Second set of questions:
1. Is that range in miles, kilometers, yards, meters, feet, inches or centimeters?
2. About the joystick: Simply put, digital is basically either it's on, or it's off. Analog will allow for variables, meaning it's on, off, or anywhere inbetween. For example, if you want to be able to control the speed AND direction of the bot with the joystick, then you will need to go with an analog joystick. By pushing the joystick... say... up a small amount, the bot will move forward slowly. By pushing the joystick all the way up, it will move the bot forward at full speed. With digital, if you move the joystick up, the bot will move forward at full speed. When it's not moved up, it won't move. Period. Digital is much easier though. For digital, quad-directional movement, joy-PADS are much more common. They will be easier to use and implement as well. Joysticks, for the most part, ARE analog. So, you will need to make a decision on that, and let me know. Joy-pad, analog joystick, or digital joystick (Not recommended.)?
3. What functions are the buttons needed for?
4. Are you planning to use any type of programming or semi-complicated logic circuitry?
Answer these questions for me and I'll see how I can help. Best of luck to you.
Rain