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In line-shaft driven product machinery, torsional deflectionsand vibrations of the camshaft due to the time-varying torque ofvarious cams can cause synchronization problems between the variousstations on the machine. We need to design a testing machine thatwill measure the torsional vibration effects of dynamic torqueloading on a camshaft. This machine will accommodate two cams, eachof which will drive its own spring-loaded translating rollerfollower on a slider mechanism at speeds up to 300 rpm. These camswill be designed to give approximately opposite torque-timefunctions to one another. They can be used singly or in pairs toinvestigate the effectiveness of the addition to a productionmachine of a torque-balancing cam that drives a dummy load. Thecams will be split to allow removal and installation withoutdisassembling the shaft. The torque-time and follower force timefunctions for the primary cam are provided as an excel file P09-20on the books website. The secondary cam will be a mirror image ofthe primary cam to approximately balance the torque. The camshaftin this test fixture must be designed to have torsional deflectionsthat are large enough to be measured by 5000 count per revolution,optical shaft encoders attached at each end of the camshaft, butnot so large as to fatigue fail the shaft. At the same time, wewant the camshaft to be stiff in bending and have a bending naturalfrequency at least 10 times its torsional natural frequency tominimize any coupling effects between bending and torsional modes.Stated another way: what should the shaft diameter be to givesufficient torsional deflections to be measurable under thedesigned loading conditions, but not to create undesirable bendingdeflections or vibrations. Plain bearings should be used to avoidvibrations that would come from rolling element bearings. The testmachine will be driven by a speed controlled PM DC motor through agear reduction unit of your design. Motor selection is also yourresponsibility. What is required is a detailed design of a camshafttorsional vibration test machine including the camshaft, keys,follower trains, bearings, couplings, gearbox, frame and mountinghardware. infinite life is desired.