JPH03500452A - Obstacle detection device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Obstacle detection device 〔Technical field〕 The present invention relates to a vehicle sensor, and more specifically, detects obstacles on the path of a work vehicle. Regarding vehicle sensors that can be used.

[Background technology]

Lift trucks, platform trucks, AGV and other work vehicles It is used to transport cargo in factories and warehouses. Under such a working environment, There are often obstacles in the path of the vehicle, and several work vehicles are not mutually exclusive. They are often driven in close proximity at all times. For this reason, detection is required to avoid collisions. system is desired. This is particularly desired when using unmanned vehicles.

U.S. Pat. No. 4,447,800 to Kasuya et al. discloses an obstacle detection system that uses optical transmitting means, the means reflecting the optical energy of the potential obstruction. and sends it to the optical receiving means. However, due to limited scanning ability, This system is not suitable for low speed vehicles. For low-speed vehicles, a wide area relatively close to the vehicle is recommended. A system that scans a wide range of areas is needed.

Although some patents point out the need to scan a wide area, This has not been resolved due to cost issues.

For example, U.S. Pat. No. 3,842,397 discloses a distance sensing system that It uses multiple fixed ultrasonic sensors mounted on a surface. however, This system also uses a lot of hardware and is therefore expensive. Also, - or By scanning forward and backward using transceivers on two sides, a wide scanning area can be covered. There are also inventions that try to secure. For example, U.S. Pat. No. 4 of Ian J., Dawson et al. , No. 706,772 (dated November 17, 1987) opens such a system. It shows. These systems are equipped with transceivers needed to scan a specific area. Although the number of bars may be small, the manufacturing process is quite complicated. These systems are Contains cumbersome linkage and moving equipment, and is a source of bending of the bonding wires as the sensor moves. cause As a result, these systems are prone to failure and are also expensive to implement. It becomes a cost.

Therefore, there is a need for a vehicle front obstacle detection device that solves the above-mentioned problems. Main departure This was done to achieve this purpose.

[Contents of the invention]

To achieve this objective, the present invention provides a detection system for detecting obstacles on the path of a work vehicle. Provide equipment. This sensing device is equipped with a transducer, which A ducer generates radiant energy with a central axis of propagation, and the reflected radiation It receives energy and freely transmits an obstacle detection signal in response to the reception. rotate The flexible reflector emits radiant energy radially outward from the work vehicle in a controlled manner. , receives reflected radiant energy that has been reflected along approximately the same path. this reflector is rotatable around the central axis of rotation, and is further rotatable around the central axis of rotation. It is equipped with an optical reflection member. The encoder has an optical reflective member that rotates around the central axis of rotation. can be freely controlled in response to being located at any one of a plurality of predetermined positions. emit a signal. The zone control logic receives the obstacle detection signal and the tolerance signal and Emit a control signal.

The present invention also provides an arrangement comprising a vehicle frame including spaced apart first and second side walls. Provide commercial vehicles. The vehicle frame has a radiant energy receiving part and a radiating part. Transducer is installed. The radiation part is a radiation element with a central axis of propagation. The receiver receives the reflected radiant energy and receives the reflected radiant energy. In response to this, an obstacle detection signal is issued. The reflector has a central axis of rotation and the transformer The vehicle is located at a suitable location to intercept the radiant energy emitted by the deuser radiator. It is rotatably attached to the frame. The encoder is placed between the light source and the receiver. The device has a rotatable member located thereon, the member being optically encoded. The said d The encoder is connected to the vehicle frame and rotates according to the predetermined position of the rotatable member. and is configured to issue a permission signal. Motor is optically coded with reflector It is equipped with a rotating shaft that is connected to a I'm being kicked. The zone control logic receives the obstacle detection signal and the tolerance signal; Emit vehicle control signals.

Brief description of the drawing For a better understanding of the invention reference is made to the drawings.

FIG. 1 is a schematic diagram of a first embodiment of the invention, and FIG. 2 is an optically encoded rotary motor. A plan view of the first embodiment of the existing components, FIG. 3 is scanned by the first embodiment. FIG. 4 is a schematic diagram showing the second embodiment of the present invention, and FIG. 5 is a schematic diagram showing the area. A plan view of the second embodiment of the rotatable member that is made into a card, and FIG. 6 is the second embodiment. Schematic diagram showing the area to be scanned according to the example, FIG. 7 is a schematic diagram showing a part of the first embodiment It is.

