Abstract: A substantially achromatic multiple element compensator system for use in wide spectral range (for example, 190-1700 nm) rotating compensator spectroscopic ellipsometer and/or polarimeter systems. Multiple total internal reflections enter retardance into an entered beam of electromagnetic radiation, and the elements are oriented to minimize changes in the net retardance vs. the input beam angle resulting from changes in the position and/or rotation of the system of elements.

Abstract: A method is provided wherein when an auxiliary device is being powered by the PTO driveline the PTO clutch is periodically slowly ramped down in pressure until slippage is detected in the clutch. Slippage is determined by monitoring the shaft speed into the clutch as well as the shaft speed downstream of the clutch. By determining the commanded pressure where slippage occurred, the equivalent engine power that is going to the auxiliary function is calculated. With this information, the proportion of the engine load signal that is going to the auxiliary function versus the drive wheels is determined. After slip is detected in the PTO clutch, pressure is ramped back up in the clutch so as to minimize the amount of slippage.

Abstract: A method is provided for shifting a powershift transmission in a vehicle having an engine controlled by an electronic engine control unit and a powershift transmission controlled by an electronic transmission control unit. During a shift the powershift transmission has an off-going clutch and an on-coming clutch. The method includes determining a Predicted Off Slip Pressure for the off-going clutch and determining a Predicted On Slip Pressure for the on-coming clutch, both as a function of engine load. The Predicted Off Slip Pressure is a pressure at which the off-going clutch would start to slip, and the Predicted On Slip Pressure is a pressure at which the on-coming clutch would start to transmit torque. Thereafter, the method includes rapidly reducing off-going clutch pressure, P-off, to a pressure which is slightly higher than the Predicted Off Slip Pressure, and rapidly increasing on-coming clutch pressure P-on to a pressure that is slightly lower than the Predicted On Slip Pressure.

Abstract: A brake system for braking a rotatable brake disk includes a primary brake piston engagable with the brake disk and a secondary brake piston engagable with the primary brake piston and operable to move the primary brake piston into engagement with the brake disk. Both pistons are operable in response to fluid pressure. A primary brake valve controls communication of fluid pressure to the primary brake piston. A secondary brake valve controls communication of fluid pressure to the secondary brake piston.