Ubtech Robotics Corp Ltd

Yuesong Wang

Youjun Xiong

Mingguo Zhao

Xiaoyu Ren

Liqun Huang

Xiaozhu Ju

Hao Dong

A total centroid state estimation method as well as a humanoid robot and a computer readable storage medium using the same are provided. The method includes: obtaining a motion state of each real joint of the humanoid robot and a motion state of its floating base, where the floating base is equivalent to a plurality of sequent-connected virtual joints; calculating a joint position, a centroid position, and a rotation matrix of each link in the world coordinate system in sequence using the chain rule of homogeneous multiplication according to the position of the joint corresponding to the link to solve a Jacobian matrix of the centroid of the link; solving a total centroid Jacobian matrix based on the Jacobian matrix of the centroid of each link and the total mass; and calculating the total centroid velocity based on the total centroid Jacobian matrix and other parameters.

Total centroid state estimation method, humanoid robot and computer readable storage medium using the same

An inverse kinematics solving method for redundant robot as well as a redundant robot using the same are provided. The method includes: obtaining an expression of a Jacobian matrix null space of a current configuration of each robotic arm of the redundant robot corresponding to a preset end pose of the robotic arm according to the preset end pose, and obtaining a relation between an angular velocity of the joints of the redundant robot in the Jacobian matrix null space of the current configuration based on the obtained expression; traversing the Jacobian matrix null space using the relation, and building an energy cost function of the redundant robot based on the relation; obtaining a target joint angle of each joint of the redundant robot based on the optimal inverse kinematics solution to transmit to the servo of the joint so as to control the joint.

Inverse kinematics solving method for redundant robot and redundant robot and computer readable storage medium using the same

The present disclosure provides a robot posture control method as well as a robot and a computer readable storage medium using the same. The method includes: constructing a virtual model of the robot, wherein the virtual model comprises a momentum wheel inverted pendulum model of the robot and an angle between a sole surface of the robot and a horizontal plane; and performing a posture control based on outer-loop feedback control, inner loop compensation for the external disturbance rejection in position level, inner loop external disturbance rejection via null-space in velocity level, and inner loop external disturbance rejection in force/acceleration level on the robot. In this manner, a brand-new virtual model is provided, which can fully reflect the upper body posture, centroid, foot posture, and the like of the robot which are extremely critical elements for the balance and posture control of the robot.

Robot posture control method and robot and computer readable storage medium using the same

The present disclosure provides a robotic arm space position adjustment method, a robotic arm controller, and a computer readable storage medium. The method includes: calculating a potential energy function of moving a feature point of the robotic arm to a reference point based on an obtained preset acceleration of an artificial gravitational field, first vector of the artificial gravitational field in a preset reference coordinate system, second vector of the feature point of the robotic arm in the preset reference coordinate system, and a third vector of the reference point in the preset reference coordinate system; and calculating a null space virtual moment of moving the feature point of the robotic arm to the reference point based on a preset null space operator and the potential energy function, so as to adjust each joint of the robotic arm.

Robotic arm space position adjustment method, robotic arm controller and computer readable storage medium

The present disclosure provides a redundant robotic arm control method, a redundant robotic arm, and a computer readable storage medium. The method includes: obtaining an external force acting on an end of the robotic arm and an external torque acting on each joint; calculating a first joint speed of each joint based on a degree of influence of the joint on the end in each motion dimension and the external force acting on the end; determining a zero space speed of each joint corresponding to a current position of the end based on a link torque of an external force acting on a link with respect to the joint; calculating a total joint speed based on the first joint speed and the zero space speed; and controlling the robotic arm to the move according to the total joint speed.

