Description
The design of a brushless servomotor as well as its application in a low-cost, compliant 7-DOF robot arm are presented. The recent popularity of consumer drones has led to a significant reduction in the cost of high-torque brushless gimbal motors. These motors offer a unique set of advantages for robotic manipulation, but are not typically used for this purpose. A servomotor based on brushless gimbal motors is designed and implemented, including custom electronics and firmware. Cost reduction is achieved by using commodity components and taking system-level considerations into account. The servo achieves active compliance using velocity sensing and high bandwidth field oriented control. Design decisions and tradeoffs are discussed.