11 results about "Joint variable" patented technology

The invention discloses a collaborative robot joint external force estimation method, and relates to the technical field of collaborative robot joint external force estimation, and the method comprises the steps: building a joint kinetic model, and obtaining the basic kinetic parameters of a collaborative robot joint; the angular displacement deviation between the input shaft and the output shaft of the speed reducer is obtained, and the compensated torsional angle difference is calculated according to the angular displacement deviation; a joint variable stiffness model is established, multiple sets of calibration data are obtained through experiments, and parameters in the joint variable stiffness model are identified according to the multiple sets of calibration data; based on the basic dynamic model and the joint variable stiffness model after parameter identification, a nonlinear disturbance observer is constructed in combination with introduced auxiliary variables; and system disturbance is observed and compensated through a nonlinear disturbance observer, so that an external torque estimated value acting on the tail end of the joint is calculated and output in real time. According to the method, high-precision and real-time estimation of the external torque can be effectively considered, and meanwhile, the system hardware cost and the structure complexity are greatly reduced.

The embodiment of the application provides a surgical robot control method, a surgical robot and a readable storage medium, the method comprises the following steps: acquiring a first joint variable of a first posture joint; based on the mapping between a first end effector and a first operating part, controlling the first posture joint according to the first joint variable, so that the posture of the first operating part is aligned with the posture of the first end effector; controlling the first operating part and the second operating part to change the position and / or the self-rotation posture of the target point according to the instruction of the operator; based on the mapping between the target point and the image device, controlling the image device to follow the position of the target point, and / or controlling the image device to be aligned with the self-rotation posture of the target point, so that when the first end effector is switched back to be controlled, the posture alignment does not need to be performed again, thereby improving the control experience.

The invention discloses a mechanical arm kinematics modeling and motion control method, device and system. The mechanical arm comprises N joints connected in series and a sand disc connected to the tail end, and a radial distance R exists between the working edge of the sand disc and the tail end arm section. The kinematics equation construction method comprises the following steps: determining a working edge reference point of a sand disc as a motion control target; based on mechanical structure parameters, joint variables and a radial distance R of the mechanical arm, forward and inverse solution equations of the kinematics position, speed and acceleration of a working edge reference point are deduced. The motion control method comprises the following steps: acquiring a discrete expected position, speed and acceleration point; calculating an expected joint angle, angular velocity and angular acceleration by using a position inverse solution equation, a velocity inverse solution equation and an acceleration inverse solution equation in sequence; and giving a calculation result to a multi-axis motion controller in real time. According to the method, the radial distance of the sand disc is incorporated into the kinematics model, feedforward control of three levels of position, speed and acceleration is achieved, and the motion control precision of the non-standard mechanical arm is remarkably improved.

The application relates to a kind of mechanical arm path planning methods based on way point, wherein, method includes: the joint variable value corresponding to each joint in target mechanical arm at current way point is calculated, and the distance between current way point and next way point is determined, and whether the distance is not greater than preset interval value is judged;If not greater than preset interval value, each joint motion instruction from current way point to next way point is written by joint motion equalization strategy, otherwise interpolation segmentation is carried out between current way point and next way point, and the interpolation direction corresponding to current way point is determined, and each joint motion instruction in each interpolation segment is written according to interpolation direction and joint motion equalization strategy;The corresponding action of target mechanical arm is controlled by each joint motion instruction. Thus, it solves the problem that the existing method causes unnecessary waste of energy in the movement process of mechanical arm, and the inverse solution calculation complexity is higher when having redundant degree of freedom, which affects the path planning efficiency of mechanical arm.

The invention provides a universal numerical control machine tool control method and system, and belongs to the field of machine tool numerical control systems and motion control. Performing exponential product modeling on each joint according to the joint type, the axis direction and the axis passing point, and obtaining a transformation relation of the tail end of the cutter side of the kinematic chain relative to a machine tool base standard system and a transformation relation of the tail end of the workpiece side relative to the machine tool base standard system; according to the kinematics relation, a kinematics equation about the position and the direction is created, and the position of the tool nose point in the workpiece coordinate system and the direction of the tool shaft in the workpiece coordinate system are related to the kinematics equation; and based on a kinematics equation, taking an error function of a tool nose point and a tool axis direction as a target function, and adopting a numerical optimization strategy to solve an optimal solution of each joint variable and control a numerical control machine tool to act. According to the invention, control of numerical control machine tools with various structures can be realized, and the adaptation capability and development efficiency of a numerical control system of the numerical control machine tool are improved.

The embodiment of the present application provides a method for calibrating kinematic parameters of a robot. The method comprises the following steps: acquiring a displacement pair, determining an error value for calibrating the kinematic parameters of the robot according to the displacement pair, and the displacement pair comprises an actual movement displacement and a nominal movement displacement. The actual movement displacement is determined by the size of a calibration object and the size of an image of the calibration object acquired by an executor of a robot end; and the nominal movement displacement is determined by a robot kinematic model and joint variables of the robot, and the posture of the robot end at a first position and a second position is the same. The actual movement displacement of the robot end is determined by the size of the calibration object and the size of the image acquired by the executor of the robot end, so that the calibration of the kinematic parameters of the robot can be realized under the premise of reducing the calibration cost.

