One nice thing to mention thats not clearly noticed in many pages is the communication settings between an Arduino board and an XBee running at 115.200 bps.
Initially with testing I was not able to get the communication working with speeds higher then 38.400 bps. For some reason above this speed packets are not received by the Arduino board. After some searching trough the manual I found a small note in the manual that setting the XBee speed (Command BD) to value 7 (115.200 bps) would actually run the interface speed at 111.111 bps. If you match your Arduino to talk at 111.111 bps it then works fine.

When adding an C328R camera to the rover it makes it very intresting. To control the camera you need another serial port on the ATmega328 thats not available. To resolve this use the newsoftserial class. It allows you to create a new serial port on digital IO pins. Connect the camera as below

Using the C328R camera library you can controll the camera and capture an image from it. Due to the timing issues with higher baud rates you might be limited to 57600 max. I've created a small VB 2010 program that send an asci 'c' to the arduino. It will then init the camera and send the capture command. When the camera returns the data it will call an sub that will forward the data to the serial interface.

Below is the sample beta program with an sample picture shot. As you see, in the program its still up side down, it still needs to be rotated.

Visual Basic 2010 example program fsRobot.rar (41,60 kb)

Arduino 00-18 example sketch sketch_dfrobot_1.rar (1,35 kb)

When you want to play with the arduino chip you might consider some usefull toy. The tank rover from Robotshop will give you a platform to play with. With the complete set you get:

• pcb with ATmega328 chip
• frame for holding tank tracks
• battery holder
• Tamiya gearbox and tank tracks
• 2 XBee modules
• 1 usb adapter for the XBee module
• 1 XBee shield to put on top of the rover
• Solarcharger shield to put on top of the rover
• LIPO battery

The basic assembly of the gearbox and tracks is pretty simpel but does require some attention. Dont forget to look at the manual if your still following the right way os assembling it

Altough there is no supplied manual and the manual online is very limited you should be able to assemble the tracks, the frame on the pcb and the gearbox. All put together you should be able to test basic functions of the rover. Download the arduino development software and connect the rover using USB. When asked for an driver look in a subdirectory of arduino software for the driver. By default its programmed to send out the values of the temp and light sensor on board. The 6 bright blue lights make it look very nice in the dark, only pitty it cannot be controlled from the program but only manual by a jumper on board.

Second step should be add the solarshield and XBee shield. First install the XBee on the XBee shield and the second XBee on the USB adapter. Make sure you set the jumpers on the XBee shield to XBee instead of USB else the XBee will not recieve the text from the chip but the USB port would be. By default the XBee modules are set for transparent mode at 9600 baud so it should work right away.