The methods of position control for an assistive standing-up robot is studied. Position control tests are carried out under different frequencies using position/velocity feedback control. The position accuracy of sliding joint of the assistive standing-up robot is higher, but that of rotary joint is lower. The velocity feed-forward control is added based on feedback control and new tests are carried out. The results show that the position accuracy of two joints of the assistive standing-up robot is significantly improved by adding velocity feed-forward control, especially for rotary joint. It proves that the position accuracy of assistive standing-up robot is effectively improved by adding the velocity feed-forward control based on feedback control.
 张晓玉.我国个人移动辅助器具领域的发展现状和趋势[C]//第七届全国康复医学工程与康复工程学术研讨会论文集.2010: 8-9. Zhang X Y. Aids for personal mobility for the development of the status quo in China[C]//Proceedings of the 7th Conference on Rehabilitation Medical Engineering and Rehabilitation Engineering. 2010: 8-9. Kim J Y, Popovic M R. Dynamic modeling and torque estimation of FES-assisted arm-free standing for paraplegics[J]. IEEE Transactions on Neural Systems and Rehabilitant Engineering, 2006, 14(1): 46-54.  Kuzelicki J, Bajd T, Kamnik R. FES assisted sit-to-stand transfer in paraplegic person[C]//Proceedings of the 22nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society. Piscataway, NJ, USA: IEEE, 2000: 2247-2250. Lau B, Guevremont L, Mushahwar V K. Strategies for generating prolonged functional standing using intramuscular stimulation or intraspinal microstimulation[J]. IEEE Transactions on Neural Systems and Rehabilitation Engineering, 2007, 15(2): 273-284.  Doheny E P, Fan C W, Foran T. An instrumented sit-to-stand testused to examine differences between older fallers andnon-fallers[C]//33rd Annual International Conference of the IEEEEngineering-in-Medicine-and-Biology-Society. Piscataway, NJ, USA:IEEE, 2011: 3063-3066. Mihelj M, Munih M. Unsupported standing with minimized anklemuscle fatigue[J]. IEEE Transactions on Biomedical Engineering,2004, 51(8): 1330-1340.  Senanayake C, Senanayake S M N A. Emerging roboticsdevices for therapeutic rehabilitation of the lowerextremity[C]//IEEE/ASME International Conference on AdvancedIntelligent Mechatronics. Piscataway, NJ, USA: IEEE, 2009:1142-1144. Kamnik R, Bajd T.Human voluntary activity integration in the control of a standing-uprehabilitation robot: A simulation study[J]. Medical Engineering& Physics, 2007, 29(9): 1019-1029.