【作者】 汪涛；

【导师】 梁杰俊一；

【作者基本信息】 华中科技大学 ， 机械工程， 2023， 硕士

【摘要】 负重能力是开展人类社会生产活动的重要前提之一。也是现场救灾、单兵突击等作战任务中决定成败的关键因素。如何运用工程科学方法设计符合人体负重行走生物力学规律的辅助装置,已成为穿戴式机器人研究中的重点问题。然而,现有负重辅助装置研究对行走稳定性的忽视限制了其实际辅助效果,并存在穿戴者失稳受伤的隐患。如何实现在保证人体负重行走稳定性的前提下进一步降低能耗的目标,是一项极具挑战性的难题。为此,本文聚焦动态负载运动方法对人体稳定性与能耗的影响规律认知,探究弹性背包创新设计理论与控制策略,其主要研究内容如下:（1）揭示人体行走负重行走过程中稳定性随步态周期的变化规律,提出基于力矩分析的人体稳定性评价模型,定性分析同相和反相两种条件下负载幅值比对人体行走稳定的影响。揭示传统倒立摆能耗预测模型与实际代谢结果之间差异的产生原因,通过稳定性评价模型分析结果对传统倒立摆能耗预测模型进行修正,预测负载运动对人体代谢消耗的影响,并提出稳定阈值内最优化代谢的弹性背包设计方法。（2）提出能够实现在同相和反相两种负载运动条件下改变幅值比的弹性背包设计原理,建立弹性背包系统参数辨识方法,揭示弹性背包系统刚度与幅值比的映射关系,通过改变弹簧刚度以及弹簧连接方式精确的改变负载与人体运动的幅值比与相位,得到同相反相两种条件下系列幅值比的弹性背包系统刚度阻尼参数,为用于动态负载的生物力学作用的实验验证提供了装置基础。（3）为验证弹性背包的有效性同时加深对所稳定性评价模型和能耗评价模型的认知,开展了多个不同负载运动状态的负重行走实验,从系统动力学、生物力学等多个维度揭示不同相位与幅值比下人体稳定性的变化规律,并通过代谢消耗、肌肉激活、躯干运动学以及地面反力等对修正后的能量评价模型进行验证。研究发现,在负重15kg行走的实验条件下,保证行走稳定性的不急剧降低的稳定阈值幅值比α_thr≈2,而使得行走能量消耗最小的负载动态运动最优代谢幅值比α_opt<1.5。更多还原

【Abstract】 Load-bearing capacity is an important prerequisite for human productive activities,as well as a crucial factor in determining success or failure in tasks such as disaster relief and individual combat operations.Designing assistive devices that conform to the biomechanical laws of human weight-bearing walking using engineering scientific methods has become a key issue in wearable robot research.However,the neglect of walking stability in current weight-bearing assistive device research limits their practical assistance effect and poses a hidden risk of instability and injury to the wearer.Achieving the goal of further reducing energy consumption while ensuring human weight-bearing walking stability is a highly challenging problem.Therefore,this paper focuses on the cognitive laws of the impact of dynamic load exercise on human stability and energy consumption,and explores the innovative design theory and control strategies of elastic backpacks.The main researches in this dissertation are as follows:（1）Revealing the change law of stability of human walking with loads walking with respect to the gait cycle,proposing a human stability evaluation model based on torque analysis,qualitatively analyzing the impact of load amplitude ratio on walking stability under in-phase and out-of-phase conditions.Revealing the reason for the difference between the traditional inverted pendulum energy consumption prediction model and actual metabolic results,and correcting the traditional inverted pendulum energy consumption prediction model based on the results of the stability evaluation model analysis to predict the impact of load movement on human metabolism consumption,and introducing an elastically suspended backpack design method for optimizing metabolism within stability thresholds.（2）Proposing the elastically-suspended backpack design principle that can change the amplitude ratio under in-phase and out-of-phase load movement conditions,establishing an elastically-suspended backpack system parameter identification method,revealing the mapping relationship between the stiffness of the elastically-suspended backpack system and the amplitude ratio,and accurately changing the load and human motion amplitude ratio and phase by changing the spring stiffness and spring connection method to obtain a series of amplitude ratios under in-phase and out-of-phase conditions.The stiffness and damping parameters of the elastically-suspended backpack system provide a device foundation for experimental verification of the biomechanical effects of dynamic loads.（3）To verify the effectiveness of the elastically-suspended backpack and deepen the understanding of the stability evaluation model and energy consumption evaluation model,load-bearing walking experiments were conducted under different load movement states.The changing rules of human stability under different phase and amplitude ratios were revealed from multiple dimensions such as system dynamics and biomechanics,and the modified energy evaluation model was verified through metabolic consumption,muscle activation,trunk kinematics,and ground reaction forces.The research found that under the experimental conditions of walking with a load of15kg,the threshold α_thr≈2 of the load dynamic motion amplitude ratio that ensures walking stability without sharp decline,and the optimal metabolic amplitude ratio α_opt<1.5 that minimizes walking energy consumption.更多还原