Basic "Start Here" Robot (with Arduino)
January 13, 2012
I am brand new to robotics and I am about to try and build my first robot as a learning experience to get familiar with the basics (based on the "Start Here" design by Frits). I'll be using and Arduino Uno board instead of a Picaxe however. After reading some other posts I have come up with a list of parts and several questions. I actually have some of these parts already but wanted to sanity check that I am on the right track. I am pretty comfortable with learning the programming aspect of this but want to make sure I have a good start on the right hardware configuration. I'm a little lost when I see postings discussing use of resistors, transistors, and capacitors, but I am anxious to learn all this (and it sounds like this simple robot is a good way to get started). So here's my parts list.
1 Arduino Uno
1 Adafuit Motor Shield http://www.adafruit.com/products/81 (decided to use this vs. a breadboard with a motor chip)
1 Sharp IR sensor http://www.pololu.com/catalog/product/1136
1 Standard servo (Radio Shack) to control the IR sensor
2 DC geared motors (1:120) http://www.pololu.com/catalog/product/1121
2 Solar robotics GMPW-B Wheels (http://www.pololu.com/catalog/product/199)
Batteries and wiring for (9v or 4 AA)?
Here's a few questions:
1. I'd like to also experiment with an ultrasonic sensor (SRF-06) - http://arduino-direct.com/sunshop/index.php?l=product_detail&p=115
I did not see the SRF-05 for sale anywhere, but I assume the SRF-06 will work fine with the hardware list above?
2. I saw a post which said continuous rotation servos can also be used to drive wheels so I'd like to experiment with that as well. What are the basic pros and cons of using DC motors vs continuos servos for driving the wheels of basic robots? Do the servos give you more precise control of position? Are DC motors simpler to make work? etc.... Can you recommend a continuous servo for this application? Would this one work ok: http://www.pololu.com/catalog/product/1248 (SpringRC SM-S4303R)?
3. Since I want to control motors I assume that drives my decision to use a motor shield and that I can just use the other available pins on the motor shield (that connect to the Arduino) to connect my sensor too? Is it typically recommend (or pretty much required) to use a motor shield or a motor chip to control motors or can this also be accomplished directly with Arduino Uno? I see that there are many more advance Arduino boards but haven't gotten that far yet (maybe those are more capable for controlling motors)?
4. Is there a way to attach a sensor shield to the (ArduinoUno/MotorShield) combination for more involved projects that have more sensors?
5. Can I power all this through the external power jack with a single power source (either a 9v battery or 4 AA 1.5v batteries)? Would one be better than the other (6v or 9v)?
6. Is it possible to provide more than one power source (i.e., that would be dedicated to certain motors or sensors for example)? I'm really interested in understanding what the power options are for future projects that may have more motors and sensors (given that I am using just a single Arduino and motor shield).
Many thanks for any advice you may have to help me get started!