Concept for an SMA-Actuated Camera Gimbal

Abstract:
Camera drones use gimbals to track targets and to compensate aircraft movement. The gimbal contributes significantly to the weight of a drone, thus offering a major potential for weight reduction. This paper presents a concept for a novel light-weight camera gimbal driven by thermal Shape Memory Alloy (SMA) wires. The gimbal was designed with two degrees of freedom, each covering an angular range of ±45deg with a speed of 200deg/s. The concept combines an adapted “Agile Eye” parallel kinematics with two “Inverse Pendulum”-type SMA actuators. An instrumented setup was developed for performance optimization of the SMA actuators during the assembly process, thus avoiding delays and cost of prototype iterations. Results indicate that a reduction of gimbal weight by a factor of almost 25 compared to a commercial electromagnetic reference gimbal will be feasible.