NROVER HARDWARE

Wide Angle Camera Addon Lens

Most cellphone cameras have a very narrow field of view, making it difficult to see where you are going.  Seiko sells neat little magnetic expansion lenses for cellphone cameras allowing you to stick a little metal ring to your phone, which the magnets in the lens can then snap firmly onto.  This pretty much doubles the visible field of view.

Kyosho Blizzard RC Platform

I have played around with cars and several other platforms before settling on the Kyosho Blizzard.   This thing can go through puddles, brambles, bushes, snow, rain,  etc and has plenty of room for mounting our equipment — in fact the cover could have been custom designed it protects our phone so well and gives us such a good view of things.

I have made a few modifications to the standard platform:

• Electronic speed controller (mechanical speed controller it comes with is awful)
• 4200mAh battery (BIG battery, should be able to go for hours and hours)
• Cellphone Mount (rubber-bands to attach) on top of the battery

Bluetooth Servo Controller

Design:

This is essentially a bluetooth-to-serial adapter hooked up to a serial servo controller board.  Any bluetooth-to-serial adapter should work; the Mini-SSC II we are using has a very simple command set, where 8 60hz PWM signals can drive up to 8 standard hobby servos or speed controllers.  This allows the phone to make a bluetooth connection, then send a command (which actually looks something like FF0080 or FF0180 — it always starts with FF, then has the servo number, then a position (in hex) from 0-255 which corresponds to the range of motion of the servo.

Design goals were to have something very lightweight(every gram counts!), that could run off the 5-6v provided by the Electronic Speed Controller (or a battery pack), but could control enough servos in responsive enough a fashion with minimal latency.

Components:

• A7 Engineering’s EB501 BlueTooth serial port (~5v)

• Scott Edwards Electronics (SEEtron) Mini-SSC II Serial Servo Controller Board (~9-12v)

• Battery Doubler 12 voltage doubler board (Allows everything to run off one power supply)

Future Designs and Special Concerns:

It would be really nice if we could have a bluetooth servo-and-sensor board, with a custom micro that allowed us not just PWM output but also some nice external sensors (including ability to talk to sensors, i.e. A-D and PWM inputs) and use the same bluetooth connection to send that sensor data back to the phone.