Teleoperation can assist people to complete various complex tasks in inaccessible or high-risk environments,in which a wearable hand exoskeleton is one of the key devices.Adequate adaptability would be available to en...Teleoperation can assist people to complete various complex tasks in inaccessible or high-risk environments,in which a wearable hand exoskeleton is one of the key devices.Adequate adaptability would be available to enable the master hand exoskeleton to capture the motion of human fingers and reproduce the contact force between the slave hand and its object.This paper presents a novel finger exoskeleton based on the cascading four-link closed-loop kinematic chain.Each finger has an independent closed-loop kinematic chain,and the angle sensors are used to obtain the finger motion including the flexion/extension and the adduction/abduction.The cable tension is changed by the servo motor to transmit the contact force to the fingers in real time.Based on the finger exoskeleton,an adaptive hand exoskeleton is consequently developed.In addition,the hand exoskeleton is tested in a master-slave system.The experiment results show that the adaptive hand exoskeleton can be worn without any mechanical constraints,and the slave hand can follow the motions of each human finger.The accuracy and the real-time capability of the force reproduction are validated.The proposed adaptive hand exoskeleton can be employed as the master hand to remotely control the humanoid five-fingered dexterous slave hand,thus,enabling the teleoperation system to complete complex dexterous manipulation tasks.展开更多
In order to overcome the drawbacks of traditional rehabilitation method,the robot-aided rehabilitation has been widely investigated for the recent years.And the hand rehabilitation robot,as one of the hot research fie...In order to overcome the drawbacks of traditional rehabilitation method,the robot-aided rehabilitation has been widely investigated for the recent years.And the hand rehabilitation robot,as one of the hot research fields,remains many challenging issues to be investigated.This paper presents a new hand exoskeleton system with some novel characteristics.Firstly,both active and passive rehabilitative motions are realized.Secondly,the device is elaborately designed and brings advantages in many aspects.For example,joint motion is accomplished by a parallelogram mechanism and high level motion control is therefore made very simple without the need of complicated kinematics.The adjustable joint limit design ensures that the actual joint angles don＇t exceed the joint range of motion（ROM） and thus the patient safety is guaranteed.This design can fit to the different patients with different joint ROM as well as to the dynamically changing ROM for individual patient.The device can also accommodate to some extent variety of hand sizes.Thirdly,the proposed control strategy simultaneously realizes the position control and force control with the motor driver which only works in force control mode.Meanwhile,the system resistance compensation is preliminary realized and the resisting force is effectively reduced.Some experiments were conducted to verify the proposed system.Experimentally collected data show that the achieved ROM is close to that of a healthy hand and the range of phalange length（ROPL） covers the size of a typical hand,satisfying the size need of regular hand rehabilitation.In order to evaluate the performance when it works as a haptic device in active mode,the equivalent moment of inertia（MOI） of the device was calculated.The results prove that the device has low inertia which is critical in order to obtain good backdrivability.The experiments also show that in the active mode the virtual interactive force is successfully feedback to the finger and the resistance is reduced by one-third;for the passive control mode,the desired trajectory is realized satisfactorily.展开更多
This paper proposes a hand exoskeleton system for evaluating hand functions. To evaluate hand functions, the hand exoskeleton system must be able to pull each finger joint, measure the finger joint angle and exerted f...This paper proposes a hand exoskeleton system for evaluating hand functions. To evaluate hand functions, the hand exoskeleton system must be able to pull each finger joint, measure the finger joint angle and exerted force on the finger simultaneously. The proposed device uses serially connected 4-bar linkage structures, which have two embedded actuators with encoders and two loadcells per finger, to move each phalanx independently and measure the finger joint angles. A modular design was used for the exoskeleton, to facilitate the removal of unnecessary modules in different experiments and improve convenience. Silicon was used on the surface of the worn part to reduce the skin irritation that results from prolonged usage. This part was also designed to be compatible with various finger thicknesses. Using the proposed hand exoskeleton system, finger independence, multi-finger synergy, and finger joint stiffness were determined in five healthy subjects. The finger movement and force data collected in the experiments were used for analyzing three hand functions based on the physical and physiological phenomena.展开更多
In this paper, the finger muscular forces were estimated and analyzed through the application of inverse dynamics-based static optimization, and a hand exoskeleton system was designed to pull the fingers and measure t...In this paper, the finger muscular forces were estimated and analyzed through the application of inverse dynamics-based static optimization, and a hand exoskeleton system was designed to pull the fingers and measure the dynamics of the hand. To solve the static optimization, a muscular model of the hand flexors was derived. The experimental protocol was devised to analyze finger flexors in order to evaluate spasticity of the clenched fingers; muscular forces were estimated while the flexed fingers were extended by the exoskeleton with external loads applied. To measure the finger joint angles, the hand exoskeleton system was designed using four-bar linkage structure and potentiometers. In addition, the external loads to the fingertips were generated by cable driven actuators and simultaneously measured by loadcells which were located at each phalanx. The ex- periments were performed with a normal person and the muscular forces estimation results were discussed with reference to the physical phenomena.展开更多
基金Supported by National Key Research and Development Program of China(Grant No.2018YFE0125600)Zhejiang Provincial Key Research,Develop-ment Program(Grant No.2021C04015)Natural Science Foundation of Zhejiang(Grant No.LZ23E050005).
