Abstract: A method of active freewheel control (AFW) of a remote-operated pipe crawler vehicle provides a means of retrieving the pipe crawler vehicle after remote visual inspection of a pipe or other passage through a camera assembly on the pipe crawler vehicle. After the vehicle is remotely driven through the pipe to an inspection location, an operator may engage one or more modes to reverse the drive system of the vehicle back to the entry point of the pipe. The AFW system employs an arrangement of integrated sensors and software to intelligently control a simplified drive system that allows the crawler vehicle to assist motion when a tether connecting the vehicle to a control unit is pulled on.

Abstract: A magnetic robot crawler designed to efficiently adhere and traverse a ferrous surface partially or fully underwater, regardless of orientation. The crawler includes a vehicle body, a plurality of drive wheel assemblies, and a plurality of gearmotors. The vehicle body houses the necessary electronical components. The drive wheel assemblies are peripherally and externally mounted to the vehicle body in order to support the vehicle body. Each of the drive wheel assemblies is torsionally coupled to a corresponding gearmotor. Each of the drive wheel assemblies includes a tubular housing, a wheel, an annular cavity, and a semi-annular magnet. The wheel is rotatably mounted to the vehicle body through a tubular housing and is torsionally coupled to the corresponding gearmotor through a magnetic coupling. The annular cavity laterally traverses into the wheel and receives the semi-annular magnet. The semi-annular magnet stays stationary while the wheel turns about the semi-annular magnet.