Student Projects
Contact Information
University: The University of Leeds
Team Members (with year of graduation): Fotios Athanasakis (2013) George Clarkson (2013), Daniel Lochtman (2013) & Nilesh Mistry (2013)
Faculty Advisers: Dr Brian Henson & Dr Peter Culmer
Email Address: For more information about the project please contact Nilesh Mistry mn09nm@leeds.ac.uk or leave a comment below and we will get back to you
Submission Language: English
Project Information
Title: Tactile Display to Simulate Softness and Wetness
Description: We'll ask you how soft it is and then make you feel wet. 
Products:
NI equipment
CRIO, CRIO 9215 (Analogue I/O), 9403 (Digital I/O) & 9264 (Analogue O) modules, LabVIEW Control & Simulation & FPGA toolkits & MyDAQ
Additional equipment
ZX-LD40 laser sensor & amplifier, 3 voice coil motors (VCMs), force sensor, ratiometric hall effect sensors & H-Bridge drive circuits
The Challenge
The overall challenge was to build a Tactile Display to emulate the feeling of softness and wetness and to carry out psychophysical tests on people to verify the device functionality. This was then broken down into several bitesize objectives;
1. Build aTactile Display
2. Develop a control system using LabVIEW and the National Instruments Hardware
3. Validate the performace of the device to ensure it outputs correctly
4. Carry out psychophysical tests
5. Using the results from the device, verify the device functionality
Background
What is a Tactile Display?
The sense of touch can be broken down into different perceptual quantities such as softness, roughness, temperature and wetness. Tactile displays are devices which try to emulate the different sensations. There are two main types of sensing involved in touch, kinaesthetic and cutaneous. Kinaesthetic sensing is the position in relation to other parts of the body. Cutaneous sensing involves skin receptors and its this type of sensing which detects most the different perceptual quantites.
Advantages of Tactile Displays
The advantages of such devices are limitless. For example, tactile devices have the potential to create less invasive surgeries; if the surgeon can feel the texture or softness of an organ before making a large incision, it may result in the operation not being necessary. Another area is the gaming industry to create a better virtual reality and even in the consumer industry, to feel materials online before making a purchase.
Previous Research
There have been several softness displays which have been previously created including the softness display with an active tensioner built at The University of Tokyo in Japan. This device simulated softness cutaneously to the user by varing the contact area and pressure distribution of a finger.This project uses their device as the initial starting point on which we built upon. This has been descibed in the report attached. Currently there is little reasearch on the display of softness. However it has been suggesting from previous works that its possible to display wetness through amplitude modulated waves.
The Purpose for this Project
The main purpose for this device is to provide research platform on which to build upon. From our contributions and then continual research carried out under the supervision of Dr Henson, the overall aim is to evenually lead to a device able to aid in Laparascopic surgery.
The Solution
1. The Built Tactile Display
The device was successfully built to the specifications and an image of the device is added as an attached file
2. Developed control system using LabVIEW and the National Instruments Hardware
There were two stages in creating the control system. Firstly an updated model for softness was created, then from this the final LabVIEW code was created. The updated model for softness is shown in the report attached. The full LabVIEW code has also been attached.
3. Validate the performace of the device to ensure it outputs correctly
Graphs which prove the performance of the device has been shown and explained in the report attached.
4. Carry out psychophysical tests
Psychophysical tests were carried out. A method of Triads was used to match one of two outputs from the device to a silicon block. Details about the psychophysical tests are described in the report attached.
5. Verify the device functionality using the results frompsychophysical test
Unfortunately the test carried out did not conclusively prove the functionality of the device but it did suggest there was potential. The results and more information on the psychophysical tests are shown in the report. Unfortunately the device had not been programmed to display wetness before the project was complete. Suggestions for testing the display of wetness once coded have been made in the report.
Conclusions
Summary
To sum up, a tactile display was built. An updated model for softness developed and from which a control system. Psychophysical tests were carried out. However, did not conclusively prove the functionality of the device but did suggest there was potential.
Future Research
Future work for this project can involve displaying a more realistic feeling of softness. Unfortunately we ran out of time before we had a chance to write the code for displaying wetness. We suggest testing the display of wetness by sending an amplitude modulated wave through VCM 2 and 3 consisting of two frequencies; signal 1 between 0-500Hz and a carrier signal unique to an individual, as described in the report.
Long Term Aim
Finally the longterm aim for this project and for future work carried from this is to eventually have a device ready to act as an aid in Laparoscopic surgery.
Attatched Files
1. Poster
2. Code (to be uploaded very soon)!
3. Report
Thank you for reading our work. Please feel free to leave any thoughts or comment below! 
