Design Engineering
Showcase 2020

Heatwaves are becoming more frequent and the world is heating up. We all want to feel more comfortable and our instinct is to turn to Air Conditioners (AC) to cool down.

However, ACs are a fundamental part of the problem and continuing to use them will force us deeper into a vicious cycle of heating up the world around us. What if we could change our perception of the temperature around us, rather than changing the temperature of the environment itself?

The Saiga wearable changes our perception of the temperature in two ways. First, it provides cooling by conduction onto specific locations on the neck. Second, it allows the wearer to breathe cold air when they need a boost of relief from the temperature. Both of these techniques have been validated as effective ways to change our perception of temperature and improve our thermal comfort in hot spaces.

We developed an aesthetic prototype of our final design with three key features in mind. Firstly, specific locations on the neck are cooled by conduction, providing a refreshing and cooling feeling. Secondly, as air is inhaled through the mouthpiece, the body is cooled from the inside out. Finally, the device is activated when sweat is detected, allowing it to work in harmony with the body.

We brought these two ideas together into a working prototype that uses Peltier chips to provide the cooling to the neck, and a phase change material to cool the air for breathing.

Cooling air to 10°C proved to be very challenging, but on the other hand, the Peltier system was easy to control, gave a strong level of sensation and was able to run at a time-averaged power of under 2W making it a very low power approach to cooling people down.

We began with a varied set of experiments looking into personal cooling systems that would cool just the person, rather than the whole environment around them. What stood out to us were the approaches that changed a person’s perception of temperature, rather than actually cooling them down. The two most notable of these were localised cooling on the skin and breathing cold air. Through further experiments, we were able to find that cooling the back and sides of the neck at 25°C and breathing cold air at 10°C provided the highest change in perception and improvement in thermal comfort. We validated through final experiments with 10 participants.