Switched electromechanical dynamics for transient phase control of brushed DC servomotor

Area of Science:

• Robotics and Control Systems
• Electromechanical Engineering
• Applied Physics

Background:

• Robotic tasks frequently involve transient or aperiodic motions, exceeding the capabilities of models focused on steady-state behavior.
• Existing electromechanical servomotor models often neglect the crucial switching power converter circuits essential for precise motion control.
• There is a need for comprehensive models that integrate electrical and mechanical dynamics for general robotic applications.

Purpose of the Study:

• To establish a multi-domain framework for switched electromechanical dynamics in servomotor systems.
• To enable analysis and control of servomotors during general aperiodic tasks, including transient phases.
• To develop a more accurate model for servomotor power consumption for energy optimization.

Main Methods:

• Derived switched electromechanical dynamics from individual DC motor, gear train, and H-bridge circuit models.
• Integrated all switching configurations, including on-state, off-state, and dead time, into a coupled model.
• Employed cycle averaging with piecewise analytical solutions to manage diverse temporal scales.

Main Results:

• Validated the model's predictive accuracy against experimental data for dynamic braking and trajectory following tasks.
• Demonstrated optimal control and energy analysis using the derived servomotor power consumption model.
• Showcased that the developed power consumption model achieves true optimality compared to common proxy models.

Conclusions:

• The developed multi-domain framework provides a robust method for analyzing and controlling servomotors in general aperiodic tasks.
• The validated model accurately predicts servomotor behavior during transient phases and enables precise energy optimization.
• The approach is applicable to a wide range of electromechanical systems with switching-based control, enhancing robotic system efficiency.