Haptic Vest 2.0

The Haptic Vest 2.0 is a wearable vest that uses a front-facing depth camera and an array of 128 vibration motors to let its wearer "feel" an image of the obstacles in front of him, and their individual distance. It is part of our BMBF-funded project Personal Photonics.

What does it feel like?

Imagine putting on the Haptic Vest (it's more of a tight-fitting, broad belt across your lower chest, actually), closing your eyes, and starting to walk. As you approach a lamp post that you are in danger of running into with your right shoulder, you start feeling a vertical column of motors vibrating on the right half of the vest. As you get closer, the vibration gets stronger and shifts further towards the right. You make a small left turn to correct your course, the vibrating column moves off the array of motors to your right, and you are safely on your way without risk of running into the post.

How does it work?

The Haptic Vest is based on earlier work at our lab by David Antón Sánchez' OpenVNAVI: A Vibrotactile Navigation Aid for the Visually Impaired.

It uses combined I2C-PWM expander boards with driver circuits for the vibration motors. These boards use a pinheader at the side for crimped connections to the motors and to each other (via I2C) as well as the battery.

Motors, wiring, and PCBs are held in place with orange 3D-printed plastic clips. The battery and Up board for processing are also enclosed in a 3D-printed housing.

Files for both PCBs and 3D-printed parts can be found on github. All 3D-printed parts for connecting electronics with the textile are designed to be printable without support structures.

To make the vest, a basic layout is cut into a textile layer (a prefabricted vest or waist belt). Our sample pattern is in the github archive. Each vibration motor (5 mm diameter, 8 mm length, with encapsulated excenter) is clipped onto the fabric using our 3D-printed motor housings. Standard wires are used to connect them with the driver PCB on each size. Crimped connectors allow for an easy exchange of faulty motors.

The wires are held in place on the fabric using additional 3D-printed clips. Each PCB gets its own power line to the battery on the back, to reduce current stress on the wire, while the I2C lines are bundled at each side and connected to the Up board.

The Up board serves as the brain for controlling the motors. For the case, we use a design we found online. A Realsense depth camera is connected to the board via USB 3.0, attached either in the middle of the vibration motor matrix with 3D-printed connectors (for zero optical parallax error), or elsewhere on the user's clothing.

A more detailed description is in the works.

Created by thar. Last Modification: Monday 24 of July, 2017 18:25:41 by borchers.

Media Computing Group at RWTH Aachen