Blog #4 Week of Oct 25

Since the last post, Team 20 has completed the installation of the main system components into the chair. This includes installing the copper pipe in the seat and back cushions and installing the power supply, radiator, thermoelectric module, both pumps and the main electronic components onto the bottom of the chair. The raw setup is shown in Figure 1. Some preliminary tests have been done to show we can validate the design. This includes measuring the chair movements including tilt, swivel, and lift to ensure the new components don’t impede these movements. Also, testing the surface temperature with the infrared laser thermometer has shown the chair surface can drop to a range between 15[C] - 25[C] during cooling and easily past 70[C] when heating for 15 minutes. We conducted some tests using a thermal imaging camera as seen in Figure 2. The images were of a 10 x 15 [cm^2] area at the center back of the seat cushion. The images in Figures 3 - 7 show the surface temperature of the seat, respectively: initially in the ambient environment, after 15 minutes of cooling, after 10 minutes with someone seated and the system idle, after 10 minutes with someone seated and the system cooling, and after 15 minutes of heating.

At this point in the semester, our team is thoroughly satisfied with the progress we have made, and plan to finish within the next 1-2 weeks. We are currently improving the layout design by shifting some components around and installing the already built housing for the electronic components as well as building an insulated housing for the thermoelectric device and its pump. Future plans include more testing of the surface temperature over time during cooling and heating. Also, the plan is to install insulation surrounding the soft tubing, thermocouples, temperature cutoff regulators, switches, and light indicators.