The Prototype Development Of The Wearable Lower-Lime Locomotion Assistance Robot

With the rapid development of science and technology,the exoskeleton robots,as a human-machine integrative device,have shown wide application prospects in bio-medicine,military and civil fields,which makes the research of exoskeleton robots has much more value.Considering different users and situations,the exoskeleton robots can be divided into three types of applications.The first one is locomotion assistance that is aimed at paralyzed patients who have completely lost motion and sensor ability.The second one is gait rehabilitation,which is used to help patients with mobility disorders recover their muscle strength and do the gait training.The third one is strength augmentation,which is targeted at enhancing the physical abilities of human and reducing the injuries.In this paper,a new type of wearable exoskeleton robot is designed,which can be used to help patients' motion and gait training.The main contents involve its mechanical structure and the design of its control system,and then the further research has been done through combining the theoretical analysis and motion simulation.The details are as follows.Firstly,the current research status of exoskeleton robot is summarized,including its advantages and disadvantages.According to the characteristics of human motion,its operation principle has been analyzed,and then a new type of hybrid exoskeleton robot which is combined with serial and parallel mechanism is proposed considering the disadvantages of current mechanisms.Its overall structure design is accomplished.The hip joint has two freedoms,which can achieve walk straight and sideways.The knee joint has one freedom that can achieve flexion and extension.The ankle joint has three freedoms,which contains flexion and dorsiflexion,inversion and eversion,internal and external,and these motions are actively actuated by motors,which can has high stability and large workspace.Secondly,the concrete mechanical structure of each joint is designed.Among them,the design of hip joint is innovative,which can achieve the abduction and adduction by one linear actuator.It also has more compact structure and can save money as well.And then some 0T3 R parallel mechanisms are obtained based on thePOC(Position and Orientation Characteristics)set theory.According to the characteristics of ankle joint,the most suitable one is selected.Thirdly,kinematics analysis and simulation validation of the exoskeleton robot are carried out.The overall forward kinematics is analyzed based on D-H method and,especially,the inverse kinematics of the ankle joint is also accomplished in accordance with ADAMS which has verified the correctness of the inverse kinematics model and the rationality of the mechanism at the same time.Finally,the three-dimensional model of the prototype is finished by SolidWorks,and the corresponding parts are selected including the actuators and motors.Meanwhile their usage methods are clarified which lays a solid foundation for the gait test.