261 results about "Robot leg" patented technology

A humanoid robot leg that may include a shank, an ankle that includes an ankle joint that is configured to perform yaw and pitch rotations, a knee joint, multiple ankle related (AR) rotational motors that are in mechanical communication, via multiple AR transmission mechanisms, with the ankle joint, and a knee related (KR) rotational motor that is in mechanical communication, via a KR transmission mechanism, with the knee joint. The multiple AR rotational motors and the KR rotational motor are positioned above the knee joint.

The invention discloses a covariance self-adaptive control method for a quadruped robot for spine joint adjustment. The method comprises the following steps that 1, a spine quadruped robot kinematics model with spine joints, a robot trunk dynamics model with the spine joints and a robot leg multi-rigid-body dynamics model are established; 2, based on the energy stability margin theorem and the spine joint coupling effect, a posture control method of the spine joint quadruped robot is provided by combining a covariance self-adaptive evolutionary strategy, and the angle, rigidity and damping coefficient of spine joints are estimated and adjusted according to the terrain gradient; 3, extracting the spatial relationship between the trunk mass center and the foot ends of the robot as an expected reference, updating the expected mass center position in real time, and constructing a model prediction control method to control the posture of the spinal joint quadruped robot; 4, the position of the foot falling point of the swing leg is designed in advance in combination with the additional freedom degree provided by the spine joint and MPC prediction state information. The motion stability of the robot in the complex terrain is improved.

The invention belongs to the technical field of link mechanism design algorithms, and particularly relates to a humanoid robot leg four-link mechanism design optimization method which comprises the following steps: simplifying a leg mechanical structure, and abstracting a mathematical model of a four-link mechanism; establishing a kinematic model of rotation of the four-bar mechanism, and calculating a rotation angle; analyzing kinematic characteristics of the four-bar mechanism in the rotating process; and establishing alternative schemes based on different combinations of the design parameters, and screening an optimal design scheme according to constraint conditions and dynamic characteristics. According to the method, a mathematical model for solving unique design parameters is not established, but a semi-empirical method is adopted, and an optimized design scheme is screened out by traversing possible combinations and analyzing dynamic characteristics one by one. According to the method, the multi-parameter model is established based on the four-connecting-rod mechanism, an optimization scheme is screened in combination with experience, the difficulty of establishing a complex model is reduced, the efficiency is improved through establishment of a unified design process, and the universality of the method is improved through introduction of manual analysis.

Disclosed in the present invention is a local terrain perception method for a legged robot, comprising the following steps: S1, providing on a legged robot at least one LiDAR, acquiring extrinsic parameters of the LiDAR with respect to a legged robot body coordinate system, and transforming to the legged robot body coordinate system point clouds scanned by the LiDAR; S2, removing motion distortion from the point clouds, transforming same to a legged robot gravity coordinate system, and keeping the point clouds within a set range; S3, reducing the dimensionality of the point clouds to a height information matrix; S4, performing hole filling on the basis of the height information matrix; S5, on the basis of the height information matrix, removing the effect of a leg point cloud of the legged robot on the height information matrix; and S6, analyzing the processed height information matrix, and computing a slope information matrix and an obstacle information matrix for the legged robot to plan footholds and avoid obstacles. The present invention has a low degree of dependency on high-precision odometers, and can directly observe terrains beneath and around legged robot bodies, allowing for more accurate perception.

The present application relates to the field of robot technology, and discloses a robot leg yaw joint support structure, a robot leg structure, a robot and a humanoid robot, wherein the robot leg yaw joint support structure mainly includes a leg roll output connector, a bearing and a leg yaw joint module. The connecting flange on the docking portion of the leg roll output connector is assembled and connected with the output flange of the leg yaw joint module, and a bearing for supporting is arranged between the docking portion and the output end of the leg yaw joint module. This arrangement forms a support system between the docking portion and the leg yaw joint module, and the output flange of the leg yaw joint module also forms a support system in the reducer section inside, thereby preventing the output flange of the leg yaw joint module from being biased, thereby protecting the reducer of the yaw joint module.

