材料：
L293D
文章：
http://www.geek-workshop.com/forum.php?mod=viewthread&tid=12690&highlight=������
http://www.arduino.cn/thread-1202-1-1.html
小车总体
http://playground.arduino.cc/Main/AdafruitMotorShield
画电路图工具
http://fritzing.org/projects/
串口JSON指令发送
http://www.geek-workshop.com/thread-3407-1-1.html
https://github.com/interactive-matter/aJson
http://interactive-matter.eu/how-to/ajson-arduino-json-library/