of the motor 30 increases, the electric power (voltage and current of the power supply wiring 64) generated by the motor 30 increases. Therefore, as described above, based on at least one of the voltage and current of the power supply wiring 64 detected by the voltage detection section 61c, at least a portion or a plurality of the upper arm side switching elements SW1, SW2, and SW3 are By alternately repeating the ON state and OFF state of at least some of the lower arm side switching elements SW4, SW5, and SW6, the rotation speed (voltage and voltage) of the motor 30 is suppressed from increasing excessively. I can do it. Thereby, it is possible to suppress the braking force of the dynamic brake applied to the motor 30 from becoming excessively strong.

Further, in the present embodiment, as described above, when stopping the motor 30 during an emergency stop, the control unit 61b uses at least one of the voltage and current of the power supply wiring 64 detected by the voltage detection unit 61c. , based on the comparison with a predetermined threshold value, at least a portion of the plurality of upper arm side switching elements SW1, SW2, and SW3 or at least a portion of the plurality of lower arm side switching elements SW4, SW5, and SW6 (in this embodiment, By alternately repeating the on state and off state of all of the lower arm side switching elements SW4, SW5, and SW6, feedback control is performed to reduce the braking force of the dynamic brake until the motor 30 stops. ing. As a result, the voltage (current) of the electric power generated by the motor 30 is suppressed from rising more than the voltage (current) according to the predetermined threshold value, and the voltage (current) close to the voltage (current) according to the predetermined threshold value is suppressed. (current), the braking force of the dynamic brake applied to the motor 30 can be maintained at a desired weak level.

Further, in the present embodiment, as described above, when stopping the motor 30 during an emergency stop, the control unit 61b controls at least one of the voltage and current of the power supply wiring 64 detected by the voltage detection unit 61c ( In this embodiment, when the voltage) exceeds a predetermined threshold, at least a portion of the plurality of upper arm side switching elements SW1, SW2, and SW3 or at least a portion of the plurality of lower arm side switching elements SW4, SW5, and SW6 (In this embodiment, all of the lower arm side switching elements SW4, SW5, and SW6) are turned on, and when at least one of the voltage and current of the power supply wiring 64 is equal to or lower than a predetermined threshold, the plurality of upper arm At least some of the side switching elements SW1, SW2, and SW3 or at least some of the lower arm side switching elements SW4, SW5, and SW6 (in this embodiment, all of the lower arm side switching elements SW4, SW5, and SW6) are turned off. In this state, feedback control is performed to reduce the braking force of the dynamic brake until the motor 30 stops. Thereby, when at least one of the voltage and current of the power supply wiring 64 detected by the voltage detection unit 61c exceeds a predetermined threshold, at least a portion of the plurality of upper arm side switching elements SW1, SW2, and SW3 or Since at least some of the lower arm side switching elements SW4, SW5, and SW6 are turned on, the voltage (current) of the power supply wiring 64 can be reduced. Further, when at least one of the voltage and current of the power supply wiring 64 detected by the voltage detection unit 61c is equal to or lower than a predetermined threshold, at least a portion or a plurality of the upper arm side switching elements SW1, SW2, and SW3 Since at least a portion of the lower arm side switching elements SW4, SW5, and SW6 are turned off, the voltage (current) of the power supply wiring 64 can be increased. Thereby, the voltage (current) of the electric power generated by the motor 30 can be easily maintained at a voltage (current) close to the voltage (current) corresponding to the predetermined threshold value.

Further, in this embodiment, as described above, based on at least one of the detected voltage and current (in this embodiment, voltage) of the power supply wiring 64, the windings of the plurality of motors 30 are connected to three phases. At least a part of the plurality of upper arm side switching elements SW1, SW2, and SW3 included in the inverter section 61a that drives the motor 30 by supplying AC power to the motor 30 and operates a dynamic brake on the motor 30, or the lower arm. The motor 30 is stopped by alternately repeating the on state and off state of at least some of the side switching elements SW4, SW5, and SW6 (in this embodiment, all of the lower arm side switching elements SW4, SW5, and SW6). The method further includes a step of performing feedback control to reduce the braking force of the dynamic brake until the braking force of the dynamic brake is reduced. As a result, when stopping the motor 30 during an emergency stop, the braking force of the dynamic brake is reduced, so the humanoid robot 100 stops relatively slowly. This prevents the humanoid robot 100 from falling over violently. In other words, the humanoid robot 100 falls down gently. As a result, it is possible to provide a method for controlling the fall of the humanoid robot 100 that can suppress damage caused by the humanoid robot 100 falling violently during an emergency stop. Further, as described above, since the control is performed to reduce the braking force of the dynamic brake until the motor 30 stops, unlike the case where the braking force of the dynamic brake is increased again until the motor 30 stops, A method for controlling the fall of a humanoid robot 100 that can prevent the humanoid robot 100 from abruptly stopping and falling violently until the motor 30 stops (on the way). can be provided.

