CN204110201U - A kind of multiple degree of freedom running gear for six biped robots - Google Patents

Abstract

The utility model discloses a multi-degree-of-freedom walking system for a hexapod robot, which comprises a first joint, a second joint, a third joint, a fourth joint, a fifth joint, an electronic cabin, a tibia and a foot. The cooperation method of converting the four degrees of freedom can improve the adaptability of the robot to complex terrain such as slopes, narrow roads, ditches, and ridges, making the movement flexible and reducing energy consumption; a harmonic reducer is installed inside the joint, and the reduction ratio is large and accurate. It reduces the design difficulty of the robot control system; the noise is low, the transmission is stable, the titanium alloy material is used, the weight is reduced, the energy is saved, the load capacity is improved, the volume is small, the weight is light, and it is convenient to realize the lightweight of the mechanism; the electronic cabin of the legs can carry information The collection system or the local control system of the legs reduces the complexity of the overall control system of the robot; the parts have high adaptability, which is convenient for parts repair and replacement, and reduces the difficulty of maintenance.

Description

A multi-degree-of-freedom walking system for a hexapod robot

technical field

The utility model relates to a bionic robot, in particular to a multi-freedom walking system for a hexapod robot.

Background technique

In recent years, with the rapid development of bionics theory and computer technology, the research on multi-legged bionic robots, especially the research on hexapod robots, has gradually become the focus of attention. Many universities and research institutions at home and abroad have also successively researched and produced a variety of hexapod bionic robot walking systems with excellent performance.

Genghis, a hexapod robot developed by the Artificial Intelligence Laboratory of the Massachusetts Institute of Technology in 1989, is mainly used for scientific exploration tasks on the surface of extraterrestrial planets. Each leg has two rotational degrees of freedom, is driven by a servo motor based on position feedback, integrates a current measurement unit to obtain torque information, is equipped with two antennae sensors and two single-axis accelerometers, and can walk on complex roads . However, due to the absence of the common joint design of arthropods, its terrain adaptability was greatly reduced; and limited to the technological level at that time, no sensors were used for data collection, and the feedback adjustment ability for environmental changes was weak.

The hexapod robot Robot II, developed by the Bionic Robotics Laboratory of the School of Mechanical and Aerospace Engineering at Case Western Reserve University, has four independent degrees of freedom for each leg, three active degrees of freedom for rotation, and one passive degree of freedom along the axis of the tibia. Compliant degree of freedom, the potentiometer is used to measure the joint angular position, and the strain gauge is used to measure the axial force on the tibial joint, combined with the plantar reflex mechanism to cope with complex terrain. With more degrees of freedom on the legs, the ability to overcome obstacles has been greatly improved, and at the same time, great progress has been made in information collection for feedback regulation.

The hexapod robot Tarry II, developed by the School of Mechanical Engineering of the University of Duisburg in Germany, has three rotational degrees of freedom for each leg and is driven by a steering gear. It is equipped with a foot-end contact sensor and a two-axis accelerometer for measuring attitude. The strain measurement circuit installed in the femoral joint to obtain load information, and the ultrasonic sensor in the front of the torso for obstacle avoidance, can realize all-round walking on rough terrain. The shape, joints and foot design are slightly rough, and details such as anti-slip are not considered.

RHex, a hexapod robot developed by UC Berkeley and other units, has only one driver per leg, but realizes autonomy in power and control. At the same time, it is equipped with a three-axis accelerometer and a three-axis fiber optic gyroscope, which can adjust the posture after being disturbed by external forces, obtain the instantaneous posture of the trunk through the strain measurement unit of each leg, and quickly enable new autonomous gait control to reduce Drive the load to realize adaptive running. Its wheel-leg fusion idea provides a new idea for solving problems such as the slow speed of multi-legged robots.

Since the multi-joint mechanism has the advantages of large range of motion and good flexibility, it has been adopted by walking robots in recent years. However, the current articulated robot has the problems of complex structure and bulky body. For a hexapod walking robot to achieve omnidirectional walking, each leg needs to have at least three degrees of freedom. Because this structure is the closest to the limb structure of insects, it can achieve stable posture control and more flexible actions. The multi-degree-of-freedom leg design provides sufficient power for the walking robot and ensures the independence of movement; however, each additional degree of freedom requires an additional motor, which greatly increases the energy consumption of the movement.

