Loss of hand function severely impacts the independence people with spinal cord injuries (SCI) between C5 and C7. To achieve limited grasps or strengthen grip around small objects, these individuals commonly employ a compensatory technique to passively induce finger flexion by extending their wrist. Passive body-powered devices using wrist-driven actuation have been developed assist this function, in addition advancements active robotic aimed at articulation for dexterous manipulation....

This paper presents the design of a motor-augmented wrist-driven orthosis (MWDO) for improved grasp articulation people with C6-C7 spinal cord injuries. Based on traditional passive, orthotic (WDO) mechanism, MWDO allows both body-powered and motorized actuation grasping output thus enabling more flexible dexterous operation. Here, associated control scheme enables active decoupling wrist finger articulation, which can be useful during certain phases manipulation tasks. An additional...

Despite the broad utility of grasp taxonomies to describe manual abilities, no such tool exists for people with spinal cord injury (SCI). This leaves gaps in practical assessment assistive devices and tools that SCI might use during dexterous manipulation. Here, we evaluate strategies employed by individuals C5-7 using six publicly available videos develop a preliminary taxonomy. The taxonomy was then evaluated completeness an egocentric video case study author C5-6 SCI, captured while...

Wrist-driven orthotics have been designed to assist people with C6-7 spinal cord injury, however, the kinematic constraint imposed by such a control strategy can impede mobility and lead abnormal body motion. This study characterizes compensation using novel Tenodesis Grasp Emulator, an adaptor orthotic that allows for investigation of tenodesis grasping in subjects unimpaired hand function. Subjects perform series grasp-and-release tasks order compare normal (test control) constrained...

Assistive orthotics have the potential to augment grasping capabilities of individuals with limited hand functionality. People a cervical-level spinal cord injury (SCI) lack direct control semi-flaccid, curled fingers on both hands, which often precludes independent donning and doffing orthotics, thus limiting their use in daily life. This paper presents novel orthotic designed improve functionality while facilitating for cervical SCI: Single-size Semi-soft Mitten (SSAM). device utilizes...

Spinal cord injuries (SCI) substantially affect sensory, motor, and autonomous functions below the level of injury, reducing independence quality life for affected individuals. Specifically, people with SCI between C5 C7 cervical levels encounter limitations in voluntary finger wrist flexion, grasp capability. Compensatory strategies like tenodesis grasp, whereby extension passively closes fingers, remain; this is effective lighter objects but insufficient heavier ones. Typically, wearable...

Despite the broad utility of grasp taxonomies to describe manual abilities, no such tool exists for people with spinal cord injury (SCI). This leaves gaps in practical assessment assistive devices and tools that SCI might use during dexterous manipulation. Here, we evaluate strategies employed by individuals C5-7 using six publicly available videos develop a preliminary taxonomy. The taxonomy was then evaluated completeness an egocentric video case study author C5-6 SCI, captured while...

Spinal cord injuries (SCI) substantially affect sensory, motor, and autonomous functions below the level of injury, reducing independence quality life for affected individuals. Specifically, people with SCI between C5 C7 cervical levels encounter limitations in voluntary finger wrist flexion, grasp capability. Compensatory strategies like tenodesis grasp, whereby extension passively closes fingers, remain; this is effective small light objects but insufficient heavier ones. Typically,...

Spinal cord injuries (SCI) substantially affect sensory, motor, and autonomous functions below the level of injury, reducing independence quality life for affected individuals. Specifically, people with SCI between C5 C7 cervical levels encounter limitations in voluntary finger wrist flexion, grasp capability. Compensatory strategies like tenodesis grasp, whereby extension passively closes fingers, remain; this is effective small light objects but insufficient heavier ones. Typically,...

Abstract Assistive device design classes are popular and often incorporate local community members in projects as stakeholders, or need-knowers. It remains important to generate best practices improve student-stakeholder interactions these service-based classes, particularly those that focus on the early product stages like need-finding feels-like prototyping. This study is performed across two offerings of new class "Augmenting Human Dexterity" at University California Berkeley; it serves a...

Without finger function, people with C5-7 spinal cord injury (SCI) regularly utilize wrist extension to passively close the fingers and thumb together for grasping. Wearable assistive grasping devices often focus on this familiar wrist-driven technique provide additional support amplify grasp force. Despite recent research advances in modernizing these tools, SCI abandon such wearable long term. We suspect that constraints imposed by generate undesirable reach kinematics. Here we show using...

Body-powered upper-limb prostheses remain a popular option for those with limb absence due to their passive nature. These devices typically feature constant transmission ratio between the forces input by user and grasp output prosthetic gripper. Work incorporating continuously variable transmissions into robotic hands has demonstrated number of benefits in terms motion forces. In this work, we use custom prosthesis emulator evaluate viability applying body-powered context. With haptics test...

Wrist-driven orthotics have been designed to assist people with C6-7 spinal cord injury, however, the kinematic constraint imposed by such a control strategy can impede mobility and lead abnormal body motion. This study characterizes compensation using novel Tenodesis Grasp Emulator, an adaptor orthotic that allows for investigation of tenodesis grasping in subjects unimpaired hand function. Subjects perform series grasp-and-release tasks order compare normal (test control) constrained...

For those with upper limb absence, body-powered prostheses continue to be popular for many activities despite being an old technology; these devices can provide both inherent haptic feedback and mechanical robustness. Yet, they also result in strain fatigue. Body-powered prosthetic graspers typically consist of a simple lever providing relatively constant transmission ratio between the input forces from user's shoulder harness grip force their prehensor. In field robotic hand design, new...

Individuals with neurological impairment, particularly those cervical level spinal cord injuries (SCI), often have difficulty daily tasks due to triceps weakness or total loss of function. More demanding tasks, such as sit-skiing, may be rendered impossible their extreme strength demands. Design exoskeletons that address this issue by providing supplemental in arm extension is an active field research but commercial devices are not yet available for use. Most current designs employ electric...