目的对带有涂层修饰的柔性神经电极进行力学综合性能的评估,为电极及涂层参数的优化设计提供依据。方法对接触、植入以及微动阶段建立简化力学模型,以聚酰亚胺为电极材料,PEG为涂层材料,PDMS模具注塑法为涂层涂覆方法,设置40、80、120、...目的对带有涂层修饰的柔性神经电极进行力学综合性能的评估,为电极及涂层参数的优化设计提供依据。方法对接触、植入以及微动阶段建立简化力学模型,以聚酰亚胺为电极材料,PEG为涂层材料,PDMS模具注塑法为涂层涂覆方法,设置40、80、120、160、200μm涂层厚度梯度,对3个因素(临界载荷、最大形变、脑组织最大应变)进行综合对比评估。结果厚度增加会引起临界载荷增大、最大形变减小以及脑组织最大应变减小,同时也会导致脑组织应变区域增大。均衡3个因素考虑,选择200μm作为涂层最佳厚度,在该厚度下,临界载荷为17.9 m N,最大形变为10.1μm,脑组织最大应变为0.011 4。结论涂层厚度对神经电极的力学性能有较大影响,在具体情况下可通过设置多个力学性能因素的影响因子选择最优参数。涂层的最优参数选择可提高电极的性能,对神经电极的临床应用具有重要意义。展开更多
A compliant landing strategy for a trotting quadruped robot on unknown rough terrains based on contact force control is presented. Firstly, in order to lower the disturbance caused by the landing impact force, a landi...A compliant landing strategy for a trotting quadruped robot on unknown rough terrains based on contact force control is presented. Firstly, in order to lower the disturbance caused by the landing impact force, a landing phase is added between the swing phase and the stance phase, where the desired contact force is set as a small positive constant. Secondly, the joint torque optimization of the stance legs is formulated as a quadratic programming(QP) problem subject to equality and inequality/bound constraints. And a primal-dual dynamical system solver based on linear variational inequalities(LVI) is applied to solve this QP problem. Furthermore, based on the optimization results, a hybrid motion/force robust controller is designed to realize the tracking of the contact force, while the constraints of the stance feet landing angles are fulfilled simultaneously. Finally, the experiments are performed to validate the proposed methods.展开更多
文摘目的对带有涂层修饰的柔性神经电极进行力学综合性能的评估,为电极及涂层参数的优化设计提供依据。方法对接触、植入以及微动阶段建立简化力学模型,以聚酰亚胺为电极材料,PEG为涂层材料,PDMS模具注塑法为涂层涂覆方法,设置40、80、120、160、200μm涂层厚度梯度,对3个因素(临界载荷、最大形变、脑组织最大应变)进行综合对比评估。结果厚度增加会引起临界载荷增大、最大形变减小以及脑组织最大应变减小,同时也会导致脑组织应变区域增大。均衡3个因素考虑,选择200μm作为涂层最佳厚度,在该厚度下,临界载荷为17.9 m N,最大形变为10.1μm,脑组织最大应变为0.011 4。结论涂层厚度对神经电极的力学性能有较大影响,在具体情况下可通过设置多个力学性能因素的影响因子选择最优参数。涂层的最优参数选择可提高电极的性能,对神经电极的临床应用具有重要意义。
基金Project(61473304)supported by the National Natural Science Foundation of ChinaProject(2015AA042202)supported by Hi-tech Research and Development Program of China
文摘A compliant landing strategy for a trotting quadruped robot on unknown rough terrains based on contact force control is presented. Firstly, in order to lower the disturbance caused by the landing impact force, a landing phase is added between the swing phase and the stance phase, where the desired contact force is set as a small positive constant. Secondly, the joint torque optimization of the stance legs is formulated as a quadratic programming(QP) problem subject to equality and inequality/bound constraints. And a primal-dual dynamical system solver based on linear variational inequalities(LVI) is applied to solve this QP problem. Furthermore, based on the optimization results, a hybrid motion/force robust controller is designed to realize the tracking of the contact force, while the constraints of the stance feet landing angles are fulfilled simultaneously. Finally, the experiments are performed to validate the proposed methods.
