Table 1 Therapist and stroke survivor design specifications and the HERO Grip Glove’s capabilities

Apply at least 10 N of extension to each finger and the thumb to enable cylindrical grasping

TBD, Applies 80 N of tension force across artificial tendons to assist extension of all fingers and the thumb. The force exerted on the fingers was not measured.

Apply at least 15 N of grip force and ideally 67 N

X, Supplies 12.7 N (SD 8.9 N) of grip force and 11.0 N (SD 4.8) of pinch force through the index and middle fingers and thumb. Larger forces can be applied if the user volitionally generates force to supplement the glove’s force.

Untethered, weighs less than 400 g, and profile less than 5 cm to avoid obstructing ADL performance

✔, Wireless, weighs 284 g (0.63 lb) in fully-operable state (with all components in Fig. 1 included), the maximum profile protrusion is 2 cm (battery case height).

Controlled by the affected hand with less than a 16% false positive rate

~, The IMU (affected hand) control mode showed a 90% grasp intent detection accuracy (10% false positive rate) during the BBT. Additional instruction was required to complete the water bottle task. Manual and automated modes were rated 3.8 and 3.4 (out of 5) for ease of use during an ADL, respectively.

Does not hyperextend affected finger joints and pressure points eliminated

TBD, No hyperextension was observed and no complaints about pain were mentioned. The pressure exerted on the fingers was not measured and the glove could obstruct observation of joint hyperextension.

Device cost less than 500 USD

✔, Components cost 300 USD, device available at cost through MakersMakingChange.com

Able to don on flexed and flaccid hands in under 5 min, ideally without assistance

~, Each user donned the glove onto their spastic (flexed) or flaccid hand in under 5 min. The glove was doffed in less than 1 min. Assistance was needed for donning but not doffing.

Enables stroke survivors with severe hand impairment to extend their fingers

✔, Increased finger extension (147^o, SD 44) and range of motion (145^o, SD 38) for each stroke survivor.

Enables stroke survivors to use their affected hand in activities of daily living

✔, Enabled each participant to successfully grasp and release blocks during the BBT and to grasp, lift, manipulate and release a water bottle, a fork and a pen. The glove’s effectiveness was rated 3.4 (out of 5).

 Length x Width

33 cm × 10 cm

 Safety Features

Screw-drive transmission to limit extension, Velcro wrist strap for doffing in less than 1 min

 Actuated ROM

Approximately 158^o for relaxed stroke hands (summed MCP-PIP-DIP bending)

 Speed of Actuation

Approximately 21^o/second (summed MCP-PIP-DIP bending)

 Battery Life

> 4 h of continuous use