Furthermore, as described above, the dynamic brake is controlled by alternately repeating the on state and the off state of the switching elements that drive the motor 30 (in this embodiment, all of the lower arm side switching elements SW4, SW5, and SW6). By configuring the control to reduce the power until the motor 30 stops, the joints are prevented from being fixed by the strong braking force of the dynamic brake, so the humanoid robot 100 can be moved with the joints fixed. It is possible to provide a method for controlling the fall of the humanoid robot 100 that can suppress damage to the humanoid robot 100 caused by the robot falling over. In addition, it is possible to prevent the joints (shoulder joint 10d and knee joint 10c) from being fixed by strong braking force when the arm portion 5 (arm) is raised and the knee is extended, and the braking force is also reduced. With a weak braking force, the arms 5 can be gradually shifted to a lowered state and the knees are bent (crouching position), and the robot can be caused to fall, thereby effectively suppressing damage caused by the fall. A method for controlling the fall of the humanoid robot 100 can be provided.

[Modified example]

Note that the embodiments disclosed this time should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is indicated by the claims rather than the description of the embodiments described above, and further includes all changes (modifications) within the meaning and range equivalent to the claims.

For example, in the above embodiment, an example was shown in which the present invention is applied to the humanoid robot 100, but the present invention is not limited to this. For example, the present invention may be applied to a bipedal robot or a quadrupedal robot imitating an animal other than the humanoid robot 100. When applied to a quadruped walking robot, it is possible to reduce the impact caused by an abnormal stop, so damage caused by an abnormal stop can be suppressed.

Further, in the above embodiment, an example was shown in which all of the lower arm side switching elements SW4, SW5, and SW6 are turned on and off during an emergency stop, but the present invention is not limited to this. For example, two of the lower arm side switching elements SW4, SW5, and SW6 may be turned on and off during an emergency stop. Furthermore, all of the upper arm side switching elements SW1, SW2, and SW3 (or two of the upper arm side switching elements SW1, SW2, and SW3) may be turned on and off during an emergency stop. In this case, the lower arm side switching elements SW4, SW5, and SW6 are turned off during the emergency stop. Note that even if the power supply to the amplifier 61 is stopped during an emergency stop, for example, as shown in FIG. A closed circuit is formed by a path via the positive potential wiring 62 and a path via the negative potential wiring 63, the free wheel diode of the lower arm side switching element SW5, the V-phase power supply wiring 64, and the motor 30. is possible. This makes it possible to apply braking force to the motor 30.

Further, in the above embodiment, an example is shown in which the control unit 61b compares the voltage of the power supply wiring 64 detected by the voltage detection unit 61c with a predetermined threshold value when stopping the motor 30 during an emergency stop. However, the present invention is not limited to this. For example, when stopping the motor 30 during an emergency stop, the control unit may compare the current in the power supply wiring 64 detected by the detection unit that detects the current with a predetermined threshold (current threshold). . Further, the control unit may compare the voltage and current of the power supply wiring 64 with respective threshold values.

Further, in the above embodiment, an example was shown in which the predetermined threshold value for turning on and off the lower arm side switching elements SW4, SW5, and SW6 during an emergency stop is lower than the reference voltage to which the regenerative resistor is connected during normal operation. The present invention is not limited to this. For example, if the reference voltage to which the regenerative resistor is connected during normal operation is relatively low, the predetermined threshold may be equivalent to the reference voltage to which the regenerative resistor is connected.

Further, in the above embodiment, an example was shown in which the humanoid robot 100 is brought to an emergency stop by pressing the emergency stop button 80 by the user, but the present invention is not limited to this. For example, the humanoid robot 100 may be provided with a sensor, and the humanoid robot 100 may be automatically brought to an emergency stop based on the sensor detecting the posture and motion of the humanoid robot 100. Further, when an abnormality occurs in the humanoid robot 100, control may be performed to reduce the braking force of the dynamic brake until the motor 30 stops.

Further, in the above embodiment, when stopping the motor 30 during an emergency stop, the lower arm side switching elements SW4, SW5, and SW6 are alternately turned on and off based on the voltage of the power supply wiring 64. However, the present invention is not limited thereto. For example, the rotation speed of the motor 30 is detected, and based on the detected rotation speed of the motor 30, the lower arm side switching elements SW4, SW5, and SW6 (or the upper arm side switching elements SW1, SW2, and SW3) are turned on. The state and the off state may be alternately repeated.