Contents of the invention

The purpose of the utility model is to provide a multi-degree-of-freedom walking system for a hexapod robot, which has the characteristics of multi-degree-of-freedom, compact structure, good controllability, etc., and can help the hexapod robot adapt to unstructured environments.

The utility model comprises a first joint, a second joint, a third joint, a fourth joint, a fifth joint, an electronic cabin, a tibia and a foot; wherein the earring of the first joint is set on the second joint protruding at the upper end of the stator of the second joint on the platform, and fixed with several first screws; the earrings of the second joint are set on the boss of the third joint at the upper end of the stator casing 301 of the third joint, and fixed with the second screws; the third joint earrings on the rotor casing of the third joint The convex rib of the three joints is embedded in the groove of the fourth joint on the upper end of the fourth joint, and fixed with several third screws; the earrings of the fourth joint are set on the boss of the fifth joint of the fifth joint, and fixed with several third screws. Four screws are fixed; the fifth joint convex edge on the fifth joint is embedded in the electronic cabin groove at the upper end of the electronic cabin, and fixed with several fifth screws; the lower part of the electronic cabin is provided with a tibia, and the lower part of the tibia is provided with a foot.

The third joint includes a stator shell, a shell cover, a motor, a coupling, a drive shaft, a first bearing, a second bearing, a harmonic reducer, a dust cover, a spline shaft and a rotor shell, wherein the stator shell is set In the front section of the third joint, the upper end of the stator shell is provided with a boss of the third joint, the shell cover is provided with a first ear plate, the stator shell is provided with a second ear plate, and several first bolts pass through the first ear plate and the The second ear plate fixes the stator shell and the shell cover together, and tightens them with the first nut; there are several first through holes inside the stator shell, and several second through holes are opened on the base of the motor, and the second through holes are connected with the first through holes. One through hole corresponds to the other, the motor is put through the stator shell, the second bolt passes through the first through hole and the second through hole, and is tightened with the second nut to fix the motor and the stator shell together; the output end of the motor passes through the joint The drive shaft is connected with the transmission shaft, the transmission shaft, the first bearing, the harmonic reducer, the second bearing, the dust cover, the spline shaft and the rotor casing are threaded together coaxially in sequence, and the transmission shaft and the harmonic reducer Using the first key connection, the dust cover is fixed on the stator shell by the sixth screw to seal the second bearing; the rotor shell and the inner side of the second bearing have no clearance fit, and the outer side of the second bearing is interference fit with the stator shell; the spline shaft and Harmonic reducers are connected using the second key.

The internal structures of the first joint, the second joint and the fifth joint are completely the same as the internal structure of the third joint, so details are not repeated here.

Working principle and working process of the utility model:

The working principle of the third joint is that the motor output power in the stator shell is transmitted to the transmission shaft through the coupling, and then transmitted to the spline shaft through the deceleration and torque increase of the harmonic reducer, and then through the spline groove in the rotor shell Drive the rotor shell to rotate; through the control system in the electronic cabin, control the motor to run according to a certain law, so that when the stator shell is at rest, the rotor shell will make a rotary motion according to the given command.

The working principle of the first joint, the second joint and the fifth joint is exactly the same as that of the third joint, so it will not be repeated here.

The application process of the present utility model is as follows:

When the foot touches the ground, the ground information is transmitted to the electronic cabin through the pressure sensor, and the electronic cabin 6 judges and analyzes the terrain and adjusts the gait:

1. When touching flat terrain, the third joint and the fifth joint rotate to tighten the legs and reduce the span of the legs. After the first joint, the third joint, the fourth joint and the fifth joint are locked, at the same time the second joint The joints rotate to achieve small leg swings, adapting to flat terrain while saving energy.

2. When touching rough terrain, the third joint and the fifth joint rotate to stretch the legs and increase the span of the legs. After the first joint, the third joint, the fourth joint and the fifth joint are locked, at the same time the second joint Rotate to achieve a large leg swing and enhance the ability to avoid obstacles.

