Advanced 3D Control Techniques for Powered Wheelchairs

在美国，有超过20万人使用电动轮椅（epw）作为他们的主要交通工具。电动轮椅为下肢和上肢有障碍的人提供功能性的行动能力。虽然电动轮椅在过去20年里取得了巨大的进步，但自20世纪80年代初以来，控制算法几乎没有改变。简单的比例积分（PI）控制器用于电动轮椅的速度控制是过时的，并且在干扰、传感器不确定性和负载变化下表现不佳。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。设计人员成功地实现了一种驱动式助力轮椅的共享控制系统。此外，建立了EPW的运动学和动力学模型来模拟轮椅的运动，并通过实验结果进行了验证。通过这些初步研究，pi建议设计一个包括速度控制和牵引力控制的电动轮椅鲁棒控制器。基于改进轮椅模型的速度控制算法旨在提高epw在面对外界干扰、参数变化和不确定性时的安全性和有效性。牵引力控制算法处理车轮打滑和轮椅卡死的情况，增加机动性，确保在不利的地面条件下（如潮湿的草地，结冰的人行道，雪）安全导航。最后，他们提出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、在脚轮方向干扰下的运行、室内阈值测试、在坡道、横坡、草地、粗糙表面和光滑表面上的运行。这项试点研究将为开展大规模试验提供手段，旨在在电动轮椅上实施稳健控制器，并测试其对安全性、移动性和社区参与的影响。

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.