Large size optical aspheric lens is an important component in optical engineering. Aiming at the demand of precision processing for optical aspheric lens, this paper develops a precision grinding technique for large size optical aspheric lens. Based on precision surface grinding machine (MGK7160), grating-type parallel grinding method is put forward to realize grinding paths planning for optical aspheric lens. An on-machine measurement system is built to obtain surface measurement and evaluation after grinding. In order to ensure machining precision and efficiency, a diamond truer which self-developed is adopted to precision dress for arc diamond wheel. Finally, the experiment of precision grinding and error compensation validates machining accuracy for large size optical aspheric lens.

In order to weld the skin and skeleton of bus roof, it analysis the welding process of bus Outer Roof-panels , and specify the weld area and solder joint distance of outer roof-panel firstly , then built a single-sided double-point resistance welding experiment platform for bus outer roof-panels, the platform consists of guide、gantry、gantry moving mechanism、 pneumatic torch、electrode support mechanism、transformers、torch lateral movement organizations and torch longitudinal movement phenomenon . it set the unevenness of the skin and the skeleton as 1mm, single-sided double-point resistance welding experiment was conducted on the welding experiment platform. The experimental results of welding area visual examination and tear experiments indicate that welding heat will penetrate the skeleton when the welding current is greater than 11.0KA;the welding Reliability of galvanized steel is better than low carbon steel.