Extended Dynamic Model for the UR16e 6-Degree-of-Freedom Robotic Manipulator.

Area of Science:

• Robotics
• Mechanical Engineering
• Control Systems

Background:

• Manufacturers often provide limited dynamic information for industrial robots.
• Accurate dynamic models are essential for advanced control and simulation.
• Existing models may not fully capture complex behaviors like actuator dynamics and friction.

Purpose of the Study:

• To develop and validate an Extended Analytical Dynamic Model (EADM) for the UR16e 6-Degree-of-Freedom (DoF) industrial robot.
• To incorporate actuator dynamics and a friction model into the robot's dynamic representation.
• To establish a rigorous validation methodology for the developed dynamic model.

Main Methods:

• A two-stage validation process was employed using a Multibody Physical Model (MPM) in MATLAB/Simscape Multibody as a reference.
• Stage 1: Compared the inverse dynamics torque of the Analytical Dynamic Model (ADM) against the MPM.
• Stage 2: Tested the EADM and MPM under a Proportional-Derivative Computed Torque Control (PD-CTC) scheme with Cartesian trajectories, comparing joint torques and positions.

Main Results:

• The ADM showed minimal torque errors (10^-17 to 10^-13 Nm) in the first validation stage.
• The EADM demonstrated bounded position (≤4×10^-4 rad) and torque errors (≤0.4 Nm for joints 1-3, ≤0.05 Nm for joints 4-6) in the second stage.
• The validation methodology confirmed the EADM's accurate representation of the MPM's dynamic behavior.

Conclusions:

• The developed Extended Analytical Dynamic Model (EADM) provides an accurate dynamic representation of the UR16e industrial robot.
• The proposed two-stage validation methodology, including torque-level checks, is effective for assessing robot dynamic models.
• The EADM is suitable for applications requiring precise dynamic simulation and control of the UR16e robot.