The invention relates to the technical field of humanoid robots, and particularly discloses a robot leg mechanism which comprises thighs, shanks, feet, adjusting driving parts and transmission parts. Wherein the shank is rotationally connected with the thigh, and a transmission channel is formed in the shank; the feet are rotationally connected to one ends of the shanks away from the thighs; the adjusting driving piece is arranged in the transmission channel; the transmission part penetrates through the transmission channel and extends in the same direction as the shank, one end of the transmission part is in transmission connection with the output end of the adjusting driving part, the other end of the transmission part is rotationally connected with the foot, and the adjusting driving part drives the transmission part to move so as to drive the foot and the shank to rotate relatively. According to the arrangement, the number of parts is greatly reduced, the assembling procedure is saved, and the assembling efficiency is improved; meanwhile, as the robot needs to serve as a supporting structure, the structural strength is large, the transmission part is arranged in the transmission channel, even if the robot falls down, the shanks cannot deform, and the possibility that the transmission part in the robot is bent is effectively reduced.

The invention relates to the technical field of foot type robot control, and provides a robot ground touching force estimation method and system based on a high-order finite time observer, and the method comprises the steps: building a foot type robot leg dynamic model; joint positions, speeds and joint acceleration driving items are selected as state variables, and a leg state space model of the legged robot is established; according to the established state space model, step-by-step iteration of an estimated value of a state variable is utilized, a power form of a nonlinear sign function and a set gain parameter matrix are combined, a high-order finite time observer is established in a recursive mode, and estimation of the ground touching force of the foot end of the foot type robot is obtained. A high-order finite time observer is established in combination with a nonlinear sign function and a designed parameter matrix, so that a ground touching force estimation error can be converged to a certain boundary within finite time, and the problems that a traditional extended state observer is low in ground touching force estimation precision and only can estimate slowly-changing ground touching force are effectively solved.

The present invention discloses a novel closed-chain octapod robot, belonging to the field of closed-chain legged robots; it includes a frame, four walking leg assemblies, and a driving mechanism; the walking leg assembly includes a gear transmission mechanism, a deformable octapod leg mechanism, and several connecting pieces, the gear transmission mechanism includes a first gear set and a second gear set, the driving mechanism includes an adjustment servo installed on the walking leg assembly, and also includes a driving motor installed on the frame and a one-to-four belt transmission mechanism; the driving motor and the adjustment servo drive the octapod leg mechanism to swing back and forth, and the four groups of octapod leg mechanisms coordinate with each other to enable the octapod robot mechanism to perform walking actions. The present invention selects a closed-chain octapod structure as the walking mechanism of the legged robot. This solution has the advantages of few driving numbers, low energy consumption, large overall stiffness, and strong load capacity, and is an important research field for the innovation of the leg configuration of bionic robots.

The utility model provides a robot leg structure and a robot, and relates to the technical field of robots, the robot leg structure comprises a driver, a shear fork mechanism and a horizontal supporting platform, the driver is in driving connection with the control end of the shear fork mechanism, and the horizontal supporting platform is connected with the lifting end of the shear fork mechanism; the driver is used for driving the horizontal supporting platform to move in the vertical direction through the shear fork mechanism. Compared with a traditional multi-driver structure, lifting motion of the horizontal supporting platform can be achieved only through one driver, the number of the drivers and complexity of related control circuits are remarkably reduced, and therefore the manufacturing cost and debugging difficulty of the system are effectively reduced. Moreover, the shear fork mechanism can keep the horizontal state of the horizontal supporting platform in the whole lifting process, so that the posture of the upper body of the robot is more stable, and the operation precision or stability is prevented from being affected by inclination or shaking. In addition, due to the fact that the scissor fork mechanism and the driver are simple in structure, the maintenance requirement of the system is remarkably reduced.

A robot leg structure imitating tendon motion control comprises a thigh structure, a shank structure and a motion control assembly part, the bottom of the thigh structure is rotationally connected with the top of the shank structure through a knee joint structure, and a foot plate structure is rotationally installed at the bottom of the shank structure through an ankle joint structure; the motion control assembly part is arranged at the top of the thigh structure or above the thigh structure, the motion control assembly part is connected with at least one tendon-imitating driving stay wire structure, and the tendon-imitating driving stay wire structure is used for controlling and connecting the thigh structure, the shank structure and / or the foot plate structure. According to the robot, the dynamic performance, the naturalness and the flexibility are good, the joint load is small, the whole leg can be slender and exquisite, the stability of the joint structure is high, the needed initial driving force is small, therefore, the power consumption can be lower, and the robot has the long-time endurance walking capacity.