Redundant robotic arm control method, redundant robotic arm controller, and computer readable storage medium

A feedforward control method comprising steps of: acquiring kinematic parameters of each joint of a robot based on inverse kinematics according to a pre-planned robot motion trajectory, and setting a center of a body of the robot as a floating base; determining a six-dimensional acceleration of a center of mass of each joint of the robot in a base coordinate system using a forward kinematics algorithm, based on the kinematic parameters of each joint of the robot, and converting the six-dimensional acceleration of the center of mass of each joint of the robot in the base coordinate system to a six-dimensional acceleration in a world coordinate system; and calculating a torque required by a motor of each joint of the robot using an inverse dynamic algorithm, and controlling the motors of corresponding joints of the robot.

Feedforward control method for floating base dynamics, computer-readable storage medium and robot

The present disclosure provides a robot centroid position adjustment method as well as an apparatus and a robot using the same. The method includes: obtaining initial values; obtaining a waist velocity adjustment value; calculating a current value of the centroid position; and determining whether a current value of the centroid position is equal to the planning value of the centroid position; if the current value of the centroid position is not equal to the planning value of the centroid position, obtaining the current value of the centroid position to take as the initial value of the centroid position and returning to the step of obtaining the waist velocity adjustment value until the current value of the centroid position is equal to the planning value of the centroid position. In such a manner, the balance ability of the robot can be improved.

Robot centroid position adjustment method and apparatus and robot using the same

The present disclosure provides an acceleration compensation method for a humanoid robot as well as an apparatus and a humanoid robot using the same. The method includes: calculating an angular acceleration of each joint and calculating a six-dimensional acceleration of a centroid of a connecting rod corresponding to the joint in an absolute world coordinate system, if the humanoid robot is in a single leg supporting state; calculating a torque required by the angular acceleration of each joint of the humanoid robot; determining a feedforward current value corresponding to the torque of each joint; and superimposing the feedforward current value on a control signal of each joint to control the humanoid robot. In this manner, the influence of the acceleration can be effectively suppressed, the rigidity of the PID controller of the humanoid robot can be reduced, thereby improving the stability of the entire humanoid robot.

Acceleration compensation method for humanoid robot and apparatus and humanoid robot using the same

A method for controlling walking of a robot includes: determining a stance of the robot, in response to the robot being in a single-leg stance, determining a rotational angle of each of the joints, and calculating a value of a torque produced by a force of gravity acting on the robot about each of the joints; in response to the robot being in a double-leg stance, calculating a position of a projection of a center of mass of the robot on a surface where the robot stands, and calculating a value of a torque produced by a force of gravity acting on the robot about each of the joints according to the position of the projection; obtaining a feed-forward current of each of the joints; and applying the feed-forward current of each of the joints to a corresponding actuator of this joints.

Method for controlling walking of robot and robot

The present disclosure provides a joint control method for a serial robot and a serial robot using the same. The method includes: performing a analysis on an end joint in the plurality of joints, and calculating the force of the previous joint acting on the end joint; performing a analysis on each of the other joints in the plurality of joints, and calculating the force of the previous joint acting on the joint; obtaining an angular velocity and an angular acceleration of each joint after obtaining the force of the previous joint acting on the joint, and calculating a torque corresponding to each joint; and projecting the torque corresponding to each joint to a motor corresponding to the joint to obtain a torque to be applied to the motor at a current time. In this manner, which improves the tracking precision of the end joint while reduces the tracking error.

Joint control method for serial robot and serial robot using the same

The present disclosure provides an impedance control method for a biped robot as well as an apparatus and a biped robot using the same. The method includes: correcting an impact force on a landing leg in the two legs of the biped robot using a natural attenuation function, and taking the corrected impact force as an input of an impedance control; obtaining an impedance model of the biped robot; determining a transfer function of the impedance control based on the impedance model; calculating an output of the impedance control based on the input of the impedance control and the transfer function of the impedance control; determining a joint angle of each joint based on the output of the impedance control and a planned pose of the biped robot; and transmitting joint angle information of each joint to motor(s) of the joint to perform the impedance control.

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Shenzhen, China

Yuesong Wang