〔Example〕

FIG. 1 shows a device 10 for detecting obstacles on the path of a work vehicle 12. ing. The apparatus 10 includes spaced apart first and second cages, and the transducer 14 A receiving section 14A that receives radiant energy and emits radiant energy around the central axis of propagation. It has a radiation part 14B. Preferably the radiant energy is an infrared signal.

The transducer 14 transfers radiant energy to a rotatable transducer having an optical reflecting member 17. The light is emitted toward the reflector 16. Optical reflective member 17 is shown here as mirror 18. and is attached to one end of a rotating shaft 20 having a rotation center axis. Axis of rotation At the other end of 20 is a movable means that can rotate the rotating shaft 20 around its central axis. 22 is attached. In the first embodiment, the mirror 18 is infrared rays. It is attached to the rotating shaft 20 so that the signal is emitted outward from the work vehicle 12 substantially horizontally. I'm being kicked.

When the movable means 22 rotates the rotatable reflector 16 at a predetermined speed, the mirror 18 emits light. Changes the direction of reflection of the emitted radiant energy.

In other words, when the reflector 16 rotates once, the emitted radiant energy is spread over a range. At the same time, the radiation that hits the obstacle and is reflected back to the mirror 18 The energy returns to the transducer 14 via the mirror 18. receive this radiant energy The detected transducer 14 emits a signal indicating that an obstruction has been detected.

An encoder 24 is provided between the movable means 22 and the mirror 18 inside the device 10. Ru. Encoder 24 has an optically encoded rotatable member 26. Department The member 26 is preferably driven by the rotating shaft 20 and is coaxial with the rotating shaft 20. stomach. When the rotating shaft 20 rotates, the member 26 similarly rotates. As shown in Figure 2 , the optically encoded rotatable member 26 is arranged according to a predetermined pattern. It has alternating portions that do not allow light to pass through (hatched portions) and portions that allow light to pass through. Also, the As shown in FIG. 7, the encoder 24 includes a stationary optical sensor 27. still light The optical sensor includes a light emitting diode (LED) 29 as a preferred light source 28; A phototransistor 31 as a new light receiver 30 is provided.

Referring to FIG. 7, inside the encoder 24, light is emitted from the LED 29. The generated light energy is directed to phototransistor 31. LED29 and photo truck At least a portion of the member 26 is located between the member 26 and the register 31. LED2 The first conductive wire 9 has is connected to a positive voltage source via a bias resistor 29A, Bias resistor 29A allows the appropriate current to flow through LED 29. Second conductor of LED29 is grounded. The collector of the phototransistor 31 is connected to a positive voltage source; The emitter is the first of AND gates 33 as the preferred zone logic control circuit 32. It is connected to one input terminal and is grounded via a resistor 31A.

The second terminal of the AND gate 33 is the output of the receiving section 14B of the transducer 14. Connected to the terminal. The output terminal of the AND gate 33 is connected to the vehicle logic circuit 34. It is tied.

An optically encoded light source located between the LED 29 and the phototransistor 31 If the member 26 is a part that allows light to pass through, the light emitted by the LED 29 will pass through the light. Logic 1 signal on the emitter output terminal. create a number.

This allows the logic signal on the output terminal of AND gate 33 to be transduced. The signal is made to match the logic signal on the output terminal of the receiver 14B of the sensor 14. In other words, If the output signal from the Lance Duplexer 14 is "logic 1", the AND gate 33 The output signal of If the logic is 0, the output signal of the AND gate 33 will also be 0.

However, if the member 26 is a part that does not transmit light, the LED 29 The light from the phototransistor 31 does not hit the base of the phototransistor 31. As a result of this, The emitter terminal of the phototransistor 31 is grounded via a resistor 31A. Therefore, it has a "logic 0" signal. This allows the transducer 14 to Regardless of whether the signal is "logic 1" or "logic 0", AND The output terminal of the gate 33 becomes "logic O".

Therefore, the light passing portion of the member 26 is between the LED 29 and the phototransistor 31. The device 10 only indicates the presence of a detected obstacle when the device 10 is located at the is energized by As will be obvious to those skilled in the art, the portion of member 26 that does not transmit light Obstacles only exist when located between the LED 29 and the phototransistor 31. It is easy to configure the device IO so that its presence is indicated.

The arrangement pattern of light-transmitting parts and light-blocking parts is determined by the location of the member 26 and therefore the mirror 18. Only when the phototransistor 31 rotates to a fixed position is determined to emit a "logic 1" signal. The predetermined position The scanning area is not behind and outside the vehicle 12, but in front of and immediately adjacent to the vehicle 12. It can be determined as follows. The predetermined position X in the first embodiment is as shown in FIG. It was decided that.

