xxiii■ CONTENTSDallas Personal Robotics Group Roborama ........................................................................................ 425Central Illinois Robotics Club .............................................................................................................. 425Chicago Area Robotics Group (Chibots) .............................................................................................. 425The Great Wide Open .................................................................................................... 425
■ Appendix A: Appendix A .................................................................................... 427
Magical Ohm’s Law ...................................................................................................... 427
Ohm’s Law is Helpful in Selecting a Current-Limiting Resistor .......................................................... 428Help in Determining Current from a Voltage ....................................................................................... 428The Key Point of Ohm’s Law ............................................................................................................... 429The Larger Implication of Ohm’s Law ................................................................................................. 429Things I’ve Accidentally Destroyed While Writing This Book ........................................ 430
Which Way Does a 9 V Battery Get Installed? ..................................................................................... 430Melting Switches ................................................................................................................................ 430Popping Multimeter Fuses .................................................................................................................. 431Fool Me, Twice .................................................................................................................................... 432Voltage’s Real Name .................................................................................................... 432
Ground, Not Negative Voltage ............................................................................................................. 433V Double Letter ................................................................................................................................... 433■ Appendix B: Appendix B .................................................................................... 435
Getting Into 3D Printing ................................................................................................ 435
Leaping Not Very Far .......................................................................................................................... 436Rapidly Improving ............................................................................................................................... 437Printing the Motor Coupler ........................................................................................... 437
Designing the Model ........................................................................................................................... 438Preparing to Print ............................................................................................................................... 441Printing in 3D ...................................................................................................................................... 441Finishing the Coupler .......................................................................................................................... 442Printing a 3D Wheel ...................................................................................................... 443
Treading Lightly .................................................................................................................................. 444Compromising with a Hybrid Wheel ................................................................................................... 445