Abstract: When compiling machine performance data it is advantageous for such data to have been acquired during periods in which the machine was in the same general operating state. The subject invention provides a system for producing historical data regarding machine operating parameters and including a plurality of sensors for producing signals indicative of the level of machine parameters. A control is included for selecting data representative of a first operating parameter in response to a dependency definition being satisfied and for processing the selected data to provide an indication of machine performance.

Abstract: A crawler type vehicle has a car body, a pair of track roller frames connected to the car body and a pair of drive motors each being attached to a respective roller frame. Each of the roller frames are movable between first and second positions at which the roller frame and associated drive motor are a minimum and maximum distance respectively from a longitudinal axis of the vehicle. A first guard assembly is fastened to the car body and is of a construction sufficient for substantially encompassing the drive motors at the first position of the roller frames and for encompassing at least the distal end portions of the drive motors at the second position of the roller frames. A pair of second guard assemblies is mounted on a respective roller frame and movable therewith when the roller frame is moved between the first and second positions.