3. When touching the slope terrain, there is a large height difference between the left and right feet, and the third and fifth joints of the feet on the relatively higher side rotate to tighten the legs and reduce the span of the legs. After the first joint and the fifth joint The three joints, the fourth joint and the fifth joint are locked, and the second joint rotates at the same time; the third joint and the fifth joint of the foot on the relatively lower side rotate to stretch the leg and increase the span of the leg. After the first joint, The third joint, the fourth joint and the fifth joint are locked, and the second joint is rotated at the same time. Through the adjustment of the leg span between the left and right legs, the body of the hexapod robot is kept horizontal and suitable for slope terrain.

4. When the hexapod robot needs to walk laterally, the first joint and the second joint are locked, and at the same time the third joint and the fifth joint rotate to realize horizontal walking on the ground.

The beneficial effects of the utility model:

1. By converting the four-degree-of-freedom cooperation method, the adaptability of the robot to complex terrain such as slopes, narrow roads, ditches, and ridges can be improved, making the movement flexible and reducing energy consumption;

2. A harmonic reducer is installed inside the joint, and the reduction ratio is large and accurate, which reduces the design difficulty of the robot control system;

3. The noise is low, the transmission is stable, and the titanium alloy material is used to reduce the weight, save energy, improve the load capacity, small size and light weight, which is convenient to realize the light weight of the mechanism;

4. The electronic cabin of the leg can be equipped with an information collection system or a local control system of the leg, which reduces the complexity of the overall control system of the robot;

5. The parts have high adaptability, which is convenient for parts repair and replacement, and reduces the difficulty of maintenance.

Description of drawings

Fig. 1 is an overall three-dimensional schematic diagram of an embodiment of the utility model.

Fig. 2 is a three-dimensional exploded schematic view of the third joint of the embodiment of the present invention.

Fig. 3 is a schematic diagram of the internal structure of the third joint of the embodiment of the utility model.

Fig. 4 is a sectional view of the third joint of the embodiment of the present invention.

Fig. 5 is a three-dimensional schematic view of the first joint of the embodiment of the utility model.

Fig. 6 is a three-dimensional schematic view of the second joint of the embodiment of the present invention.

Fig. 7 is a three-dimensional schematic diagram of the third joint of the embodiment of the utility model.

Fig. 8 is a three-dimensional schematic diagram of the fourth joint of the embodiment of the utility model.

Fig. 9 is a perspective view of the fifth joint of the embodiment of the utility model.

Fig. 10 is a schematic diagram of the connection between the third joint and the fourth joint according to the embodiment of the present invention.

Fig. 11 is a schematic diagram of the connection between the fifth joint and the electronic cabin according to the embodiment of the present invention.

Among them: 1-first joint, 2-second joint, 3-third joint, 4-fourth joint, 5-fifth joint, 6-electronic cabin, 7-tibia, 8-foot, 9-third joint One screw, 10-the second screw, 101-the first joint earring, 11-the third screw, 12-the fourth screw, 13-the fifth screw, 201-the second joint earring, 202-the second joint boss, 301 -stator shell, 302-shell cover, 303-first bolt, 304-first nut, 305-first ear plate, 306-second ear plate, 307-first through hole, 308-motor, 309-second Bolt, 311-second through hole, 312-coupling, 313-transmission shaft, 314-first key, 315-first bearing, 316-second bearing, 317-harmonic reducer, 318-dust cover , 319-Third through hole, 320-Seventh screw, 321-Spline shaft, 322-Rotor shell, 323-Second key, 324-Third joint boss, 325-Third joint rib, 401-No. Four-joint earrings, 402-the groove of the fourth joint, 501-the convex platform of the fifth joint, 502-the convex edge of the fifth joint, 601-the groove of the electronic cabin.