Further, in the above embodiment, an example was shown in which the braking force of the dynamic brake for the plurality of motors 30 is individually controlled, but the present invention is not limited to this. For example, the braking force of the dynamic brake for a plurality of motors 30 may be controlled all at once. That is, a voltage detection section 61c that detects the voltage of the power supply wiring 64 is provided in common for a plurality of amplifiers 61, and all the amplifiers 61 are connected based on the voltage detected by the commonly provided voltage detection section 61c. The on/off of the lower arm side switching elements SW4, SW5 and SW6 (or the upper arm side switching elements SW1, SW2 and SW3) may be controlled.

Further, in the above embodiment, an example is shown in which the braking force of the dynamic brake of the knee joint 10c (hip joint 10e, ankle joint 10f) and shoulder joint 10d is reduced, but the present invention is not limited to this. For example, the braking force of the dynamic brakes of all joints may be reduced (compared to during regeneration). Further, the braking force of the dynamic brake of joints other than the knee joint 10c (hip joint 10e, ankle joint 10f) and shoulder joint 10d may be reduced.

Further, in the above embodiment, information regarding the posture of the humanoid robot 100 (whether the humanoid robot 100 is standing, sitting, arms up, arms down, etc. , etc.) have been shown, but the present invention is not limited to this. For example, information regarding the posture of the humanoid robot 100 may be acquired by the encoder 65 provided on the motor 30. That is, information regarding the posture of the humanoid robot 100 is obtained based on the difference between the rotational position of the motor 30 in the posture of the humanoid robot 100 as a reference and the rotational position of the motor 30 in the posture of the humanoid robot 100 at the time of emergency stop. may be acquired, and a joint to which the braking force of the dynamic brake is to be reduced may be selected based on the acquired posture. Further, information regarding the posture of the humanoid robot 100 may be acquired using both the posture sensor 70 and the encoder 65.

Further, in the above embodiment, an example was shown in which the plurality of motors 30 provided in the humanoid robot 100 are controlled to reduce the braking force of the dynamic brake, but the present invention is not limited to this. For example, only one motor 30 of the plurality of motors 30 provided in the humanoid robot 100 may be controlled to reduce the braking force of the dynamic brake.

10a Hip joint (joint)
10b Elbow joint (joint)
10c Knee joint (joint)
10d Shoulder joint (joint)
10e Hip joint (joint)
10f Ankle joint (joint)
30 motor 60 amplifier unit 61a inverter section (drive circuit section)
61b control section (drive circuit control section)
61c Voltage detection section (detection section)
64 Power supply wiring (power supply route)
70 Posture sensor 100 Humanoid robot (robot)
100a Humanoid robot main body (robot main body)
SW1, SW2, SW3 Upper arm side switching element SW4, SW5, SW6 Lower arm side switching element

Claims (13)

