Assessment of Soft Actuators for Hand Exoskeletons: Pleated Textile Actuators and Fiber-Reinforced Silicone Actuators

Abstract

Soft robotic approaches have been trialed for rehabilitation or assistive hand exoskeletons using silicone or textile actuators because they have more tolerance for alignment with biological joints than rigid exoskeletons. Textile actuators have not been previously evaluated, and this study compares the mechanical properties of textile and silicone actuators used in hand exoskeletons. The physical dimensions, the air pressure required to achieve a full bending motion, and the forces generated at the tip of the actuator were measured and compared. The results showed that the construction method of the silicone actuators is slower than the textile actuators, but it generates better dimensional accuracy. However, the air pressure required for the actuators to generate a full bending motion is significantly lower for textile actuators, and the blocking force generated at that pressure is 35% higher in the textile actuators. There are significant differences across all variables compared, indicating that actuators constructed using pleated textile techniques have greater potential for the construction of an exoskeleton for hand rehabilitation or assistance.

SenGlove - A Modular Wearable Device To Measure Kinematic Parameters Of The Human Hand

“…A broad variety of wearable devices has been developed for the use at the human hand [3,21]. Very often the main focus is an active, actoric support of the hand with exoskeleton systems [8][9][10]12,13,22], the provision of haptic feedback [7] or non-kinematic parameters like the measurement of pressure [23,24] or the use of electromyography (EMG) [9,11,25] are examined. Especially for the use of EMG, the wearable has to be extended at least to Disclaimer/Publisher's Note: The statements, opinions, and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s).…”

“…actoric components or battery packs) bag packs [9], belts [35,36] or cuffs [7] are used. Furthermore, smart textiles or sensors [37,38] or the use of soft robotic concepts [9,12,22,35,36] are discussed in literature.…”

SenGlove - A Modular Wearable Device To Measure Kinematic Parameters Of The Human Hand

“…A broad variety of wearable devices has been developed for the the human hand to use [3,21]. Very often the main focus is on an active, actoric support of the hand with exoskeleton systems [8][9][10]12,13,22], the provision of haptic feedback [7] or nonkinematic parameters like the measurement of pressure [23,24] or the use of electromyography (EMG) [9,11,25]. Especially for the use of EMG, the wearable has to be extended at least Version February 24, 2023 submitted to Bioengineering 2 of 34 to the lower arm [25].…”

SenGlove—A Modular Wearable Device to Measure Kinematic Parameters of The Human Hand

“…A broad variety of wearable devices has been developed for the human hand to use [ 3 , 21 ]. Very often, the main focus is on an active, actoric support of the hand with exoskeleton systems [ 8 , 9 , 10 , 12 , 13 , 22 ], the provision of haptic feedback [ 7 ] or non-kinematic parameters such as the measurement of pressure [ 23 , 24 ] or the use of electromyography (EMG) [ 9 , 11 , 25 ]. Especially for the use of EMG, the wearable has to be extended at least to the lower arm [ 25 ].…”