Sensors!

While thinking about how to mount my ultrasonic transducer onto the chassis I started thinking about other sensors that I would like to use and an actual purpose for the robot. To start with I wanted the robot just to be able to do basic collision avoidance. As such would a single ultrasonic sensor be enough? Should I mount it to a servo motor so it could pan, or should I buy a number of the sensors? Would I just want ultrasonics or should I investigate IR (Infra red) as well.

I decided as the Seeedstudio sensors were relatively cheap I'd buy a few more along with a Sharp IR sensor. I also needed some kind of mounting bracket. Active Robots had a range of brackets, but as with most things on the internet I had no idea what they would actually be like once I received them. I decided on sampling a few types.

• Lynxmotion MPSH-01 Multi-purpose Bracket
• Active Robots UB1S3 Bracket (All Sharp IR and Devantech Ultrasonics)
• Active Robots SPB1S3 Panning Bracket

The Sharp GP2Y0A21YK IR sensor mounted perfectly on the UB1S3 bracket as advertised, however the Seeedstuido Ultrasonic module was a close fit to the panning bracket but not a perfect fit (Nothing a needle file couldn't handle). 

In the end I mashed all the brackets into one to provide a suitable mounting point for 3 x Ultrasonic sensors angled 45 degrees apart and a forward facing IR sensor. 

I knocked up a quick breakout board to enable the sensors to easily connect with the Arduino and test them all.