Duty Cycle for Low Energy Operation of a Personal Conditioning Device

The Roving Comforter (RoCo) is an innovative personal thermal management technology that provides ultimate personal thermal comfort for individuals in inadequately or even unconditioned environments. It is a miniature heat pump system mounted on a robotic platform capable of autonomously following individuals to deliver comfort by directing hot or cold air through automatically controlled nozzles. This allows buildings to relax their thermostats up to 4°F (2.2°C), leading to energy savings anywhere between 10 to 30% depending on climatic conditions. Since RoCo is a portable device, it needs to be operated on battery. A smaller battery pack will require frequent charging making it inconvenient for the users, while a bigger battery pack will add to the weight of the device leading to higher power consumption during motion. To address this problem, a multi-physics model for the operation that incorporates thermodynamics, electricity and mechanics of RoCo is developed and two duty cycles analyzed. Strategies for the operation of RoCo are provided from the observations of results.

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