A robot body including multiple joints,
a plurality of motors provided in each of the plurality of joints;
a drive circuit unit that drives the motor by supplying three-phase AC power to windings of the motor and operates a dynamic brake on the motor;
a drive circuit control section for controlling the drive circuit section and controlling the braking force of the dynamic brake by the drive circuit section;
The drive circuit section includes a plurality of upper arm side switching elements forming an upper arm and a plurality of lower arm side switching elements forming a lower arm,
When stopping at least one of the plurality of motors during an abnormal stop, the drive circuit control section controls at least a portion of the plurality of upper arm side switching elements or at least one of the plurality of lower arm side switching elements. Control is performed to reduce the braking force of the dynamic brake until the motor stops so that the posture of the robot main body gradually changes by alternately repeating an on state and an off state of the motor. A robot made up of. The drive circuit control section controls at least a portion of the plurality of upper arm side switching elements or at least a portion of the plurality of lower arm side switching elements to be in an ON state when controlling the tilting of the robot main body during an abnormal stop. 2. The robot according to claim 1, wherein the robot is configured to perform control to reduce the braking force of the dynamic brake until the motor stops by alternately repeating an off state and an off state. The drive circuit section is provided individually for each of the plurality of motors provided for each of the plurality of joints,
When stopping the motor in the event of an abnormal stop, the drive circuit control section controls at least a portion of the plurality of upper arm side switching elements or the plurality of lower arm side switching elements of the drive circuit section provided for each motor. 3. The dynamic brake according to claim 1, wherein the braking force of the dynamic brake for the plurality of motors is individually controlled by alternately repeating an on state and an off state of at least some of the switching elements. The robot described. When stopping the motor in the event of an abnormal stop, the drive circuit control section controls at least a portion of the plurality of upper arm side switching elements or the plurality of lower arm side switching elements of the drive circuit section provided for each motor. By alternately repeating on and off states of at least some of the switching elements, some of the plurality of joints are controlled to reduce the braking force of the dynamic brake more than other joints. 4. The robot according to claim 3, comprising: The robot according to claim 4, wherein the joint to which the braking force is reduced includes at least one of a knee joint and a shoulder joint. The method is configured to perform control to reduce the braking force of the dynamic brake of at least one of the knee joint or the shoulder joint based on position information of the knee joint and position information of the shoulder joint. The robot according to item 5. 7. The robot according to claim 1, wherein the robot main body includes a humanoid robot main body having a plurality of joints corresponding to a plurality of human joints. A robot body including multiple joints,
a plurality of motors provided in each of the plurality of joints;
a drive circuit unit that drives the motor by supplying three-phase AC power to windings of the motor and operates a dynamic brake on the motor;
a drive circuit control unit for controlling the drive circuit unit and the braking force of the dynamic brake by the drive circuit unit;
a detection unit for detecting at least one of a voltage and a current of a power supply path that supplies power to the motor ;
The drive circuit section includes a plurality of upper arm side switching elements forming an upper arm and a plurality of lower arm side switching elements forming a lower arm,
The drive circuit control section is configured to stop at least one of the plurality of motors during an abnormal stop based on at least one of the voltage and current of the power supply path detected by the detection section. By alternately repeating the on state and the off state of at least some of the plurality of upper arm side switching elements or at least some of the plurality of lower arm side switching elements, the dynamic state is maintained until the motor stops. A robot configured to perform feedback control to reduce the braking force of the brake. The drive circuit control section, when stopping the motor at the time of an abnormal stop, based on a comparison between at least one of the voltage and current of the power supply path detected by the detection section and a predetermined threshold value, By alternately repeating on and off states of at least some of the plurality of upper arm side switching elements or at least some of the plurality of lower arm side switching elements, the dynamic brake is maintained until the motor stops. The robot according to claim 8, wherein the robot is configured to perform feedback control to reduce braking force. The drive circuit control unit is configured to control the drive circuit control unit, when at least one of the voltage and current of the power supply path detected by the detection unit exceeds the predetermined threshold value when stopping the motor during an abnormal stop. At least a portion of the plurality of upper arm side switching elements or at least a portion of the plurality of lower arm side switching elements are turned on, and at least one of the voltage and current of the power supply path is equal to or lower than the predetermined threshold value. The braking force of the dynamic brake is reduced until the motor stops by turning off at least a portion of the plurality of upper arm side switching elements or at least a portion of the plurality of lower arm side switching elements. The robot according to claim 9, wherein the robot is configured to perform feedback control. a humanoid robot body including the plurality of joints corresponding to the plurality of human joints;
a plurality of motors provided in each of the plurality of joints;
a drive circuit unit that drives the motor by supplying three-phase AC power to windings of the motor and operates a dynamic brake on the motor;
a drive circuit control section for controlling the drive circuit section and controlling the braking force of the dynamic brake by the drive circuit section;
The drive circuit section includes a plurality of upper arm side switching elements forming an upper arm and a plurality of lower arm side switching elements forming a lower arm,
When stopping at least one of the plurality of motors during an abnormal stop, the drive circuit control section controls at least a portion of the plurality of upper arm side switching elements or at least one of the plurality of lower arm side switching elements. Control is performed to reduce the braking force of the dynamic brake until the motor stops so that the posture of the humanoid robot main body gradually changes by alternately repeating an on state and an off state of the motor. A humanoid robot configured as follows. A method for controlling the fall of a robot including multiple joints,
detecting at least one of the voltage and current of a power supply path that supplies power to a plurality of motors provided in each of the plurality of joints;
The motors are driven by supplying three-phase AC power to the windings of the plurality of motors based on at least one of the detected voltage and current of the power supply path, and Alternating between an on state and an off state of at least some of the plurality of upper arm side switching elements or at least some of the lower arm side switching elements included in a drive circuit unit that operates a dynamic brake for at least one of the plurality of upper arm side switching elements. A method for controlling the fall of a robot, comprising the step of performing feedback control to reduce the braking force of the dynamic brake until the motor stops so that the posture of the robot gradually changes by repeating the feedback control . A method for controlling the fall of a robot including multiple joints,
detecting at least one of the voltage and current of the power supply path by a detection unit for detecting at least one of the voltage and current of the power supply path that supplies power to the motor;
The motors are driven by supplying three-phase AC power to the windings of the plurality of motors based on at least one of the detected voltage and current of the power supply path, and Alternating between an on state and an off state of at least some of the plurality of upper arm side switching elements or at least some of the lower arm side switching elements included in a drive circuit unit that operates a dynamic brake for at least one of the plurality of upper arm side switching elements. A method for controlling the fall of a robot, comprising the step of repeatedly performing feedback control to reduce the braking force of the dynamic brake until the motor stops.

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