MS student Bonhyun Ku with advisor A. Banerjee

Animal-like robots, such as snake robots, quadruped robots, and humanoid robots, require dynamic motion and simple mechanical design. However, most have complicated mechanical designs and low actuation speed due to conventional dc motors with gears. We propose a design and architecture for an alternative electromechanical actuation system. This actuator, a stack of E-cores, utilizes electromagnetic force induced by controlled current through coils while varying the air-gap distances. Currently, the system comprises six stacked modules, as shown in Figure 2.

Bonhyun Ku animal-like robot

Figure 2: Animal-like robot with distributed and scalable electromechanical actuator

The E-core serves dual purposes as a flux-carrying element and heat sink for the power converters. The proposed design is scalable, modular, and it simplifies the mechanical structure of an actuator. Buck converters for the system are designed and mounted on each E-core. The actuator’s force and torque are controlled by a proportional-integral current controller. This research is supported by Power Affiliates, the Helm Fund, and the Grainger Center for Electric Machinery and Electromechanics.