CN110123539A - A kind of novel stair climbing wheelchair robot - Google Patents

Abstract

The invention discloses a novel stair-climbing wheelchair robot, which comprises: a positioning mechanism and a climbing mechanism. The positioning mechanism is composed of two sets of mutually hinged parallelogram mechanisms and a first electric push rod. The parallelogram mechanisms have four sets It is composed of rods hinged to each other and in the shape of a parallelogram; the climbing mechanism includes: a bracket, a front wheel assembly and a rear wheel assembly, the bracket is provided with two groups, and the rear wheel assembly includes: a mounting frame, a second An electric push rod and a climbing rod are relatively slidably connected to the installation frame. The stair-climbing wheelchair robot of the present invention uses a double parallelogram mechanism as a positioning mechanism, and forms a climbing mechanism with an electric climbing rod. Through the mutual cooperation of the two mechanisms, the climbing of the stairs can be completed, and the goal of "facing the upstairs when going up the stairs, and facing the downstairs when going down the stairs" can be achieved, so that the way the wheelchair goes up and down the stairs is more in line with the logical thinking of daily sports and improves the user's mobility. comfort.

Description

A new stair-climbing wheelchair robot

technical field

The invention relates to a climbing robot, in particular to a novel stair climbing wheelchair robot.

Background technique

The aging of China's population continues to deepen. Statistics show that in 2014, the number of people over the age of 65 in China reached 137.55 million, accounting for 10.1% of the country's total. On the other hand, the number of persons with disabilities has also increased significantly. If supplemented with auxiliary stair-climbing equipment such as stair-climbing wheelchairs, the elderly and disabled people will be more comfortable facing the stairs.

The research on stair-climbing devices in foreign countries started relatively early. Generally speaking, according to the principle of stair-climbing function realization, it can be divided into wheel-type, crawler-type, step-supporting and other additional auxiliary stair-climbing devices.

For the wheel set type stair climbing device, the movement modes of the small wheels are different when walking on flat ground and climbing stairs: when walking on flat ground, each small wheel rotates on its own axis, and when climbing stairs, each small wheel revolves around the central axis together. However, wheeled wheelchairs have some disadvantages. First, each wheel in a wheel set must have its own drive train, so wheelchairs can be very bulky. Second, and more fatally, the geometry of the wheel set cannot be adjusted to a stepped geometry. In addition, the center of gravity of the planetary gear mechanism fluctuates greatly when going up and down stairs, which has a great impact on the comfort of users.

The stair-climbing wheelchair with the track-type mechanism is widely used. Compared with the wheel-set mechanism, its motion mode is more continuous and the transmission efficiency is relatively high. In the process of going up and down the stairs, the center of gravity of the wheelchair always moves along a straight line parallel to the line along the steps of the stairs, the fluctuation of the center of gravity is small, and the movement is stable. In addition, the crawler structure has the advantages of simple control and the ability to adapt to stairs and obstacles of various sizes. But generally speaking, crawler wheelchairs are not suitable for use in environments where the edge of the stairs is too smooth and the slope is greater than 30° to 35°. In addition, crawler wheelchairs are easy to damage the edge of the stairs when climbing stairs, and the later maintenance costs are relatively high. These series of problems all restrict the development of crawler wheelchair.

The step-support stair-climbing wheelchair is the one with higher safety, the most complicated transmission mechanism and the most complicated control among all forms of stair-climbing wheelchairs. The climbing mechanism of the step-support type stair-climbing wheelchair is composed of a link mechanism. This type of stair-climbing wheelchair mainly includes two types of leg system and wheel-leg hybrid system.

In addition, most wheel-legged wheelchair robots currently on the market face the stairs with their backs when climbing stairs, which is contrary to the logic of people’s daily movement, which reduces the comfort of users and affects the experience of passengers to a certain extent.

Contents of the invention

The object of the present invention is to provide a novel stair-climbing wheelchair robot to solve the problems raised in the above-mentioned background technology.

