基于导纳控制的轮椅姿态柔顺调节方法研究

Research on compliance adjustment of wheelchair posture based on admittance control

针对目前多姿态智能轮椅姿态调节舒适性差且存在安全风险的问题,提出一种基于导纳控制的轮椅多姿态柔顺控制策略.首先,基于人体生物力学,分析和获取了人体姿态调节过程中的舒适姿态及人-座椅面压力分布图.其次,采用DH参数法对轮椅座椅姿态调节机构进行运动学建模,并以此为基础,以位置环为内环反馈,建立人-座椅面压力外环驱动的导纳控制策略.最后,构建了基于CoppeliaSim和MATLAB的可视化仿真,建立轮椅姿态调节机构的URDF模型,采用LuaSocket实现MATLAB和CoppeliaSim间的通信,进行联合仿真.仿真结果表明轮椅在姿态调节过程中,人与座椅面间的压力变化平稳,可以自适应地调整其位姿,使用结束后能及时回到初始位姿,验证了该方案的可行性与有效性.

In order to solve the problems of poor comfort and safety risks in the posture adjustment process of multi-posture intelligent wheelchair,a wheelchair multi-position compliance control strategy based on admittance control is proposed.Firstly,the comfortable posture and human-seat surface pressure distribution diagram in the process of posture adjustment are analyzed and obtained based on human biomechanics.Secondly,the DH parameter method is used to model the kinematics of the wheelchair seat posture adjustment mechanism,and based on this,with the position loop as the inner loop feedback,an admitance control strategy driven by the human-seat surface pressure outer loop is established.Finally,a joint visual simulation based on CoppeliaSim and MATLAB was constructed,the URDF model of the wheelchair attitude adjustment mechanism was established,and LuaSocket was used to realize the communication between MATLAB and CoppeliaSim.The simulation results show that the pressure between the person and the seat surface changes smoothly,posture can be adjusted adaptively during the posture adjustment process of the wheelchair,and then return to the initial posture in time after the external force disappears,which proves the feasibility and validity of the scheme.