The invention discloses a hydraulic humanoid robot leg structure driven by a blade swing cylinder and a direct-drive valve bank, which comprises a thigh structure, a shank structure and a foot plate structure, the thigh structure is provided with a direct-drive multi-way valve bank, the end part of the thigh structure is provided with a hip joint blade swing cylinder actuator and a hip joint yaw shaft piston cylinder actuator, and the hip joint yaw shaft piston cylinder actuator is provided with a hip joint blade swing cylinder. A knee joint pitch shaft blade swing cylinder actuator is installed at the end of the shank structure, and a piston cylinder actuator is installed on the shank structure. By adopting the hydraulic driving scheme of combining the precise blade oscillating cylinder and the piston cylinder and concentrating the servo valve group on the outer side of the thigh, the defects of the existing technical schemes of speed reducer motor driving, lead screw electric cylinders, traditional hydraulic piston cylinders and the like in high-load, high-speed movement and long-term use are successfully overcome. The lower limb structure of the humanoid robot has the characteristics of high torque output, high-speed rotation, excellent heat dissipation and durability, low electromagnetic interference and the like, and provides higher flexibility, reliability and adaptability for the lower limb structure of the humanoid robot.

The utility model discloses a leg device of a foot type robot and the foot type robot. The leg device of the foot type robot comprises a robot leg and further comprises a driving motor arranged in the robot leg, the driving motor comprises a shell, a power cavity formed in the shell and a power assembly arranged in the power cavity, and a first containing cavity is formed in the end face of the tail of the shell; a motor controller electrically connected with the power assembly is arranged in the first containing cavity, and cooling fins are arranged on the motor controller and connected with the shell in a heat conduction mode. The utility model further discloses the foot type robot which adopts the leg device of the foot type robot. The motor controller has the advantage of solving the problem that the motor controller for installing the motor in the leg of the humanoid robot is easy to overheat. The cooling fins are connected with the shell in a heat conduction mode, heat generated by the motor controller can be rapidly transmitted to the shell and then dissipated to the surrounding environment through the shell, faults caused by overheating of the motor controller are avoided, and stable operation of the motor controller is guaranteed.

The invention discloses a leg motion control method and system for a flying type double-wheel-leg robot based on active-disturbance-rejection control, and the method comprises the following steps: S1, solving a five-connecting-rod kinematics calculation formula of the legs of the robot based on the geometrical relationship of a five-connecting-rod mechanism; s2, on the basis of the five-connecting-rod kinematics solution formula, virtual model control is utilized, and the mapping relation between the force of the working space and the joint torque is obtained; s3, solving a kinetic equation of a leg mechanism of the robot by utilizing a Lagrange equation; s4, constructing an active-disturbance-rejection control model based on the kinetic equation, and dynamically optimizing the active-disturbance-rejection control model by using an RBF neural network to obtain a robot leg control model; and S5, regulating and controlling the leg movement of the robot by using the robot leg control model.

The utility model discloses a leg structure of a biped robot and a humanoid robot. The biped robot leg structure comprises a hip joint assembly, a thigh assembly, a shank assembly and a foot which are connected in sequence. The hip joint driving motor is connected with the knee joint driving motor through a connecting assembly, and the hip joint driving motor and the knee joint driving motor are coaxially arranged; the shank assembly and the thigh assembly are connected through a first ankle joint rotating motor, and the first ankle joint rotating motor serves as a knee joint rotating shaft. The first ankle joint rotating motor is located at the root of the shank assembly, and the knee joint driving motor is located at the root of the thigh assembly so as to reduce inertia of the tail ends of robot limbs. The leg structure of the biped robot is improved, inertia is made to move upwards by moving the driving motor upwards, and the flexibility and the dynamic performance of the robot are improved; the compactness of the leg structure of the biped humanoid robot is improved, the transmission angle is effectively limited, the transmission stability is improved, and the encoder and the like are convenient to maintain.

The utility model discloses a leg parallel structure of a bionic wheel-foot robot, which comprises a machine body, a support, motors and wheel feet, and is characterized in that a plurality of first motors are fixedly connected onto the machine body, spacing frames are fixedly connected onto rotating shafts of the first motors, and second motors are fixedly connected onto the spacing frames through bolts; a first support is fixedly connected to a rotating shaft of the second motor and rotationally connected with a second support through a bearing. The robot has the advantages that the occupied space is small, the layout between the two execution motors is compact, the number of structural parts is reduced, the requirement for light weight is met under the condition that the strength is not changed, and the two motors are controlled respectively and matched with each other to achieve robot control.

