A lower extremity exoskeleton, SJTU-EX, is proposed, which mainly aims to help soldiers and workers to support a payload in motions. To solve the issues of the exoskeleton-environment and exoskeleton-human interaction...A lower extremity exoskeleton, SJTU-EX, is proposed, which mainly aims to help soldiers and workers to support a payload in motions. To solve the issues of the exoskeleton-environment and exoskeleton-human interactions, four types of foot contact are proposed based on their different kinematic characteristics. By the combination of single leg states, sixteen exo- skeleton states are presented using a series of meaningful notations from the topological point of view. The generalized function set （GF set） theory is employed to achieve the kinematic characteristics of the end effectors in different states. Moreover six mathematical formulations of the dynamics of the exoskeleton and its interactions with the human wearer are developed for different exoskeleton states. The applicability and potential of the proposed classification method are demonstrated by analyzing common lower limb motions, which are described concisely by a sequence of notations. Finally, a new concept of characteristic state is put forward to uniquely indicate the type of motion.展开更多
An innovative lower extremity exoskeleton with hybrid leg structures is proposed in this paper. The compound pendulum model is applied to analyze the swing motion during walking for the wearer and the exoskeleton resp...An innovative lower extremity exoskeleton with hybrid leg structures is proposed in this paper. The compound pendulum model is applied to analyze the swing motion during walking for the wearer and the exoskeleton respectively. The expression of the resonant period for the human lower limb is obtained and the optimum stride frequency, at which the energy expenditure for walking is the least, coincides with the stride frequency of strolling well. As for the exoskeleton, the relationship between the inertial parameters and the resonant period of the hybrid leg is established. To minimize the walking energy cost for the exoskeleton, the inertial parameter design must guarantee that the resonant period of the hybrid leg coincides with the actual stride period of the wearer. The resonant period of the hybrid leg is also influenced by the scissor angle which determines the distance between the hip and the ankle of the lower extremity exoskeleton （SJTU-EX） and can be adjusted to match different stride frequencies of various motions by the proper scissor angle planning.展开更多
文摘A lower extremity exoskeleton, SJTU-EX, is proposed, which mainly aims to help soldiers and workers to support a payload in motions. To solve the issues of the exoskeleton-environment and exoskeleton-human interactions, four types of foot contact are proposed based on their different kinematic characteristics. By the combination of single leg states, sixteen exo- skeleton states are presented using a series of meaningful notations from the topological point of view. The generalized function set （GF set） theory is employed to achieve the kinematic characteristics of the end effectors in different states. Moreover six mathematical formulations of the dynamics of the exoskeleton and its interactions with the human wearer are developed for different exoskeleton states. The applicability and potential of the proposed classification method are demonstrated by analyzing common lower limb motions, which are described concisely by a sequence of notations. Finally, a new concept of characteristic state is put forward to uniquely indicate the type of motion.
文摘An innovative lower extremity exoskeleton with hybrid leg structures is proposed in this paper. The compound pendulum model is applied to analyze the swing motion during walking for the wearer and the exoskeleton respectively. The expression of the resonant period for the human lower limb is obtained and the optimum stride frequency, at which the energy expenditure for walking is the least, coincides with the stride frequency of strolling well. As for the exoskeleton, the relationship between the inertial parameters and the resonant period of the hybrid leg is established. To minimize the walking energy cost for the exoskeleton, the inertial parameter design must guarantee that the resonant period of the hybrid leg coincides with the actual stride period of the wearer. The resonant period of the hybrid leg is also influenced by the scissor angle which determines the distance between the hip and the ankle of the lower extremity exoskeleton （SJTU-EX） and can be adjusted to match different stride frequencies of various motions by the proper scissor angle planning.