The invention discloses a universal six-axis mechanical arm inverse kinematics solving method based on homotopy continuation, which comprises the following steps: acquiring a target pose of an end effector of a six-axis mechanical arm, and constructing a pose error equation about six joint variables based on the target pose and connecting rod parameters of the six-axis mechanical arm; constructing a homotopy equation based on the pose error equation and a preset auxiliary function; performing solution path tracking on the homotopy equation by adopting a numerical iteration method according to a preset change sequence of the homotopy parameters from a starting value to a stopping value, and sequentially substituting each value in the preset change sequence into the homotopy equation and solving to obtain a group of inverse kinematics solutions of the pose error equation; on the basis of a low-difference sequence sampling method, a plurality of groups of different initial joint variable values are generated in the six-dimensional joint space, the total group number of the initial joint variable values serves as the number of cycles, the iteration steps are repeatedly executed for each group of initial joint variable values, and multiple groups of different inverse kinematics solutions of the pose error equation are obtained.

The invention discloses a humanoid robot tumble protection and tumble recovery method based on a state triggering hybrid strategy, and the method comprises the steps: carrying out the training of tumble protection and standing recovery as two independent skill networks through staged training and a layered reinforcement learning architecture; and autonomous switching and smooth transition between the two are realized by a high-level state triggering strategy. The falling protection strategy network focuses on impact minimization and safe grounding, and collision damage is reduced through joint variable stiffness compliance control; and the falling recovery strategy network is combined with a reference trajectory generated by inverse kinematics based on skeleton binding and animation to realize natural and efficient standing actions. According to the method, mixed action space output is adopted, the joint torque peak value and the hardware damage risk are remarkably reduced while the behavior flexibility and certainty are guaranteed, and the recovery robustness and action anthropomorphism of the robot in an unknown environment are improved.

A kind of SSRMS mechanical arm inverse kinematics solving method based on arm type angle parameterization relates to space mechanical arm control technical field.Joint bias structure parameter is introduced, and the kinematics model of mechanical arm is established;SSRMS mechanical arm is based on the inverse kinematics analytical solution of joint angle parameterization;The definition and solution of arm type angle;The approximate solution of the second joint angle is obtained based on the simplified SRS model;The mapping relationship between arm type angle and the second joint angle;Joint angle solution output flow based on one-dimensional search numerical iteration;Inverse solution discrimination, inverse solution unification under the constraint of configuration index and task-oriented configuration selection criterion.Under the premise of ensuring end pose accuracy, the arm type angle control quantity is explicitly introduced into the inverse kinematics solving process, the corresponding relationship between the arm type angle and the second joint angle is established, the complex redundant inverse kinematics solving is converted into the iterative search problem of single joint variable, the high-precision tracking of expected arm type angle is realized, and the real-time control demand is met.

The application discloses a kind of inverse kinematics solving methods of collaborative robot, comprising the following steps: establishing connecting rod coordinate system, and set the rotation angle of each joint axis as joint variable;Obtained positive kinematics equation by kinematics modeling analysis;Analysis and solution inverse kinematics, first carry out the introduction of multiple variables, when the solution of next relevant joint variable, it is reserved in the calculation process;According to the mathematical association and dependent relationship between each joint variable obtained, the desired inverse kinematics solution result can be obtained without other auxiliary screening matching algorithm.It is different from the structure of general industrial robot that the mechanical structure of collaborative robot is different, and its general solution will be more difficult.The present application realizes the uniqueness confirmation of the inverse kinematics of collaborative robot multiple solutions, which can guarantee that there is no potential jump and other system risks in the inverse kinematics of robot.

The invention relates to the technical field of mechanical arm control, and discloses an approximation damping reciprocal function feature solving method and system for singular point avoidance. The solving method is applied to mechanical arm control equipment, and specifically comprises the following steps that S101, the geometrical configuration and joint parameters of a mechanical arm are obtained, a complete kinematics model frame is established, a forward kinematics equation is established through a Denavit-Hartenberg parameter method, the mapping relation between the pose of an end effector and joint variables is determined, and the pose of the end effector is determined; deriving a speed level Jacobian matrix of the mapping relation by adopting a differential transformation method; s102, performing algebraic analysis and decomposition on the obtained Jacobian matrix, identifying key algebraic factors causing matrix singularity, and establishing corresponding singularity factor libraries for different mechanical arm configurations; according to the adaptive damping reciprocal function constructed based on the composite exponential function, the numerical stability in a singular point neighborhood is ensured by optimizing parameter combination, and the problem of joint velocity kick caused by damping mutation is thoroughly eliminated.