9532041 DeBra Thermal control and temperature gradients in machine tools and metrology instruments are fundamental limitations to precision engineering. A way to minimize these limitations is using hydraulic actuation and sensing, because of its high and efficient transfer of energy. This approach is also compatible with oil showering, one of the ways thermal control is achieved in ultra-precision manufacturing. This project will develop an ultra precision machine tool based on laminar flow motors and linear actuators, and oil differential gages for straightness and yaw compensation. These components were developed at Stanford University, in part with NSF Strategic Manufacturing Initiative support, to eliminated control of hydraulic actuators by throttling which leads to turbulence, noise and vibration. The major research efforts will be on development of compatible hydraulic sensors and integration of the quite actuators in an ultra precision, quiet hydraulic diamond turning machine. The impact of this research is primarily on the infrastructure for precision engineering and ultra precision machine tools. It promises better thermal control at lower cost than is possible with existing ultra precision machines and equipment.