The invention discloses a leg joint structure of a foot type robot. The leg joint structure comprises a motor assembly, a thigh shell, a connecting rod transmission assembly, a shank and a foot end. The motor assembly drives the shank to rotate relative to the thigh through the connecting rod transmission assembly. In the connecting rod transmission assembly, a speed reduction connecting rod is introduced between a driving crank and a thigh connecting rod, so that the transmission angle of the driving crank and a next-stage connecting rod is larger, and a motor can drive a shank to move with smaller torque; by designing equal-length speed reduction connecting rods at the two ends of the thigh connecting rod, the transmission angles of a driving crank and a next-stage connecting rod as well as a driven crank and an upper-stage connecting rod in the movement process are improved; and meanwhile, two pairs of parallel pin roller structures are mounted on a thigh shell to limit a thigh connecting rod to only do translational motion, so that the leg joint structure provided by the invention has a larger space movement range before a driving crank and a driven crank reach a dead point position compared with a leg joint without introducing a speed reducing connecting rod and pin roller limiting.

The application relates to the technical field of robots, and discloses a robot leg walking mechanism and a quadruped robot, which comprise a plurality of large arms, one side of each large arm is connected with a floating assembly, the floating assembly comprises a connecting box and an air bag, the connecting box is fixedly connected with one side of the large arm, a placing groove is formed in the side of the connecting box away from the large arm, and the air bag is fixedly connected in the placing groove; the large arm is sequentially connected with an air charging assembly, an air discharging assembly and a jetting assembly from top to bottom on one side; and the connecting box is connected with a closing assembly on one side. The robot leg walking mechanism and the quadruped robot utilize the floating assembly, the quadruped robot can float in a deep water area, the body is prevented from being completely immersed in water, the risk that a camera lens is splashed with water is reduced, the quality and accuracy of real-time image transmission are ensured, a clear field of vision and stable walking ability are provided for the quadruped robot, visual misjudgment or distortion is reduced, and the accuracy and efficiency of a patrol task are improved.

The low-inertia small robot leg structure comprises a first connecting piece, a second connecting piece and a shank, the first connecting piece is provided with a first joint motor, the first joint motor is connected with the second connecting piece, and the axis of the first joint motor is perpendicular to the axis of the second connecting piece; a second joint motor is arranged on the second connecting piece, and a thigh clamping plate is connected to the second joint motor; a third joint motor is arranged between the thigh clamping plates, the shanks are rotationally arranged between the bottoms of the thigh outer clamping plates and the thigh inner clamping plates to form knee joints, and connecting rods are rotationally connected between the positions, lower than the knee joints, of the shanks and the third joint motor. According to the leg compact structure design suitable for the small robot, the number of transmission mechanisms at the knee joints is reduced, the rotational inertia of the legs of the robot is reduced, the energy consumption intensity is reduced under the condition that the battery energy of the small robot is low, and the standby time of the small robot is prolonged.

The invention belongs to the related technical field of robots, and discloses a robot leg structure and a biped robot, a hip joint module in the leg structure comprises a side extension driving module, a turnover driving module and a pitching driving module, one ends of the three modules are installed on a hip joint installation frame in a series connection mode, and the other ends of the three modules are connected with thighs; the knee joint module is located in the containing cavity of the thigh part, the knee joint module comprises a linear driving module, the fixed end of the linear driving module is rotationally connected with the upper portion of the thigh part, the movable end of the linear driving module is in transmission connection with the top of the shank part, and the linear driving module drives the shank part to do pitching motion through linear telescopic movement; the bottom of the shank part is hinged to the foot bottom part through a cross shaft structure, and the ankle joint module is arranged on the shank part and is in transmission connection with the foot bottom part so as to complete pitching and side stretching movement. The design of hybrid driving of the linear and rotary joint modules gives consideration to the requirements of high robustness and low energy consumption of the foot-type robot in a real scene.

