Groundhog knee deep in mine muck.2D mine map produced by Groundhog.3D mine map snapshot produced by Groundhog.Ferret1 deployed into the Mellon Institute void.Second generation Ferret with higher power laser range finder.Ferret2 scan of a limestone mine after a domeout, Kansas City, Kansas.Borehole deployable, inflatable mobile robot concept.
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Hydraulic Groundhog
Trouble shooting the hydrualic system.Hydrualic Layout

Groundhog's mission in life was to go into an abandoned mine. Unfortunately, abandoned mines often contain pockets of methane and other explosive gases. Therefore, Groundhog needed to be made explosion proof. The brushed DC motor from the golf cart drive train would therefore have to be replaced. Also, all of the exposed wiring and contacts would need to be placed in explosion proof enclosures. To simplify this task, the team decided to put all of the electronics in a single large explosion proof box and switch from electric locomotion to hydrualic locomotion.

Before we integrated the hydraulics into the vehicle, it was decided to test the hyraulics independent of rest of the system. This proved to be a very good decision since the hydraulic manifold that was used had been mismanufactured. Drilling another half inch into the maniforld solved the problem. The manifold was reintegrated into the benchtop test, and everything worked as expected.

Porting of the hydraulics through the side of the explosion proof box.Integrated Hydraulics

Once the hydraulic system was shown to work, the task of integrating the mass of hoses and wires into the tight confines of the explosion proof box began. New hoses were made to fit the constraints of the box. Once the manifold was fully plumbed, the hoses going to the actuators were routed outside of the XP box.

In this way, the electric pump motor for the hydraulics as well as the solenoid valves on the manifold were all contained within the explosion proof box. The only things exiting the box were the hyraulic lines going to the drive motor and steering cylinder. Integration of the electronics to control the robot occured in the course of a fifty hour marathon in conjunction with the hydraulic integration. At the end of this effort, Groundhog was a computer controllable, hydrualically powered vehicle.

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