目前国家拖拉机质量监督检验中心做中小功率拖拉机牵引试验用的负荷车是由上海50型拖拉机改装而成的。十几年来，该机及所配试验仪器一直保持较好的可靠性。随着科学技术的发展，负荷车在试验中也暴露出一些不足之处。为提高试验数据采集的准确性，克服试验中人为因素的影响，? At present, the National Tractor Quality Supervision and Inspection Center to do small and medium-power tractor traction test load car is converted from the Shanghai 50 tractors. More than a decade, the aircraft and the test equipment has been maintained with good reliability. With the development of science and technology, the load vehicle also revealed some shortcomings in the experiment. In order to improve the accuracy of experimental data acquisition, to overcome the human factors in the experiment,