文摘Teleoperation can assist people to complete various complex tasks in inaccessible or high-risk environments,in which a wearable hand exoskeleton is one of the key devices.Adequate adaptability would be available to enable the master hand exoskeleton to capture the motion of human fingers and reproduce the contact force between the slave hand and its object.This paper presents a novel finger exoskeleton based on the cascading four-link closed-loop kinematic chain.Each finger has an independent closed-loop kinematic chain,and the angle sensors are used to obtain the finger motion including the flexion/extension and the adduction/abduction.The cable tension is changed by the servo motor to transmit the contact force to the fingers in real time.Based on the finger exoskeleton,an adaptive hand exoskeleton is consequently developed.In addition,the hand exoskeleton is tested in a master-slave system.The experiment results show that the adaptive hand exoskeleton can be worn without any mechanical constraints,and the slave hand can follow the motions of each human finger.The accuracy and the real-time capability of the force reproduction are validated.The proposed adaptive hand exoskeleton can be employed as the master hand to remotely control the humanoid five-fingered dexterous slave hand,thus,enabling the teleoperation system to complete complex dexterous manipulation tasks.
基金supported by National Natural Science Foundation of China (Grant No. 50975009)
文摘In order to overcome the drawbacks of traditional rehabilitation method,the robot-aided rehabilitation has been widely investigated for the recent years.And the hand rehabilitation robot,as one of the hot research fields,remains many challenging issues to be investigated.This paper presents a new hand exoskeleton system with some novel characteristics.Firstly,both active and passive rehabilitative motions are realized.Secondly,the device is elaborately designed and brings advantages in many aspects.For example,joint motion is accomplished by a parallelogram mechanism and high level motion control is therefore made very simple without the need of complicated kinematics.The adjustable joint limit design ensures that the actual joint angles don＇t exceed the joint range of motion（ROM） and thus the patient safety is guaranteed.This design can fit to the different patients with different joint ROM as well as to the dynamically changing ROM for individual patient.The device can also accommodate to some extent variety of hand sizes.Thirdly,the proposed control strategy simultaneously realizes the position control and force control with the motor driver which only works in force control mode.Meanwhile,the system resistance compensation is preliminary realized and the resisting force is effectively reduced.Some experiments were conducted to verify the proposed system.Experimentally collected data show that the achieved ROM is close to that of a healthy hand and the range of phalange length（ROPL） covers the size of a typical hand,satisfying the size need of regular hand rehabilitation.In order to evaluate the performance when it works as a haptic device in active mode,the equivalent moment of inertia（MOI） of the device was calculated.The results prove that the device has low inertia which is critical in order to obtain good backdrivability.The experiments also show that in the active mode the virtual interactive force is successfully feedback to the finger and the resistance is reduced by one-third;for the passive control mode,the desired trajectory is realized satisfactorily.
文摘This paper proposes a hand exoskeleton system for evaluating hand functions. To evaluate hand functions, the hand exoskeleton system must be able to pull each finger joint, measure the finger joint angle and exerted force on the finger simultaneously. The proposed device uses serially connected 4-bar linkage structures, which have two embedded actuators with encoders and two loadcells per finger, to move each phalanx independently and measure the finger joint angles. A modular design was used for the exoskeleton, to facilitate the removal of unnecessary modules in different experiments and improve convenience. Silicon was used on the surface of the worn part to reduce the skin irritation that results from prolonged usage. This part was also designed to be compatible with various finger thicknesses. Using the proposed hand exoskeleton system, finger independence, multi-finger synergy, and finger joint stiffness were determined in five healthy subjects. The finger movement and force data collected in the experiments were used for analyzing three hand functions based on the physical and physiological phenomena.
文摘In this paper, the finger muscular forces were estimated and analyzed through the application of inverse dynamics-based static optimization, and a hand exoskeleton system was designed to pull the fingers and measure the dynamics of the hand. To solve the static optimization, a muscular model of the hand flexors was derived. The experimental protocol was devised to analyze finger flexors in order to evaluate spasticity of the clenched fingers; muscular forces were estimated while the flexed fingers were extended by the exoskeleton with external loads applied. To measure the finger joint angles, the hand exoskeleton system was designed using four-bar linkage structure and potentiometers. In addition, the external loads to the fingertips were generated by cable driven actuators and simultaneously measured by loadcells which were located at each phalanx. The ex- periments were performed with a normal person and the muscular forces estimation results were discussed with reference to the physical phenomena.
