Altrail Vest, stay cool and hydrated while trail running.
Trail running is a sport that consists of running and hiking over trails. Trail running often takes place on mountainous terrains. Many trails are in the open with very little shade to keep the body cool. Altrail Vest is a way to keep the athlete cool while also supplying drinking water.
Altrail Vest circulates cold water through a custom-designed vest with integrated heat exchange tubes. Cold water is loaded into a 3-liter reservoir attached to the vest's back and circulated by a pump powered by an onboard battery. The flow speed of the pump can be adjusted with high granularity to achieve fine cooling outputs. The pump flow rate is set by PD control that uses skin temperature sensors as feedback. The temperature of the water in the reservoir is monitored by a thermal resistor located in the reservoir. When the water in the reservoir rises above a preset temperature, the vest alerts the user that the cooling capacity is compromised by activating a vibrating motor and flashing a warning on the onboard LCD screen. During normal operation, the LCD screen displays the reservoir's water temperature and skin temperature. By default, the LCD backlight is off unless a button is pressed to conserve battery life. There is a detachable drinking tube that can connect to the water supply to drink from.
Inside Altrail Vest
How it works
An LCD is located at the bottom of the vest. The LCD displays the temperature of the water in the reservoir and the person's skin temperature. When the water temperature in the reservoir reaches a certain level, a warning will be set off, alerting the wearer by blinking the LCD screen on and off and turning on the vibration motor.
To control the pump, feedback from the skin temperature, a temperature sensor is used. A variation of PID control determines the pump output. The water flow increases when the skin temperature is getting too high to allow for faster cooling throughout the vest.
Warning, temerperature too high
Reservoir and skin temperature readings
Hardware Block Diagram
Collaborators: Jason Webster and Kevin Eve