Advanced 3D Control Techniques for Powered Wheelchairs

电动轮椅的先进 3D 控制技术

• 批准号: 6966173
• 负责人: RORY A. COOPER
• 金额: $ 7.43万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-01 至 2007-08-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6966173
• 关键词: assistive device /technology; biomedical device power system; biomedical equipment safety; energy source; mathematical model; model design /development; person with disability

Over 200,000 people in the United States use electric-powered wheelchairs (EPWs) as their primary means of mobility. Electric-powered wheelchairs provide functional mobility for people with both lower and upper extremity impairments. While electric powered wheelchairs have made great advances over the past 20 years, the control algorithms remain virtually unchanged since the early 1980s. The simple proportional-integral (PI) controller used on electric-powered wheelchairs for velocity control is antiquated, and does not perform well with disturbances, sensor uncertainties and load variations. In addition, wheelchair users may encounter different environments and road conditions when driving outdoors. The PIs have successfully implemented the shared control system for a pushrim activated power assisted wheelchair. In addition, kinematic and dynamic models of an EPW were developed to simulate the wheelchair motion and were validated by experimental results. With these preliminary studies, the PIs propose to design a robust controller for electric powered wheelchairs that includes velocity control and traction control. The velocity control algorithm based on an improved wheelchair model aims to improve the safety and efficacy of EPWs in the face of external disturbances, parameter variations and uncertainties. The traction control algorithm coping with wheel slips and cases where the wheelchair becomes stuck will increase mobility and ensure safe navigation under less favorable surface conditions (i.e., wet grass, iced sidewalk, snow). Finally, they propose to test the algorithms in a pilot setting, including dynamic stability test, obstacle climbing ability test, operation under caster orientation disturbances, indoor threshold test, operation on ramps, on cross slopes, on grass, on rough surfaces and slippery surfaces. This pilot study will provide the means to conduct a large-scale trial designed to implement robust controllers in electric powered wheelchairs and test the effect on safety, mobility, and community participation.

在美国，超过20万人使用电动轮椅(EPW)作为主要的出行方式。电动轮椅为患有下肢和上肢障碍的人提供了功能上的灵活性。虽然电动轮椅在过去20年里取得了很大的进步，但自20世纪80年代初以来，控制算法几乎没有变化。电动轮椅上用于速度控制的简单比例积分(PI)控制器已经过时，并且不能很好地适应扰动、传感器不确定性和负载变化。此外，轮椅使用者在户外驾驶时，可能会遇到不同的环境和路况。PIS已成功实现了电动助力轮椅的共享控制系统。此外，还建立了电动汽车的运动学和动力学模型，对轮椅运动进行了仿真，并通过实验验证了模型的正确性。通过这些初步研究，PIS建议为电动轮椅设计一个稳健的控制器，包括速度控制和牵引力控制。基于改进轮椅模型的速度控制算法旨在提高EPW在面对外部扰动、参数变化和不确定性时的安全性和有效性。处理轮滑和轮椅卡住情况的牵引力控制算法将增加机动性，并确保在不太有利的地面条件(如湿草、结冰的人行道、雪)下安全导航。最后，他们建议在试点环境中对算法进行测试，包括动态稳定性测试、越障能力测试、脚轮方位扰动下的操作、室内阈值测试、在坡道、十字坡、草地、粗糙表面和光滑表面上的操作。这项试点研究将提供进行大规模试验的手段，旨在在电动轮椅上实施稳健的控制器，并测试其对安全性、机动性和社区参与度的影响。