Ubicomp Project | Group of 3 | Contribution: Gathering haptic specifications, Research Protocol, Hardware Prototyping, Qualitative Analysis

NASA: Wearable Haptics for Navigation

Effective navigation of astronauts on terrains where visibility is compromised

There are instances when the astronauts have to navigate extra-terrestrial surface towards the base station or to explore the surroundings. This puts a very heavy demand on their visual system to gauge the surroundings. What happens when the visibility is compromised due to sandstorms or any other such calamity? This project tries to explore the tactile display for such situations to help astronauts in directing and navigation. We are trying to find the feasibility of a specific instance on such displays i.e head mounted tactile display and comparing it with a torso belt tactile display for comfort, response time, task completion time and hausdorff distance.


This project was presented at Wearable Technology Symposium held at Johnson Space Center, NASA, Houston


Design of the Tactile Displays:
The design of the band and the placement of the motors was inspired my most sensitive points on the torso and on the head as substantiated in the research. Hardware prototyping was done to build the displays. Quick tricks were used to make the displays as modular as possible such that in the event when one of the modules broke, the others could work perfectly.



Feasibility Study:
Once the prototypes were ready, we ran 2 studies to gauge user preference, completion time and comfort level for each of the displays.

Study 1: Here the users pressed the arrow keys based on the feedback received from the tactile display. For example, if sensation of vibration came from right, users have to hit right arrow key. There were 10 participants for the study.

Study 2: Here, the partipants turned in the direction from where the vibration feedback came. This task was conducted with 5 participants.



Results:
The results from the two studies were quite contrasting. Although the participants preferred torso belt (high comfort rating), their response time was better using the head-band. They were apprehensive that head-band might cause head-aches or dizziness if used for prolonged durations.

Torso-Belt: Better Comfort
Head-Band: Better Response Time.


Conclusions and Future Directions:
Based on the results, Head-band fared better on performance and torso-belt fared better on comfort. A mixed strategy could be used to convey critical information on the head while simple information on the torso for prolonged usage. In future, more quantitative studies should be conducted to test the comfort of head-bands. Also, different vibration patterns could be studied which would more insight into what pulse frequency maximizes comfort or performance in critical and prolonged usage. Another interesting dimension is to study the threshold of the numbness of the body part to the incoming vibration-feedback


This project was presented at Wearable Technology Symposium held at Johnson Space Center, NASA, Houston