Modular Robot Manipulators with Precision Control

Modular robot manipulators have many advantages over conventional integrated robot manipulators, including flexibility, re-configurability, versatility, and low-cost with massive production. However, the lack of control precision has been a long standing drawback in MRM applications until now. In this paper, a VDC-based control and communication system using embedded FPGA (field programmable gate array) logic devices is outlined. This solution is able to push the control precision to a new level without needing joint torque measurements. A test case on a three-module robot using harmonic drives demonstrated that the ratio of the maximum position tracking error to the maximum velocity reached 0.00012 (s).