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roboticslibrary / rl

The Robotics Library (RL) is a self-contained C++ library for rigid body kinematics and dynamics, motion planning, and control.
https://www.roboticslibrary.org/
BSD 2-Clause "Simplified" License
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Customizing Initial Position and Implementing Inverse Kinematics for the Robotic Arm #75

Closed lgzid closed 8 months ago

lgzid commented 9 months ago

Hello, I am using the robotics library for motion planning of a mobile robotic arm.

My robotic arm is imported through a URDF file, but the initial position of the entire arm is determined by the URDF upon import. Subsequent inverse kinematics calculations are based on this initial position.

Currently, I need to move the robotic arm to a specified position after importing, for example, from the initial position (0,0,0) to (10,0,0), and then perform inverse kinematics. Is there a method in this library to achieve this?

rickertm commented 8 months ago

As you mention a URDF file, I assume you are using either rl::mdl::JacobianInverseKinematics or rl::mdl::NloptInverseKinematics for solving the inverse kinematics of your robot arm? These implementations work on a rl::mdl::Kinematic model and their solve() function uses the current joint position of the model as starting point for their iterative approach. This position can be set before solving via rl::mdl::Model::setPosition. Please note that these iterative solvers retry with a random joint position in case the iterations do not produce a valid solution within their limits. This can be disabled via rl::mdl::IterativeInverseKinematics::setRandomRestarts.

lgzid commented 8 months ago

Thank you for your response. I have implemented the above functionality using the::rl::math::Transform& world();function. Thanks!