Power Delivery and Low-Power Communication Strategies for a Vacuum-Suspended Inverted Torsion Pendulum Experiment

This paper evaluates electrical power delivery and low-power command strategies for an inverted torsion pendulum designed to demonstrate Digital Micromirror Device–based satellite attitude control via solar radiation pressure. Battery-powered concepts introduce mass penalties and vacuum-compatibility concerns and require chamber access for charging or replacement, thereby motivating alternative architectures. Two questions are addressed: whether low-power wireless communication is sufficient for commanding the microcontroller, and whether the torsion suspension wires can deliver power without significantly altering torsional stiffness. A hardware-in-the-loop test campaign compared WiFi, Bluetooth Low Energy, and infrared communication while profiling startup and steady-state current draw using an OLED display as a surrogate DMD load. A second test delivered external power via tungsten torsion wires using a buck converter and estimated the resulting Joule heating effects. Results show that IR is the lowest-power method, and deep-sleep operation further reduces current consumption to single-digit milliamps. Thermal modeling indicates that wire heating results in micrometer-scale expansion and a negligible change in spring constant, thereby validating torsion-wire power delivery. These results establish a practical electrical architecture for DMD-based torsion pendulum experiments and support integration of the full control electronics for future closed-loop radiation-pressure demonstrations.