There is typically a project in the course of “Mechanism Design” or “Kinematics of Machines”. The purpose of the course project is to apply analysis and synthesis theories to practical mechanisms, strengthen the understanding of theories, improve analysis and synthesis skills of mechanisms, and prepare students to cope with practical engineering problems in industry. The real testing of mechanisms is often missing in the project because of the limited project time and the lacking of a simple and effective testing device. This paper introduces a simple, effective and efficient approach to measure the motion parameters of the analyzed or synthesized mechanisms for the course project. The Calculator Based Ranger (CBR™) System is used to measure motion parameters of mechanisms. The CBR™ system includes a sonic motion detector with a built-in microprocessor, a graphing calculator and some connecting cables. The CBR™ system sends out an ultrasonic pulse and then measures the time it takes for that pulse to return after bouncing off the closest object. When the data is collected, the CBR™ system calculates the distance of the object from the sonic motion detector using a speed-of-sound calculation, and then computes the first and second derivatives of the distance data with respect to time to obtain the velocity and acceleration data. Students first design and analyze the mechanisms. The mechanism performance is analyzed and the output link position, velocity and acceleration plots are generated by Matlab. Pro Engineer or AutoCAD is used for mechanism geometric modeling. The designed mechanisms are then fabricated in the department machine shop by the students. The output motion parameters of the fabricated mechanisms are measured by the CBR™ system. The measured output motion parameters are compared with the analysis results to improve the fabrication precision and measurement accuracy. In this paper, the scotch yoke mechanism is used to show the motion parameter measurement process. Students get hands on experience about the analysis, synthesis, fabrication, and testing of mechanical systems when the CBR™ system is incorporated with the course project.

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