基于模型预测控制的双轮平衡轮椅轨迹跟踪

为实现双轮平衡轮椅的自主循迹出行,根据欧拉-拉格朗日方程建立双轮平衡轮椅的动力学模型,通过差动几何模型建立运动关系,采用Pure Pursuit算法规划系统的目标运动状态,分别采用模型预测控制(model predictive control,MPC)及线性二次型最优控制(linear quadratic regulator,LQR)对双轮平衡轮椅进行平衡控制及运动状态追踪。通过软件Simulink搭建双轮平衡轮椅控制仿真系统,验证双轮平衡轮椅系统分别采用LQR和MPC控制器时的轨迹跟踪效果及跟踪平稳性。仿真结果表明:MPC控制器的动态响应速度较LQR控制器快,MPC控制器作用下车体能快速恢复稳定状态;轨迹跟踪时,MPC控制器在启动转向及终点位置对车体倾角及速度的稳定控制优于LQR控制器。

下肢训练康复轮椅训练模块测试系统的研制

针对带有下肢训练康复功能轮椅的测试平台进行研究,主要包括平台构成、实现原理和测试实施方式。该测试平台可对下肢训练力矩和角度平稳性、平衡训练稳定性和痉挛保护功能进行测试。采用假人主体模拟患者使用工况,利用压力、扭矩和角速度传感器监测数值,创新使用双平行四边形机构和贯通丝杆电机模拟人体移动保持重心的姿态,利用气动卡钳快速制动的特性,配合摩擦盘模拟人体瞬时痉挛的情况测试痉挛保护功能。该测试平台具有测试精度高,判断依据准确,可靠性高等特点,填补了国内对轮椅下肢训练的测试空白。

Bionic autonomous learning control of a two-wheeled self-balancing flexible robot

This paper presents an OCPA （operant conditioning probabilistic automaton） bionic autonomous learning system based on Skinner＇s operant conditioning theory for solving the balance control problem of a two-wheeled flexible robot. The OCPA learning system consists of two stages： in the first stage, an operant action is selected stochastically from a set of operant actions and then used as the input of the control system; in the second stage, the learning system gathers the orientation information of the system and uses it for optimization until achieves control target. At the same time, the size of the operant action set can be automatically reduced during the learning process for avoiding little probability event. Theory analysis is made for the designed OCPA learning system in the paper, which theoretically proves the convergence of operant conditioning learning mechanism in OCPA learning system, namely the operant action entropy will converge to minimum with the learning process. And then OCPA learning system is applied to posture balanced control of two-wheeled flexible self-balanced robots. Robot does not have posutre balanced skill in initial state and the selecting probability of each operant in operant sets is equal. With the learning proceeding, the selected probabilities of optimal operant gradually tend to one and the operant action entropy gradually tends to minimum, and so robot gradually learned the posture balanced skill.

基于模糊PID的爬楼轮椅后腿摆轮机构同步控制策略

后腿是爬楼轮椅的主要执行机构,对轮椅的攀爬、助推及越障起着重要作用,而摆轮作为后腿的重要机构,在轮椅攀爬楼梯时能够改变后腿的助力方向,从而实现轮椅爬楼过程的最大推力,为此设计了模糊比例-积分-微分(PID)摆轮同步位姿调节控制系统。首先,根据爬楼轮椅的功能要求,确定传感器合理的安装位置;其次,搭建控制系统的硬件结构,建立模糊PID同步控制系统模型,制定控制规则,并进行软件开发;最后,对该控制系统进行测试和结果分析。实验结果表明:所提控制系统相较于传统PID控制策略和单一模糊控制策略降低了调节过程中的超调现象和同步稳态误差。

基于STM32的多功能自动平衡轮椅设计

随着我国人口老龄化不断加剧,市场对电动轮椅乃至智能轮椅的需求逐渐增加。本设计基于STM32单片机,实现了轮椅座椅平面在一定范围内自动平衡的功能。本设计还集成了其他诸多实用功能,包括定位信息收发、人体生理信息监控、摇杆控制、轮椅制动、超声波障碍物检测等物联网功能,并开发了供亲属使用的微信小程序。系统通过数字运动处理器进行姿态数据结算,输出平衡电机控制力矩,实现座椅平面自动调节。经过广泛的市场调查,设计的自动平衡功能获得了用户的良好评价,有效填补了智能电动轮椅市场的部分空缺。

Control System of Two-Wheel Self-Balancing Vehicle

This study mainly concerns a motion model and the main control algorithm of two-wheel self-balancing vehicle models.Details of the critical parameters fetching and output value of two-wheel self-balancing vehicle models are introduced,including those concerning balance control,speed control and direction control.An improved cascade coupling control scheme is proposed for two-wheel vehicles,based on a proportional-integral-derivative(PID)control algorithm.Moreover,a thorough comparison between a classic control system and the improved system is provided,and all aspects thereof are analyzed.It is determined that the control performance of the two-wheel self-balancing vehicle system based on the PID control algorithm is reliable,enabling the vehicle body to maintain balance while moving smoothly along a road at a fast average speed with better practical per-formance.

轮椅太极对A～B级脊髓损伤坐位下臀部受压中心(COP)及坐位平衡的影响

目的:观察轮椅太极对A^B级脊髓损伤坐位下臀部受压中心(COP)及坐位平衡的影响。方法:将40例A^B级脊髓损伤患者随机分为试验组(20例)和对照组(20例),对照组给予常规运动治疗(含平衡训练),试验组则在常规运动治疗(除平衡训练外)基础上配合轮椅太极训练,采用压力测试系统(Pressure Testing System)及功能性前伸试验(Functional Reach Test)评估坐位压力及坐位平衡的变化情况。结果:治疗后,两组患者功能性前伸得分均显著改善(P<0.05),但组间差异无统计学意义,(P>0.05)。同时,坐位下臀部受压中心(COP)治疗前后比较差异均无有统计学意义(P>0.05)。结论:常规平衡训练及轮椅太极对A^B级脊髓损伤患者的坐位平衡能力均有改善作用。