Abstract: A method is disclosed to smooth the ride of a seat occupant by controlling the damping force of a fluid damper positioned between the seat and base. The method selects between different subprocesses to minimize the ride discomfort and to minimize peak seat accelerations and endstop jerks. The controller uses the input from the different subprocesses to create the best ride for the immediate operational conditions.

Abstract: A data-logging truck control system controls magnetorheological fluid dampers to protect a data-logging equipment payload of a data-logging truck from vibration and/or impulse shock forces.

Abstract: The air flow rate through a rock drill bit is measured while the drill bit is connected to a drill string. A tube of a manometer is inserted into a channel of the drill bit while an air flow is conducted through the drill string and channel, whereby the manometer measures a pressure of the air flow in the channel. From that measurement, a nominal air flow rate is calculated. The nominal air flow rate is corrected as a function of at least one parameter selected from: a difference between a temperature of air entering the drill bit and a temperature of air ambient to the drill bit, and a height of the drill bit above sea level.