A vibrotactile feedback approach to posture guidance

Abstract

In this paper, we explore the use of vibrotactile haptic feedback to improve performance of a sensory-motor task. Our specific application is seated posture guidance. Poor sitting postures, over time, can lead to health concerns such as low back pain. We propose a real-time haptic feedback system that actively senses and guides a person to a desired posture. We have instrumented an ergonomic office chair with a simple system using 7 force-sensitive resistors (FSRs) for posture detection and 6 vibrotactile actuators ("tactors") for haptic feedback. When the chair detects that the subject is not sitting in the desired posture, one or more tactors will vibrate, directing the subject towards or away from a certain position. In a pilot study of 10 subjects (age 23.9±1.45, weight 71.1±13.6kg, height 175±11.2cm), 100% sat in the reference posture (upright) more often when there was haptic feedback than when there was not. Additionally, when haptic feedback was temporarily disabled without the subject's knowledge, all of the subjects continued to sit in upright or near-upright postures. These findings suggest that vibrotactile feedback can be an effective means of communicating musculoskeletal commands to the human sensory-motor system, especially for motor training and rehabilitation.

Encoded sewing soft textile robots

“…We can also increase the pressure to generate higher force in the premise of no breakdown with the actuators or incorporate a variable stiffness mechanism (42) to increase the working stiffness. From another point of view, even if the force or stiffness of the wearable devices are not enough for applications like rehabilitation and posture correction, they can also act as force feedback devices to warn and guide the wearer to a desired posture (7,43).…”

[D71] Periodic Vibrotactile Guidance

“…Good application candidates for haptic channel are those which require modest information transmission and consider the other limitations. Tactile Displays are unidirectional physical interfaces that employ vibrations [166,180], tapping [6], twisting or stretching of the skin [98], compressing of the skin, and indentation to convey messages to users [118]. Unlike the force-feedback displays, tactile displays are not necessarily collocated with the input device and need not be grounded.…”

PostureCare – Towards a novel system for posture monitoring and guidance

“…In contrast to Zheng and Morrell [2010] or Mutlu et al [2007] our goal is not to exactly classify the sitting postures depicted in Figure 1, since a reliable classification requires additional sensors which for example are able to detect the curvature of the spine. Our goal was to develop an affordable sensor concept which in turn can be simply applied to any common office chair.…”

“…Another approach is to trigger users periodically to perform an exercise, where the users can use a regular office-chair. Zheng and Morrell [2010] propose an ergonomic chair which guides office workers to sit in a pre-defined position by providing a vibrotactile feedback. Force sensors placed on the sitting support as well as on the back rest of the chair are used to compute a feedback signal by using small vibration actuators.…”