To achieve the above object, the present invention provides the following technical solutions:

A new type of stair-climbing wheelchair robot, comprising: a positioning mechanism and a climbing mechanism, the positioning mechanism is composed of two groups of mutually hinged parallelogram mechanisms and a first electric push rod, and the described parallelogram mechanisms have four groups of mutually hinged and formed Composed of rods in the shape of a parallelogram, the parallelogram mechanism is connected to the seat, the tail ends of the first electric push rod are respectively hinged with two sets of parallelogram mechanisms, and the top end is connected to the seat;

The climbing mechanism includes: a bracket, a front wheel assembly and a rear wheel assembly, the brackets are provided with two groups, respectively connected to the parallelogram mechanism, and the front wheel assembly and the rear wheel assembly are respectively fixed on the two groups of brackets At the bottom, the front wheel assembly and the rear wheel assembly all include: a mounting frame, a second electric push rod, and a climbing rod. Rotation connection, the climbing rod and the installation frame are relatively slidable connection; the bottom of the two sets of brackets are respectively equipped with a rotatable front wheel set and a rear wheel set, and the front wheel set is provided with a steering mechanism and a driving mechanism, which are respectively used to control The front wheelset steers and drives the movement of the front wheelset.

As a further solution of the present invention: the steering mechanism includes a first steering gear and a steering linkage, and the steering linkage is respectively connected to the first steering gear and the front wheel set.

As a further solution of the present invention: the drive mechanism includes a motor and a bevel gear set, and the motor is connected to the rotating shaft of the front wheel set through the bevel gear set.

As a further solution of the present invention: the front wheel set and the rear wheel set are provided with a screw mechanism, the screw mechanism shown includes a second steering gear, a lead screw, a slider and a slide rail, and the slide rail is fixedly arranged on Below the installation frame, the slider is slidably arranged on the slide rail, the screw is installed at the bottom of the installation frame and connected with the second steering gear, the screw runs through the threaded hole in the slider, and the front wheel set is installed at the bottom of the slider or the rear wheel set.

As a further solution of the present invention: the climbing pole is inclined at an angle of 35° relative to the support.

As a further solution of the present invention: a rubber sleeve is respectively arranged on both sides of the bottom end of the climbing rod in the rear wheel assembly, a strut is fixedly arranged on the climbing rod in the front wheel assembly, and a rubber sleeve is respectively arranged on both sides of the bottom of the strut. set.

Compared with the prior art, the beneficial effects of the present invention are: the stair-climbing wheelchair robot of the present invention is designed with the mechanism motion principle of the stair-climbing wheelchair, uses a double parallelogram mechanism as a positioning mechanism, and forms a climbing mechanism with an electric climbing rod. Through the mutual cooperation of the two mechanisms, the climbing of the stairs can be completed, and the goal of "facing the upstairs when going up the stairs, and facing the downstairs when going down the stairs" can be achieved, so that the way the wheelchair goes up and down the stairs is more in line with the logical thinking of daily sports and improves the user's mobility. comfort.

Description of drawings

Fig. 1 is a structural diagram of the present invention.

Fig. 2 is a schematic diagram of the screw mechanism in the present invention.

FIG. 3 is an enlarged structure diagram at point A in FIG. 1 .

Fig. 4 is a structural diagram of the front wheel assembly in the present invention.

Fig. 5 is a schematic diagram of the PID control system of the front and rear positioning push rods in the present invention.

Fig. 6 is a schematic diagram of the PID control system of the front and rear climbing push rods in the present invention.

Fig. 7 is a schematic diagram of the driving PID control system of the driving mechanism in the present invention.

Fig. 8 is a schematic diagram of the step-up process of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Please refer to Fig. 1～4, in the embodiment of the present invention, a kind of novel stair-climbing wheelchair robot comprises: positioning mechanism, climbing mechanism, and described positioning mechanism is composed of two groups of mutually hinged parallelogram mechanism 21 and first electric push rod 22, the parallelogram mechanism 21 is composed of four sets of rods that are hinged to each other and in the shape of a parallelogram. Hinged, the top end is connected to the seat 1, and the two sets of parallelogram mechanisms 21 are respectively driven to move through the first electric push rod 21. During the driving process, the characteristics of the parallelogram mechanism can be used to keep the seat 1 always level. On the one hand, the posture of the wheelchair can be changed to realize the relative movement of the wheels within a certain range.