Detailed ways

Please refer to Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7, Fig. 8, Fig. 9, Fig. 10 and Fig. 11, which are embodiments of the present utility model, which include the first joint 1. The second joint 2, the third joint 3, the fourth joint 4, the fifth joint 5, the electronic cabin 6, the tibia 7 and the foot 8; where the first joint earring 101 is set on the second joint 2 at the upper end of the stator The second joint boss 202 is fixed with four first screws 9; the second joint earring 201 is set on the third joint boss 324 at the upper end of the stator casing 301 of the third joint 3 and fixed with the second screw 10; The third joint rib 325 on the rotor casing 322 of the third joint 3 is inserted into the fourth joint groove 402 on the upper end of the fourth joint 4 and fixed with four third screws 11; the fourth joint earring 401 is sleeved on the fourth joint 4 The fifth joint boss 501 of the fifth joint 5 is fixed with four fourth screws 12; the fifth joint rib 502 on the fifth joint 5 is embedded in the electronic cabin groove 601 at the upper end of the electronic cabin 6, and fixed with four fourth screws 12; A fifth screw 13 is fixed; the lower part of the electronic cabin 6 is provided with a tibia 7, and the lower part of the tibia 7 is provided with a foot 8.

The third joint 3 includes a stator housing 301, a housing cover 302, a motor 308, a coupling 312, a drive shaft 313, a first bearing 315, a second bearing 316, a harmonic reducer 317, a dust cover 318, a flower The key shaft 321 and the rotor housing 322, wherein the stator housing 301 is arranged at the front section of the third joint 3, the upper end of the stator housing 301 is provided with a third joint boss 324, the housing cover 302 is provided with a first ear plate 305, and the stator housing 301 is provided with A second ear plate 306 is provided, and four first bolts 303 pass through the first ear plate 305 and the second ear plate 306 to fix the stator shell 301 and the case cover 302 together, and tighten them with the first nut 304; the stator shell 301 There are four first through-holes 307 inside, four second through-holes 311 are opened on the base of the motor 308, the second through-holes 311 correspond to the first through-holes 307, the motor 308 is put through the stator housing 301, The second bolt 309 passes through the first through hole 307 and the second through hole 311, and is tightened with the second nut 310, and the motor 308 and the stator housing 301 are fixed together; connection, the drive shaft 313, the first bearing 315, the harmonic reducer 317, the second bearing 316, the dust cover 318, the spline shaft 321 and the rotor housing 322 are coaxially threaded together in sequence, and the drive shaft 313 and the harmonic reducer The first key 314 is used to connect the rotors 317, the dust cover 318 is fixed on the stator housing 301 by the sixth screw 320, and the second bearing 316 is closed; The outer side is in interference fit with the stator housing 301 ; the spline shaft 321 and the harmonic reducer 317 are connected by a second key 323 .

The internal structures of the first joint 1 , the second joint 2 and the fifth joint 5 are completely the same as the internal structure of the third joint 3 , so details are not repeated here.

Working principle and working process of the present embodiment:

The working principle of the third joint 3 is that the motor 308 in the stator housing 301 outputs power, which is transmitted to the transmission shaft 313 through the coupling 312, and then transmitted to the spline shaft 321 through the deceleration and torque increase of the harmonic reducer 317, The spline groove in the rotor housing 322 drives the rotor housing 322 to rotate again; through the control system in the electronic cabin 6, the motor 308 is controlled to run according to a certain law, so that when the stator housing 301 is at rest, the rotor housing 322 performs a rotary motion according to a given command.

The working principles of the first joint 1 , the second joint 2 and the fifth joint 5 are exactly the same as those of the third joint 3 , so details will not be repeated here.

The application process of this embodiment is as follows:

When the foot 8 touches the ground, the ground information is transmitted to the electronic cabin 6 through the pressure sensor, and the electronic cabin 6 judges and analyzes the terrain and adjusts the gait:

1. When touching flat terrain, the third joint 3 and the fifth joint 5 rotate to tighten the legs and reduce the span of the legs. After the first joint 1, the third joint 3, the fourth joint 4 and the fifth joint 5 Locked, while the second joint 2 rotates to achieve small leg swings, adapting to flat terrain and saving energy.

