1. ME 340 Project – David Christensen and Vance Murray – March 31, 2010 Application of Heat Transfer to Ensure Product Safety on a Prosthetic Device for Finger Amputees

2. ME 340 Project – David Christensen and Vance Murray – March 31, 2010 Introduction A prosthetic device is being made for finger amputees as a part of a BYU capstone project. During user testing, the user mentioned the possibility of using the device to pull things out of the oven after they have cooked. In order to determine if that would be safe, we have conducted both analytical and physical tests. Video

3. ME 340 Project – David Christensen and Vance Murray – March 31, 2010 Problem Set-Up Find Temperature of the surface of the device near her hand over time Given T oven = T pan,i = 350˚ F T device,I = T∞ = 69 ˚ F After heating the pan to a temperature of 350˚ F, the device was used to remove the pan from the oven. A thermocouple was used to measure the temperature at one location near her hand over an interval of one minute.

4. ME 340 Project – David Christensen and Vance Murray – March 31, 2010 Results Experimental Solution Time (seconds)T surface (˚F) 072 1072 2072 3072 4073 5073 6074 Results

5. ME 340 Project – David Christensen and Vance Murray – March 31, 2010 Results Analytical Solution Results According to our model, in would take almost four minutes to reach a dangerous temperature. Set-up Lumped capacitance method was used to test the time it would take to cause harm (T = 120 ˚ F) if the pan stayed at a constant temperature of 350 ˚ F (pan on stove).

6. ME 340 Project – David Christensen and Vance Murray – March 31, 2010 Conclusions The device seems suited to safely handle the thermal conditions that would be required to pull something out of the oven. However, proper care must be taken to allow some cooling at the tip before touching the device with the user’s other hand. Also, care must be taken to ensure the hot item is tightly secured by the device.

7. ME 340 Project – David Christensen and Vance Murray – March 31, 2010 Appendix Additional CalculationsAdditional Pictures Calculations of the device modeled as a fin with steady state conditions