MEAM Seminar: “Leveraging Impedance Properties for Free Self-Sensing in Actuators for Compact Robots”

Self-sensing actuators provide a compelling approach to designing compact robotic systems by integrating sensing capabilities directly into the actuator, eliminating the need for external sensors. This presentation, titled “Leveraging Impedance Properties for Free Self-Sensing in Actuators for Compact Robots,” highlights how the intrinsic impedance properties of actuators—resistance, inductance, and induced EMF—can be harnessed to achieve low-volume solutions of self-sensing actuators. Evidence for this approach is demonstrated through three projects: a self-sensing I-cord knitted SMA actuator that uses resistance measurements to monitor its state, applied in an inchworm robot and a gripper; a custom PET solenoid actuator that utilizes induced EMF to sense movement and velocity, enabling applications such as an origami-inspired bistable gripper and a facial reanimation device acting as an artificial muscle; and a custom acrylic linear solenoid actuator that leverages inductance to self-sense plunger position, demonstrated as an active valve in underwater swimming robots. These examples illustrate the potential of impedance-based self-sensing to streamline actuator design, enhance functionality, and enable new possibilities in robotics across domains.