The invention provides a wheel-legged quadruped robot state estimation method and system, and the method comprises the steps: obtaining the stress information of four wheels of a wheel-legged robot, IMU information, and the joint angle and joint angular velocity of each robot leg joint through a six-dimensional force sensor, an IMU and a joint encoder; and then calculating the position and speed information of the foot end points of the four-foot wheel-leg robot in swinging or underground touching and the speed of the wheels. According to the IMU information, the acceleration of the four-foot wheel-leg robot is calculated, the current position and speed of a robot body are predicted according to the optimal estimated value, obtained through previous prediction, of the state of the robot body, and prediction data are obtained. And through extended Kalman filtering, fusing the calculated position and speed information of the foot end point when the foot end point swings or touches the ground and the speed of the wheel with the prediction data to obtain an optimal estimation value of the current body state of the robot.

A rigid-flexible coupled leg structure of a biped robot comprises a trunk module, a hip joint module, a thigh module, a shank module and a foot module which are sequentially connected from top to bottom. Shock absorbers are connected between the thigh module and the shank module and between the shank module and the foot module. The compact design of the leg structure is realized through the series layout of the motor and the reasonable integration of key parts; meanwhile, a four-connecting-rod driving mechanism is introduced, so that the joint torque transmission efficiency and the overall movement performance are improved; and on the premise of ensuring the light weight of the system, the stability and response capability of the robot in dynamic actions such as walking and take-off are effectively enhanced.

The invention discloses a hexapod robot leg and arm multiplexing control method and device based on reinforcement learning, and relates to the field of motion control. The method comprises the following steps: acquiring observation information of a target hexapod robot; inputting the observation information into the control strategy model to obtain an expected joint angle of the target hexapod robot; the control strategy model is obtained by performing strategy updating on a training framework based on a value network by adopting a reinforcement learning method according to a constructed multi-task training environment; the training architecture is determined based on privilege learning of teachers and students; the value network comprises a shared feature layer and a multi-task head which are connected in sequence; the training architecture comprises a state estimation encoder, a topographic information encoder, a privilege information encoder, a historical information encoder and an ontology network; and a PD control method is adopted to determine the joint torque based on the expected joint angle so as to control leg-arm multiplexing of the target hexapod robot. According to the invention, leg and arm multiplexing control of the hexapod robot can be realized.

A robot leg based on tendon-imitating motion control comprises a thigh structure, a shank structure and a motion control assembly part, the bottom of the thigh structure is rotationally connected with the top of the shank structure through a knee joint structure, and a foot plate structure is rotationally installed at the bottom of the shank structure through an ankle joint structure; the motion control assembly part is arranged at the top of the thigh structure or above the thigh structure, the motion control assembly part is connected with at least one imitated tendon driving pull wire assembly, and the imitated tendon driving pull wire assembly is used for controlling and connecting the thigh structure, the shank structure and / or the foot plate structure. According to the robot, the dynamic performance, the naturalness and the flexibility are good, far-end driving can be achieved, the whole legs can be slender and exquisite, the joint load is small, so that the rotational inertia is small, the joint structure stability is high, the needed initial driving force is small, the power consumption is lower, and the robot has the long-time endurance walking capacity.

The invention discloses a rigid-flexible coupled walking robot leg mechanism and a walking robot. The walking robot is provided with a walking robot leg mechanism, and the walking robot leg mechanism comprises a shank driving motor (4) and a shank driving connecting rod (7); the shank driving motor is assembled and connected with a thigh component (6), a crank connecting piece (5) is installed at the driving end of the shank driving motor and provided with a crank end (51), one end of the shank driving connecting rod is assembled and connected with the crank end, and the other end of the shank driving connecting rod is assembled and connected with the portion, close to the upper end, of a shank component (8) through a rotating pair. The shank driving connecting rod is an elastic connecting rod. The shank driving connecting rod serves as a structural part to transmit motion and also serves as an elastic component to play a role of an elastic plate spring, external loads are buffered through structural elastic deformation, the structural characteristics of bones, muscles and ligaments of an organism can be simulated, and a leg mechanism has good passive compliance.