Described climbing mechanism comprises: support 4, front wheel assembly and rear wheel assembly, described support 4 is provided with two groups, is connected with parallelogram mechanism 21 respectively, and described front wheel assembly and rear wheel assembly are respectively fixed on The bottom of the two groups of supports 4, the front wheel assembly and the rear wheel assembly all include: a mounting frame 31, a second electric push rod 32, a climbing rod 33, the mounting frame 31 is fixedly connected with the support 4, and the second electric push rod The two ends of the rod 32 are rotatably connected with the climbing rod 33 and the bracket 4 respectively, and the climbing rod 33 is relatively slidably connected with the mounting frame 31, and the climbing rod 33 is inclined at an angle of 35° relative to the bracket 4. In addition, the climbing rod 33 on the rear side A rubber sleeve 331 is respectively arranged on both sides of the bottom end of the bottom end, and a strut 332 is fixedly arranged on the climbing rod 33 on the front side, and a rubber sleeve 331 is respectively arranged on both sides of the bottom of the strut 332; The front wheel set 54 and the rear wheel set 35 are provided with a steering mechanism and a driving mechanism on the front wheel set 54, and the steering mechanism includes a first steering gear 52 and a steering link 55, and the steering link 55 is connected to the first steering link 55 respectively. A steering gear 52 is connected with the front wheel set 54, and the front wheel set 52 is driven by the first steering gear 52 to realize turning. The drive mechanism includes a motor 53 and a bevel gear set 51. The rotating shaft is connected in order to drive the front wheel set 54 to rotate.

In order to prevent the wheels from interfering with the steps during the climbing process, a lead screw mechanism 34 is provided on the front wheel set 54 and the rear wheel set 35, and the shown lead screw mechanism 34 includes a second steering gear 341, a lead screw 342, Slider 343 and slide rail 344, described slide rail 344 is fixedly arranged below mounting frame 31, and described slide block 343 is slidably arranged on slide rail 344, and described lead screw 342 is installed in mounting frame 31 bottom and is connected with the second rudder Machine 341 is connected, and leading screw 342 runs through the threaded hole in the slide block 343, and front wheel set 54 or rear wheel set 35 are installed at the bottom of slide block 343.

Figure 5 shows the schematic diagram of the PID control system of the first electric push rod 21. For the electric push rod of the front and rear positioning mechanism, the model is simplified as applying a pair of interaction forces to the push rod head and the push rod base, and the PID input is the push rod The elongation error of the rod, the output is the magnitude of the thrust. Since the steady state of the system must be maintained with a certain amount of force, in order to prevent the wheelchair from vibrating violently and overshooting during the start-up phase, an initial value of force F0 is superimposed on the PID output signal to make the PID reach a steady state faster.

Figure 6 is a schematic diagram of the PID control system of the second electric push rod 33, the electric push rod control of the climbing rod 33, the controlled quantity and the actuator are the same as the first electric push rod 21, due to the climbing stage and the non-climbing stage The force of the putter is completely different, and it belongs to two different systems. Therefore, the parameters of the climbing stage and the non-climbing stage are set separately, and the integral item is re-initialized when the two stages are converted.

7 is a schematic diagram of the PID control system of the driving mechanism of the front wheel set 54, the input of the PID control system is the speed deviation, and the output is the torque of the front wheel set 54. In order to reduce the wheel speed overshoot, the integral separation PID control algorithm is adopted. In order to avoid accidents such as wheel stalling, the integral term is limited. In addition, limited by the maximum torque of the wheel motor, the torque output should also be limited. Before carrying out the torque output, it should also be judged whether the current state of the front wheel set 54 is in contact with the ground, if the wheels are suspended in the air, the torque output is zero.

The step-up process of the present invention is shown in Figure 8. At the beginning, the wheelchair moved forward, and when the wheels approached the obstacle, the wheelchair stopped moving;

The climbing rod 33 on the front wheel group 54 side moves downwards and contacts with the ground, and the weight of the wheelchair is transferred to the climbing rod 33;

The wheel moves upwards to the right under the drive of the climbing rod 33, and at the same time, the screw rod 342 drives the slider 343 to drive the front wheel group 54 to move backwards to avoid interference with the steps, and finally the front wheel group 54 climbs up the steps with an upward synthetic movement ;

When the height of the front wheel set 54 is sufficient, the screw mandrel 342 drives the wheels to move forward to the initial position, the climbing rod 33 shrinks, the front wheel set 54 contacts the first step, and the weight of the wheelchair is transferred to the wheels again. Climbing a step, it can be seen that during the whole climbing process, there are always four contact points between the wheelchair and the ground, which is conducive to the system being in a stable state all the time.

