Joint accelerations given joint torques and states
Robotics System Toolbox / Manipulator Algorithms
The Forward Dynamics block computes joint accelerations for a robot model given a robot state that is made up of joint torques, joint states, and external forces. To get the joint accelerations, specify the robot configuration (joint positions), joint velocities, applied torques, and external forces.
Specify the robot model in the Rigid body tree parameter as a
RigidBodyTree object, and set the
Gravity property on the
object. You can also import a robot model from an URDF (Unified Robot Description
Formation) file using
Config— Robot configuration
JointVel— Joint velocities
Joint velocities, specified as a vector. The number of joint velocities is equal to the degrees of freedom (number of nonfixed joints) of the robot.
JointTorq— Joint torques
Joint torques, specified as a vector. Each element corresponds to a torque applied to a specific joint. The number of joint torques is equal to the degrees of freedom (number of nonfixed joints) of the robot.
FExt— External force matrix
External force matrix, specified as a 6-by-n
matrix, where n is the number of bodies in the robot
model. The matrix contains nonzero values in the rows corresponding to
specific bodies. Each row is a vector of applied forces and torques that
act as a wrench for that specific body. Generate this matrix using
externalForce with a
MATLAB Function block
JointAccel— Joint accelerations
Joint accelerations, returned as a vector. The number of joint accelerations is equal to the degrees of freedom of the robot.
Rigid body tree— Robot model