This is our company's book, published a few years back. It's written with the Texas Instruments MSP430 microcontroller in mind, but the first half of the book has pretty much everything you need to know to get started in robots.
A nice introduction to the hardware side of things (it does not cover programming). Written with the beginner in mind.
If you're new to programming or if you're new to programming microcontrollers, this is an excellent book for getting started. Arduino is the microcontroller that most hobbyists use and you can buy an Arduino microcontroller board with programming support for less than $10 - a great way to learn programming.
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