When the mirror 18 scans the range of angle A', the radiant energy reaches the front of the vehicle 12. Since the received reflected radiant energy indicates the presence of an obstacle, the device 10 2 Detect obstacles in front. The area scanned while the mirror 18 moves within the range of angle A' The area is represented by the shaded area within angle A', and this area includes the front of the vehicle 12. However, the area near the vehicle 12 is not included.

If the mirror 18 scans the range of angles B' and B', the desired scanning area is already The received reflected radiation energy can be ignored. mirror 18 by ignoring the radiant energy received while traveling through the range of angles B' and B'. Therefore, the device 10 cannot detect obstacles near the vehicle 12 except in front of the vehicle 12. do not have. Therefore, the vehicle 12 is able to avoid obstacles such as walls and other vehicles. It is possible to operate without erroneous detection and display.

In the range of angles A' and A', the radiant energy and the received radiant energy is reflected by the first and second fixed reflectors 36,38 so that the device 10 detecting an obstacle in front of the 12 spaced apart first and second side walls 13A, 13B; . Radiant energy is radiated outward from the corners of vehicle 12. fixed reflection The device 10 can be connected to either the first or second side wall 13A, 13B by means of the container 36.38. approaches the vehicle 12 and detects objects near the front of the vehicle 12, such as humans or other vehicles. . The area scanned while mirror 18 travels through angles A' and A+j'' is shown in FIG. is represented by the shaded area including angles A' and A'. Area represented by diagonal lines are respectively forward of either the right or left corner of the vehicle 12 and the angle A ' and the area not surrounded by the range including ' and the first or second side wall 13A, 13B Including the immediate outer area. The device 10 is configured such that the mirror 18 is oriented in a direction opposite to the traveling direction of the vehicle 12. When scanning the range of angle B' in , detected obstacles can be displayed. I can't.

In a second embodiment shown in FIG. 4, a transducer 14' and a rotatable The reflector 16' means that the radiant energy is directed downward at an angle from the central axis of rotation of the reflector 16'. When the reflector 16' rotates, the radiant energy is will be radiated along a conical path. In this example, FIG. It is desirable to scan the entire semicircle in the direction of vehicle travel, which is within the range of angle A.

Therefore, the light-transmitting portion of the optically encoded rotatable member 26' and the light-transmitting portion of the optically encoded rotatable member 26' The arrangement with the parts not shown is the same as that shown in FIG. emit radiant energy The output of the transducer 14' is determined when the transducer 14' detects an obstacle near the ground. is detected, but the ground itself is not detected. Radiant energy is directed downwards radiated, the device 10 clears any obstacles between the reflector 16' and the ground. Detects regardless of height from above.

[Industrial applicability]

[Device according to the present invention] 0 is when an obstacle is detected in the path of a running vehicle. But it gives a signal. Such devices are especially suitable for unmanned vehicles used in factories and warehouses. It is useful for

In a typical application, the work vehicle 12 transports cargo and transports cargo within a factory. Lance ducer 14 emits a beam of radiant energy and rotates the beam. Aim at reflector 16. Radiant energy is radiated outward from vehicle 12 by reflector 16. shot. When the vehicle 12 approaches an obstacle, the emitted radiant energy is reflected. Return to gun 16. [Rotating reflector] 6 transduces the reflected radiant energy. Return to user 14, transducer]4 to the first input terminal of AND gate 33 Sends a "logic 1" signal.

At the same time, member 26 rotates between LED 29 and phototransistor 31. anti If the projector 16 is scanning the desired area, the LED 29 and phototransistor The part of the member 26 located between the member 31 and the member 31 is a part through which light passes. LED29 emits The light hits the base of the phototransistor 31, and the phototransistor 31 ``Logic 1'' is placed on the emitter conductor connected to the second human power terminal of the ND gate 33. generate a signal. Both input terminals of AND gate 33 are F logic 1. In response, a “logic 1” output signal is sent to the vehicle logic circuit 34; Vehicle logic circuit 34 causes vehicle 12 to perform predetermined actions to avoid a collision. hindrance If the object is not present, the radiant energy will not be reflected back to the transducer 14; Its output terminal will get a "logic 0" signal.

The output terminal of the AND gate 33 also becomes "logic 0" accordingly, and the vehicle 12 Continue to operate without changing course.

