Technology: X-FAB MEMS XMB10
Dr. Ali Mohammadi, Steven Ng
Mitigating the resolution bottleneck
Assistive technologies such as Braille and swell papers have been evolved to digital tactile displays, which help the visually impaired (VI) individuals to receive graphical information through the sense of touch.
To mitigate the resolution bottleneck of existing tactile displays, we have developed a new high-resolution vibrotactile display technique following the feedback received from researchers in the Departments of Computer Science, Psychology and Education.
Developing a sensor solution
Our technique allows one electromagnetic coil to selectively vibrate multiple smaller tactile pixels (taxels) based on their mechanical resonance frequency.
We now investigate the integration of tactile sensing mechanism in the new actuator to control the vibration of tactile elements.
Thereby, we have embedded off-the-shelf piezoelectric sensors underneath the taxels to track the resonance frequency of the taxels. However, the bulky size of these sensors avoids using individual sensors especially in the high-resolution taxel configuration, whereby multiple taxels are implemented within a small area.
In this project, we have designed capacitive MEMS sensors in XFAB processes to measure the vibration of 3D printed taxels. The capacitive sensors built in XMB10 processes will measure the displacement of taxels in Z direction and supply the measured output as the feedback signal to the actuator input.
Increasing accuracy of taxel tracking
This sensor will allow the implementation of a closed-loop control system to accurately track the resonance frequency of taxels. In addition, the proposed sensor will create an interactive and bilateral communication to receive tactile input from the user.