2. When touching rough terrain, the third joint 3 and the fifth joint 5 rotate to stretch the legs and increase the span of the legs. After the first joint 1, the third joint 3, the fourth joint 4 and the fifth joint 5 lock At the same time, the second joint 2 rotates to achieve a large leg swing and enhance the ability to avoid obstacles.

3. When touching the slope terrain, there is a large height difference between the left and right feet, and the third joint 3 and the fifth joint 5 of the foot on the relatively higher side rotate to tighten the legs and reduce the span of the first joint after the legs 1. The third joint 3, the fourth joint 4 and the fifth joint 5 are locked, while the second joint 2 rotates; the third joint 3 and the fifth joint 5 on the relatively lower side of the foot rotate to extend the legs and increase the After the thigh span, the first joint 1, the third joint 3, the fourth joint 4, and the fifth joint 5 are locked, while the second joint 2 is rotated. By adjusting the leg span between the left and right legs, the body of the hexapod robot Keep level and apply to slope terrain.

4. When the hexapod robot needs to walk laterally, the first joint 1 and the second joint 2 are locked, and at the same time, the third joint 3 and the fifth joint 5 rotate to realize horizontal walking on a horizontal ground.

Claims (1)

1. A multi-degree-of-freedom walking system for a hexapod robot, comprising a first joint (1), a second joint (2), a third joint (3), a fourth joint (4), a fifth joint (5 ), electronic cabin (6), tibia (7) and foot (8), it is characterized in that: the first joint earring (101) is enclosed within the second joint boss (202) of the second joint (2) stator upper end and fixed with several first screws (9); the second joint earring (201) is set on the third joint boss (324) on the upper end of the stator casing (301) of the third joint (3), and fixed with the second joint Two screws (10) are fixed; the third joint rib (325) on the rotor casing (322) of the third joint (3) is embedded in the fourth joint groove (402) on the upper end of the fourth joint (4), and Several third screws (11) are fixed; the fourth joint earrings (401) are sleeved on the fifth joint boss (501) of the fifth joint (5), and are fixed with several fourth screws (12); The fifth joint convex rib (502) on the five joints (5) is embedded in the electronic compartment groove (601) on the upper end of the electronic compartment (6), and fixed with several fifth screws (13); the electronic compartment (6) The lower part is provided with a tibia (7), and the lower part of the tibia (7) is provided with a foot (8); The third joint (3) includes a stator housing (301), a housing cover (302), a motor (308), a shaft coupling (312), a drive shaft (313), a first bearing (315), a second bearing (316), harmonic reducer (317), dust cover (318), spline shaft (321) and rotor casing (322), wherein the stator casing (301) is arranged at the front section of the third joint (3), and the stator The upper end of the shell (301) is provided with a third joint boss (324), the shell cover (302) is provided with a first ear plate (305), and the stator shell (301) is provided with a second ear plate (306). The first bolt (303) passes through the first ear plate (305) and the second ear plate (306) to fix the stator shell (301) and the case cover (302) together, and tighten it with the first nut (304); the stator shell The inside of (301) is provided with several first through holes (307), offers several second through holes (311) on the base of motor (308), and the second through holes (311) and the first through holes (307) to Correspondingly, the motor (308) is put through the stator shell (30), the second bolt (309) passes through the first through hole (307) and the second through hole (311), and is tightened with the second nut (310), and the The motor (308) and the stator housing (301) are fixed together; the output end of the motor (308) is connected with the transmission shaft (313) through a shaft coupling (312), the transmission shaft (313), the first bearing (315), the harmonic The wave reducer (317), the second bearing (316), the dust cover (318), the spline shaft (321) and the rotor casing (322) are threaded together coaxially in sequence, and the transmission shaft (313) and the harmonic deceleration The first key (314) is used to connect the devices (317), the dust cover (318) is fixed on the stator casing (301) by the sixth screw (320), and the second bearing (316) is closed; the rotor casing (322) There is no clearance fit with the inner side of the second bearing (316), and the outer side of the second bearing (316) is interference fit with the stator housing (301); the second key ( 323) connect; The internal structure of the first joint (1), the second joint (2) and the fifth joint (5) is completely the same as that of the third joint (3).