The reflector 16 scans an undesired area, for example, an area in the direction opposite to the vehicle traveling direction. If there is a gap between the LED 29 and the phototransistor 31 of the member The part that is transparent is the part that does not allow light to pass through. The light emitted by LED29 is a phototransistor Since the base of 31 is not reached, the signal sent to AND gate 33 is "logic 0". ”. Therefore, the output of AND gate 33 is also a "logic 0" and the device 10 will not be able to send that an obstacle has been detected.

Other advantages and uses of the present invention other than those described above can be understood from the drawings and specification. .

international search report international search report PCT/US 88103573

Claims (1)

[Claims] (1) Mounted on a work vehicle (12) to detect obstacles in the path of the vehicle (12) A device (10) for knowing, Generates radiant energy with a central axis of propagation and receives reflected radiant energy A transducer ( 14) and controlling the radiant energy radially outward from the vehicle (12). A rotation that radiates freely and receives radiant energy that is reflected along approximately the same path. A freely rotatable reflector (16), comprising a central axis of rotation and an optical element rotatable around the rotation axis. a reflector (16) having a reflective member (17); The optical reflecting member (17) is located at any of a plurality of predetermined positions around the rotation center axis. an encoder (24) that controllably issues a permission signal in response to the position of the , receiving the obstacle detection signal and the acceptance signal; Zone control that issues a vehicle control signal in response only when a signal is present at the same time. A device (10) comprising a control logic (32). (2) Controllably rotate the optical reflection member (17) around the rotation center axis. The device (1) according to claim 1, characterized in that it comprises movable means (22) for 0). (3) The optical reflecting member (17) is positioned in front at a predetermined angle from the rotation center axis. a mirror (18) connected to said movable means (22), said transducer ( 14) is optically connected to the mirror (18). (10). (4) The central axis of propagation of the radiant energy is from the mirror (18) to the reflector ( Claim 17), characterized in that the process proceeds along a first plane substantially perpendicular to the axis of rotation of claim 17). ) described device (10). (5) receiving said radiant energies and accordingly directing said radiant energies in their progress; first and second fixed reflectors (36, 38) that are redirected along the road; first and second fixed reflectors (3) spaced apart from each other and from the reflector; 6, 38). Device (10) according to claim 4, characterized in that it comprises: 6, 38). (6) The vehicle (12) has first and second side walls (13A, 13B), and the vehicle (12) has first and second side walls (13A, 13B); The reflector (16) is located approximately equidistantly between the two side walls (13A, 13B). and the first and second fixed reflectors (36, 38) are located on the side walls (13A, 1 3B) on the opposite side wall of the reflector (16) adjacent to each fixed reflector. The containers (36, 38) are connected to the front side walls (13A, 38) of the vehicle (12) and the adjacent side walls (13A, 38). 13B), the redirected radiant energy being directed substantially parallel to each of the Device (10) according to claim 5, characterized in that: (7) The central axis of propagation of the radiant energy is from the mirror (18) to the reflector. (16) downward along a partially conical passage branching at an angle from the axis of rotation. Device (10) according to claim (3), characterized in that it proceeds. (8) The encoder (24) is an optically encoded rotatable member (26). ) and a fixed optical sensor (27), said member (26) being arranged according to a predetermined pattern. It has a part that allows light to pass and a part that does not allow light to pass, which are arranged as follows. The fixed optical sensor (27) is separated by a light source (28) and the member (26). and a light receiver (30), The member (26) maintains a predetermined relationship with the reflector (16) while moving the movable means ( Device (10) according to claim (2), characterized in that it is connected to (22). (9) The light transmitting portion of the member (26) is connected to the light source (28) and the light receiver (30). ), in which a permissive signal is emitted in response to being located between Apparatus (10) according to claim (8). (10) The zone control logic (32) is configured to control the transducer (14). A first input terminal connected to the encoder (24) and a second input terminal connected to the encoder (24). Claim (1) characterized in that the invention comprises an AND type logic gate (33) that ) described device (10). (11) Vehicle frame with spaced apart first and second side walls (13A, 13B) Mu (12A) and A radiation part (14B) that emits radiation energy having a central axis of propagation, and a radiation part (14B) that emits radiation energy having a central axis of propagation, and a receiving unit (14A) that receives radiant energy and issues an obstacle detection signal in response to the received radiant energy; A radiant energy transducer (14) comprising: (12A) a transducer (14) mounted on the It has a rotation center axis and intercepts the radiant energy radiated by the radiating part (14B). The vehicle frame (12A) is rotatably connected to the vehicle frame (12A) at a position suitable for a reflector (16) arranged between the light source (28) and the receiver (30); a rotatable member (26) encoded in the vehicle frame (12A); an encoder coupled to and emitting a permission signal in accordance with a predetermined position of the member (26); (24) and a rotating shaft (20) connected to the reflector (16) and the member (26); The motor (22) connected to the vehicle frame (12A) and the obstacle detection a signal and the permissible signal, and the permissible signal and the obstacle detection signal are simultaneously received. Zone control logic means (32) for emitting vehicle control signals only if present; A work vehicle (12) consisting of. (12) The motor (22) has the rotatable reflector (16) as the center of rotation. A claim characterized in that the device is configured to be controllably rotated around an axis 11) The work vehicle (12) described above. (13) The rotatable reflector (16) is mounted at a predetermined angle from the rotation axis. and is in optical communication with the transducer (14). A work vehicle (12) according to claim (12). (14) The central axis of propagation of the radiant energy is approximately aligned with the rotation axis of the reflector (16). The device according to claim 13, characterized in that the device is located along a first vertical plane. Commercial vehicles (12). (15) a first part of the vehicle frame (12A) spaced apart from the reflector (16); and first and second fasteners along each of the second spaced apart side walls (13A, 13B). a constant reflector (36, 38) for receiving and responsive to said radiant energy; first and second fixed reactors that redirect the radiant energy along their paths; The working device according to claim (14), characterized in that it is equipped with a gun (36, 38). Vehicle (12). (16) Is the central axis of propagation of the radiant energy the rotation axis of the reflector (16)? extending downwardly along a partially conical channel branching at an angle from the The work vehicle (12) according to claim (13), wherein the work vehicle (12) is characterized by: (17) The member (26) is a part that transmits light arranged according to a predetermined arrangement pattern. and a portion that does not transmit light, and maintains a predetermined relationship with the reflector (16). The working device according to claim 11, characterized in that the rotating shaft (20) is connected to the rotating shaft (20). Vehicle (12). (18) The permission signal indicates that the light-transmitting portion of the member (26) is connected to the light source (28). The light is emitted in response to being located between the light receiver (30) and the light receiver (30). A work vehicle (12) according to claim (17). (19) The zone control logic means (32) is connected to the transducer (14). a first input terminal connected to the encoder (24) and a second input terminal connected to the encoder (24). Claim characterized in that it comprises an AND type logic gate (33) having 11) The work vehicle (12) described above. (20) Vehicle frame with spaced apart first and second side walls (13A, 13B) Mu (12A) and A radiation part (14B) that emits radiation energy having a central axis of propagation, and a radiation part (14B) that emits radiation energy having a central axis of propagation, and a receiving unit (14A) that receives radiant energy and issues an obstacle detection signal in response to the received radiant energy; A radiant energy transducer (14) comprising: (12A) a transducer (14) mounted on the It has a rotation center axis and intercepts the radiant energy radiated by the radiating part (14B). It is rotatably connected to the vehicle frame (12A) at a position suitable for a reflector (16) mounted at a predetermined angle from the central axis; The vehicle frame (12) has a rotating shaft (20) connected to the reflector (16). A) to controllably rotate the reflector (16) and the rotation center axis. a motor (22) arranged between the light source (28) and the light receiver (30); an encoder (24) having a rotatable member (26) encoded with The member (26) has light transmitting portions arranged according to a predetermined arrangement pattern. and a part that does not transmit light, and maintains a predetermined relationship with the reflector (16). and the encoder (24) is connected to the rotating shaft (20). The light transmitting portion is connected to the light source (28) and the light receiver. (30) configured to issue a permissive signal in response to being located between an encoder (24), receiving the obstacle detection signal and the acceptance signal; A zone control logic that emits vehicle control signals only when a signal is present at the same time. A work vehicle according to claim 17, characterized in that the work vehicle ( 12). (21) The central axis of propagation of the radiant energy is approximately aligned with the rotation axis of the reflector (16). The device according to claim 20, characterized in that the device is located along a first vertical plane. Commercial vehicles (12). (22) a first part of the vehicle frame (12A) spaced apart from the reflector (16); and first and second fasteners along each of the second spaced apart side walls (13A, 13B). a constant reflector (36, 38) for receiving and responsive to said radiant energy; first and second fixed reactors that redirect the radiant energy along their paths; The working device according to claim (21), characterized in that it is equipped with a gun (36, 38). Vehicle (12). (23) Is the central axis of propagation of the radiant energy the rotation axis of the reflector (16)? extending downwardly along a partially conical channel branching at an angle from the The work vehicle (12) according to claim (20), wherein the work vehicle (12) is characterized by: