Hello, I'm Yuhu Liu, from the University of Tokyo, Japan.
I will start the presentation about Thermocaress: A Wearable Haptic Device with Illusory Moving
Thermal Stimulation. Haptic presentation technology has been developed
to improve the immersion of VR or as a tool for remote communication.
Thermal sensation is often involved in human-human contact.
To recreate this temperature, many Peltier-based thermal devices have been developed.
Liquid-based thermal devices have also been developed to pursue soft contact and high-speed
temperature presentation. Contact is often followed by movement.
It is neuroscientifically known that we innately feel a sense of pleasantness when our arms
are gently stroked. It is also known that stroking at a temperature
of human skin enhances pleasantness. To exploit this effect in engineering, various
approaches have been made to create stroke sensation.
However, simply combining both temperature and stroke devices would make the device too
large. It is known as Thermal Referral that when
thermal and tactile stimuli are applied to two nearby points on the skin, temperature
can be felt in both areas. In our study, we proposed a hypothesis that
if the tactile stimulus site moves, the transferred temperature site will move together.
Based on this hypothesis, we implemented a prototype ThermoCaress.
The temperature is presented by flowing water through the pouch.
The moving tactile sensation is presented by continuously inflating five pneumatic pouches.
Each pneumatic pouch is equipped with a microblower and a driver circuit.
Therefore, the complex pneumatic system required in conventional pneumatic devices could be
simplified in our device. Since the soft device adheres to the skin,
it is expected to be able to enhance the thermal conductivity.
To test our hypothesis about the illusion of thermal movement, we conducted a user test.
We also investigated the effect of the conditions of the temperature, such as presenting position,
size, and degree of temperature. Additionally, we examined the effect of thermal
moving illusion on the pleasantness of the stroke.
Experimental conditions are here. Please pause the video or see our paper for
more detailed information. After the stimuli were presented, the participants
replayed the position of the temperature they felt by moving two fingers.
They also answered the pleasantness of each stimulus on a Likert scale of -3 to 3.
This is the result about the distance of thermal movement.
The results confirmed our hypothesis that it is possible to create thermal moving illusion
by overlapping a pressure stroke on a fixed position of temperature stimulus.
It was also indicated that the position, size and the presented temperature did not affect
the sense of temperature movement. This is the result of the pleasantness.
The main result was that cold stimuli felt good.
This is a surprising result compared to the previous research in the field of neuroscience,
which showed that strokes at the temperature of human skin were the most pleasant.
When we feel something, various factors and contexts come into play.
Perhaps the fact that the experiment was conducted in the summer affected the results.
One of the current issues with ThermoCaress is the water system.
In the current implementation, water is stored in a bucket, but since the amount of water
actually used is small, we believe that a small plastic bottle-sized tank can be used
instead. In this way, the control circuit and water
tank can be placed in a shoulder pouch, and ThermoCaress can be used portable.
As a future prospect, we would like to explore the possibility of using ThermoCaress as a
communication device by testing it in an environment close to real life.
Here is the summary of the presentation. Thank you for watching.