A new optical pickup suspension desig

A new beam!type optical pickup suspension of a CD player or a CD!ROM driver is developed[ Simply using the sensitivity analysis rather than sophisticated optimization tools\ we show how a new good pickup suspension can be designed to satisfy certain conditions[ Unlike existing suspension systems\ the present suspension structure consisting of four beams has two rectangular bends in both ends of each beam[ The present choice of the rectangular bend with optimally selected thickness and width of the beams provides very good low!frequency dynamic characteristics of the pickup ^ the natural frequencies in two major motion directions are within the target range\ and unwanted natural frequencies are made as high as possible[ The development of the present suspension structure consists of two parts[ The initial suspension system with the uniform width is determined based on the simpli_ed analytic pickup model proposed in this work[ Then by performing the sensitivity analysis for the resonance frequencies\ based on the detailed _nite element model of the initial suspension system\ an optimal suspension width variation is determined[ It is shown that the sensitivity analysis even without sophisticated optimization algorithms is extremely useful in actual engineering practice with a tight development schedule constraint[ The strain energy is utilized to _nd the optimal treatment location of damping bonds which can control the quality factors at major resonances within the allowance limit[ The experiments performed on the present sample model indeed yielded sat! isfactory results and its mass production is in progress