Actuation and position estimation of a passive mobile end effector from across a thin wall for heavy-duty aircraft manufacturing

A passive mobile robot carrying a heavy manufacturing tool is activated from across a thin wall. The mobile robot placed within a confined space has no tether and no local battery, but is powered from an outside robot through magnetic coupling. A pair of magnetic feet allows the passive inside robot to hang from a ceiling and walk across a wall. A heavy manufacturing tool held in the middle of the passive inside robot is activated with a Lorentz force actuator-this is also activated from the outside robot. A set of Hall effect sensors on the outside robot detect the magnetic field created by the passive robot in order to estimate the position of the inside robot. First, the task conditions and functional requirements are described, and the design concept of the passive mobile robot is presented. An electro-magnetic model for predicting magnetic field strength and load bearing capacity is used to facilitate design as well as to estimate and control the position of the passive inside robot. A proof-of-concept prototype system is designed and built for application to aircraft manufacturing.