Establishing the Lagrangian equation of double complex pendulum system and obtaining the dynamic differential equation,we can analyze the motion law of double compound pendulum with application of the numerical simula...Establishing the Lagrangian equation of double complex pendulum system and obtaining the dynamic differential equation,we can analyze the motion law of double compound pendulum with application of the numerical simulation of RK-8 algorithm.When the double compound pendulum swings at a small angle,the Lagrangian equation can be simplified and the normal solution of the system can be solved.And we can walk further on the relationship between normal frequency and swing frequency of double pendulum.When the external force of normal frequency is applied to the double compound pendulum,the forced vibration of the double compound pendulum will show the characteristics of beats.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
基金NUIST’s curriculum reform project of“integration of specialty and innovation”.
文摘Establishing the Lagrangian equation of double complex pendulum system and obtaining the dynamic differential equation,we can analyze the motion law of double compound pendulum with application of the numerical simulation of RK-8 algorithm.When the double compound pendulum swings at a small angle,the Lagrangian equation can be simplified and the normal solution of the system can be solved.And we can walk further on the relationship between normal frequency and swing frequency of double pendulum.When the external force of normal frequency is applied to the double compound pendulum,the forced vibration of the double compound pendulum will show the characteristics of beats.
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.