The process of descending the stairs is similar to the above process. The process of descending the stairs is that the rear wheel group 35 is facing the forward direction. When the rear wheel group 35 is close to the edge of the step, the climbing rod 33 is launched, climbs, and the 33 contacts the ground, and the screw mandrel 342 drives the rear wheel group 35 moves forward to avoid interfering with the steps, then the climbing rod 33 shrinks, and when the wheels are in contact with the ground, the wheels return to their original state.

It will be apparent to those skilled in the art that the invention is not limited to the details of the above-described exemplary embodiments, but that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Accordingly, the embodiments should be regarded in all points of view as exemplary and not restrictive, the scope of the invention being defined by the appended claims rather than the foregoing description, and it is therefore intended that the scope of the invention be defined by the appended claims rather than by the foregoing description. All changes within the meaning and range of equivalents of the elements are embraced in the present invention. Any reference sign in a claim should not be construed as limiting the claim concerned.

In addition, it should be understood that although this specification is described according to implementation modes, not each implementation mode only includes an independent technical solution, and this description in the specification is only for clarity, and those skilled in the art should take the specification as a whole , the technical solutions in the various embodiments can also be properly combined to form other implementations that can be understood by those skilled in the art.

Claims (6)

1. a kind of novel stair climbing wheelchair robot, comprising: positioning mechanism, climbing mechanism, it is characterised in that: the positioning mechanism It is made of two groups of parallelogram mechanisms being hinged (21) and the first electric pushrod (22), the parallelogram mechanism (21) it is hinged by four groups and the bar of parallelogram shape forms, parallelogram mechanism (21) connecting chair (1) is described First electric pushrod (21) tail end respectively with two groups of parallelogram mechanisms (21) hingedly, top is connected on seat (1)；

The climbing mechanism includes: bracket (4), preceding wheel assembly and rear wheel assembly, and the bracket (4) is arranged two groups, respectively with it is flat Row quadrangular mechanism (21) connection, the preceding wheel assembly and rear wheel assembly are individually fixed in two pack supports (4) bottom, preceding wheel assembly It include: mounting rack (31), the second electric pushrod (32), the bar that climbs (33) with rear wheel assembly, the mounting rack (31) and bracket (4) it is fixedly connected, the second electric pushrod (32) both ends are rotatablely connected with the bar that climbs (33) and bracket (4) respectively, described to climb Rising stem (33) and mounting rack (31) are with respect to slidable connection；Two pack supports (4) bottom is separately installed with rotatable front wheels (54) and rear wheels (35) steering mechanism and driving mechanism, are set on the front wheels (54), are respectively used to control front wheels (54) turn to and drive front wheels (54) movement.

2. a kind of novel stair climbing wheelchair robot according to claim 1, it is characterised in that: the steering mechanism includes First steering engine (52) and steering link (55), the steering link (55) connect with the first steering engine (52) and front wheels (54) respectively It connects.

3. a kind of novel stair climbing wheelchair robot according to claim 1, it is characterised in that: the driving mechanism includes Motor (53) and bevel gear set (51), motor (53) are connect by bevel gear set (51) with the shaft of front wheels (54).

4. a kind of novel stair climbing wheelchair robot according to claim 1, it is characterised in that: the front wheels (54) and It is respectively provided in rear wheels (35) screw mechanism (34), shown screw mechanism (34) includes the second steering engine (341), lead screw (342), slides Block (343) and sliding rail (344), the sliding rail (344) are fixedly installed below mounting rack (31), and sliding block (343) sliding is set It sets on sliding rail (344), the lead screw (342) is mounted on mounting rack (31) bottom and connect with the second steering engine (341), lead screw (342) through the threaded hole in sliding block (343), front wheels (54) or rear wheels (35) are installed in sliding block (343) bottom.

5. a kind of novel stair climbing wheelchair robot according to claim 1, it is characterised in that: the bar that climbs (33) phase 35 ° of angles are tilted to bracket (4).

6. a kind of novel stair climbing wheelchair robot according to claim 1, it is characterised in that: climbed in the rear wheel assembly The bottom end two sides of rising stem (33) are respectively arranged a rubber sleeve (331), climb in preceding wheel assembly and are fixedly installed strut on bar (33) (332), a rubber sleeve (331) are respectively arranged in strut (332) two sides of the bottom.