Energy harvesting analysis for Moball, A self-propelled mobile sensor platform capable of long duration operation in harsh terrains

This paper considers the design and optimization of an autonomous electromechanical control and energy scavenging system for the wind-propelled Moball, a spherical mobile sensor platform concept [1, 2]. This mechanism converts mechanical motion to electrical energy, and the same mechanism can function as an actuator to self-generate motion. Simulations of a simplified model on flat ground show that a 2m diameter Moball operating in typical Arctic conditions can generate 1. 8-2.7W of power continuously while being wind-propelled. We also demonstrate a simple motion control algorithm, showing that self-propulsion in windless conditions requires 1-1.5W. Hence, using this mechanism, a Moball can self-generate sufficient energy for long duration missions involving self-propulsion, sensing, and communication in harsh, cold, windy climates (e.g., Polar regions on Earth, or the surface of Titan or Mars) where solar energy may be limited. Simulations with key design parameters are also used to draw general conclusions regarding optimal design for energy recovery. The addition of springs inside the generating mechanism greatly increases the range of wind speeds over which Moball can harvest energy.