移乘背抱护理机器人舒适性生物力学模型分析

Biomechanical Model Analysis of the Comfortableness of a Piggyback Nursing Robot for Transfer Tasks

为探索移乘背抱护理机器人人机交互力学特性与被护理人舒适性感受的潜在关联,研究显性的人机接触力相对于人体生物力学特性的映射关系,揭示影响被护理人舒适性的主要作用肌群,提出了舒适性测试试验与AnyBody背抱运动人体生物力学模型相结合的方法.从被护理人的肌肉激活程度入手,对移乘背抱护理机器人背抱运动舒适性特征进行了分析.首先,介绍了移乘背抱护理机器人典型结构工作原理并进行了运动学分析,在此基础上搭建了舒适性测试试验系统,基于主观舒适性评分规划了服务于试验的基础运动轨迹,并通过试验得到了人机主要接触部位力学信息.然后,以试验数据为边界条件构建了基于AnyBody的背抱运动人体生物力学模型,依托逆动力学仿真分析得到了肌肉激活程度,并对比舒适性测试肌肉激活程度验证了仿真模型的有效性.最后,结合人机主要接触部位受力、肌肉激活程度及主观舒适性评分综合分析了移乘背抱护理机器人背抱运动舒适性特征,明确了影响被护理人舒适性的主要作用肌群.结果表明:影响被护理人舒适性的主要作用肌群有7个,且被护理人胸部压力与腋下压力值大小分别与影响其躯干和上肢舒适性的肌肉激活程度呈正相关.可通过建立胸部压力与腋下压力值相关的加权函数有效描述不同被护理人整体舒适性特征,为移乘背抱护理机器人舒适性运动控制提供了理论依据.

To explore the potential relationship between the mechanical characteristics of human-computer interaction of the piggyback nursing robot for transfer tasks and the comfort of care receivers,study the mapping relationship between the dominant human-computer contact force and human biomechanical characteristics,and reveal the main functional muscle groups that affect the comfort of care receivers,the method of combining a comfortableness experiment with a biomechanical model of piggyback motion based on the AnyBody was presented.Starting with the degree of muscle activation of care receivers,the comfortableness characteristics of the piggyback motion of the robot were analyzed.First,the working principle of the typical structure of the robot was introduced,and its kinematics was analyzed.Accordingly,its comfortableness experiment system was built,the basic motion trajectory serving the experiment was planned based on the subjective comfort score,and the mechanical information of the main contact parts of the human and machine was obtained through the experiment.Then,with experimental data as the boundary condition,a human body biomechanical model of piggyback motion based on AnyBody was constructed.The degree of muscle activation was obtained through inverse dynamics simulation analysis,and the effectiveness of the simulation model was verified by comparing the muscle activation degree of the comfortableness experiment.Finally,combined with the force on the main contact parts of the human and machine,degree of muscle activation,and subjective comfortableness score,the comfortableness characteristics of the robot were analyzed comprehensively,and the main functional muscle groups that affect the comfortableness of care receivers were identified.The results show seven main functional muscle groups that affect the comfortableness of care receivers,and the chest and axillary pressures are positively correlated with the activation degree of the main muscles that affect the comfortableness of the trunk and upper limbs,respectively.The overall comfortableness characteristics of care receivers can be effectively described by establishing a weighting function related to chest and axillary pressures,which provide a theoretical basis for the comfort motion control of the robot.