A wearable skin stretch haptic feedback device: Towards improving balance control in lower limb amputees

Abstract

Abstract-Haptic feedback to lower limb amputees is essential to maximize the functionality of a prosthetic device by providing information to the user about the interaction with the environment and the position of the prostheses in space. Severed sensory pathway and the absence of connection between the prosthesis and the Central Nervous System (CNS) after lower limb amputation reduces balance control, increases visual dependency and increases risk of falls among amputees. This work describes the design of a wearable haptic feedback device for lower limb amputees using lateral skin-stretch modality intended to serve as a feedback cue during ambulation. A feedback scheme was proposed based on gait event detection for possible real-time postural adjustment. Preliminary perceptual test with healthy subjects in static condition was carried out and the results indicated over 98% accuracy in determining stimuli location around the upper leg region, suggesting good perceptibility of the delivered stimuli.

A pilot study on locomotion training via biomechanical models and a wearable haptic feedback system

“…With the motivation to increase embodiment between amputees and their prosthetic device, Battaglia et al evaluated the ability of a rotational skin-stretch haptic wearable to convey proprioceptive information of a robotic hand [25]. For lower limb amputees, Husman et al proposes the use of a lateral skin-stretch haptic wearable to cue the user of gait events during ambulation [26].…”

Latest technology in minimally invasive thoracic surgery

“…In addition, to vibration, lateral skin stretch feedback has been an area of research with promising results, by stretching the skin to stimulate mechanoreceptors, or normal skin deformation to simulate palpation for example. Small wearable devices over the finger pads, due to the high density of mechanoreceptors, are under development, and can see future application in surgery by providing more detailed and complex haptic feedback; vibrotactile illusions like pulling sensations, can be achieved through asymmetrical vibrations on the skin, or modelling for rough surfaces by using different frequencies of vibrations to stimulate the Pacinian or Meissner corpuscles for the desired textural sensations (24,25). A combination of vibrations and mechanic feedback like lateral skin stretch can enhance the feedback sensation, while additional visual input, like a dynamic force indicator or scale, can also be visualised on the display to further elucidate force and tension applied.…”

Portable haptic device for lower limb amputee gait feedback: Assessing static and dynamic perceptibility

“…The haptic plate that makes contact with the skin consists of a 3D printed array of 24 stimuli pins arranged in grid formation. An array of stimuli pins was chosen rather than a single stimulus point to maximize the area covered by the stimuli on the skin, adapting to our previous work [12]. To create the lateral movement to the skin, the haptic plate was attached to a frame driven by two miniature servo motors arranged in a rack-and-pinion mechanism as shown in Figure 1( drive signal, both servo motors will rotate to a determined angle which is translated into a linear movement of the haptic plate ( Figure 2).…”