1. Weekly Meeting 4 September 30 th, 2013

2.  Look into revolving door company ◦ Check into their patent ◦ See what they power ◦ Estimate the energy generated  Apply these principals to a turnstile September 29, 2013 2

3.  Not patented, limited data available  Made by Boon Edam of Netherlands  No batteries involved, only supercaps ◦ unknown cap size, but 60 of them  Switches between self power and grid power  Motor generator used with 2 gear ratios  http://www.boonedam.us/doorsystems/nrg- plus2-tourniket.asp http://www.boonedam.us/doorsystems/nrg- plus2-tourniket.asp September 29, 2013 2

4. Estimated gear ratio 25:2

5. September 29, 2013 2 Appears to be some large motor generator with gearing

6. September 29, 2013 2 60 supercaps, unknown size Some kind of regulator to switch on/off grid

7. Pros:  Constant current not needed  Easier to model  Safer to work with, less regulation needed  Widely available parts  Lots of selection  Higher energy density September 29, 2013 2 Cons:  Discharge is weeks, not months (still ok)  Limited voltage range 2.3-2.7V only  Cell balancing circuitry needed if multiple caps used

8.  Design prototype using bicycle gears ◦ Cheap (free) ◦ Widely available in mixed sizes ◦ Standardized size means easily compatible parts  Jordan and Andrew examined what gears are available for use on some of their bikes  Connor and Alex did more motor research to try to determine a final ratio between turnstile and motor September 29, 2013 2