The invention discloses a flexible robot foot end device capable of detecting multi-dimensional contact force, and relates to the technical field of foot type robots. The sensor comprises a mounting shell, a hemispherical flexible protective sleeve, a pressed block, a spring, a Hall circuit board, a buffer sponge, a magnetic mechanism and a flexible constraint film, the mounting shell is fixedly connected with legs of the foot type robot, and the lower end of the mounting shell is fixedly connected with the Hall circuit board and the upper end of the spring. Through the unique combination of the pressed block, the magnetic mechanism and the Hall circuit board, the component of the contact force in a three-dimensional space can be accurately solved, the limitation of the detection dimension of a traditional foot end device is broken through, the robot can more accurately sense the environment in complex terrains and tasks, the accuracy and stability of motion control are improved, and the robot is more suitable for popularization and application. Powerful support is provided for efficient operation of the robot in a complex environment, the flexible protective sleeve and the buffer sponge effectively absorb impact energy, and internal elements are prevented from being damaged due to rigid collision.

The application discloses a robot leg structure and a control method thereof. The structure comprises a hip joint module, a thigh module, a knee joint module, a shank module and a foot end module. A flat plate stopper is arranged on a structure connecting surface of each of the hip joint module, the thigh module, the knee joint module, the shank module and the foot end module, and the modules are connected based on the flat plate stopper. The hip joint module comprises a first driving unit, a second driving unit and a third driving unit. The first driving unit controls a roll freedom degree, the second driving unit controls a pitch freedom degree, and the third driving unit controls a yaw freedom degree. Driving axes of the first driving unit, the second driving unit and the third driving unit are perpendicular to each other and intersect at the same point. The knee joint module is driven based on a torque motor. A rotor of the torque motor is connected with the thigh module, and a stator of the torque motor is connected with the shank module. The robot leg structure has the advantages of improving motion stability, enhancing joint control precision and optimizing dynamic response capability.

The utility model discloses a robot foot sole, a robot leg and a robot. The foot sole comprises a foot sole supporting piece, a foot sole mounting piece and an elastic piece. The plantar supporting piece comprises a plantar supporting outer surface far away from one side of the robot and a plantar supporting inner surface close to one side of the robot, and a plantar supporting mounting part is arranged on the plantar supporting inner surface; the plantar mounting piece is detachably connected with the plantar supporting mounting part; the elastic piece is arranged in the sole supporting piece; the foot sole mounting piece is detachably connected with the foot sole supporting mounting part, so that the foot sole supporting piece is convenient to disassemble and assemble, the operation time is greatly shortened, and the maintenance efficiency is greatly improved; the elastic piece is arranged in the sole supporting piece, the mechanical damping function is achieved, the sole supporting piece can be made of a hard material, then the abrasion resistance of the sole supporting piece is improved, meanwhile, it is guaranteed that the sole has the good buffering performance through the arrangement of the elastic piece, and the selection contradiction problem of damping performance and durability in a traditional structure is solved.

The invention discloses a robot leg transmission structure with a flexible joint, a common rigid joint and a flexible link. The robot leg transmission structure mainly comprises a motor module, a connecting rod transmission module and a sole module. The motor module is composed of two motor joint modules with the flexible torque measuring function, a rigid joint module and a motor connecting piece, and multi-axis cooperative driving is achieved. The connecting rod transmission module is of a parallel four-rod structure, a driving crank is connected with the output end of a rigid joint, a flexible crank structure formed by compounding aluminum alloy and a rubber layer is adopted, and good buffering capacity and dynamic response performance are achieved. The sole module is of a multi-cavity air chamber structure and comprises a conical hole used for absorbing high-frequency vibration, a main air chamber used for absorbing low-frequency impact and a supporting column structure used for preventing collapse, a force sensor is arranged on the top, and real-time force sensing of the foot end is achieved. The transmission configuration has excellent impact resistance, structural flexibility and sensing integration, and is suitable for robot platforms in various complex terrains and dynamic task environments.

This invention discloses a damped adjustable robot leg system and its control method. The leg system includes a thigh, a lower leg, a link, an adjustable damper, wheel feet, and a wheel-side motor. One end of the thigh is hinged to one end of the lower leg, while the lower leg is hinged to the other end of the thigh via a link, forming a parallelogram mechanism. The wheel feet are located at the other end of the lower leg, and the wheel-side motor is fixed to the side of the wheel feet to drive their movement. The adjustable damper is fixed between the wheel-side motor and the other end of the lower leg. The adjustable damper can adjust the damping of the leg system. When the adjustable damper is locked, the leg system is in a fully rigid state. This invention not only increases the robot's obstacle-crossing ability when walking on wheels, but also reduces the vibration of walking on bumpy roads and reduces damage to the joint motors.