Wireless Autonomous Battle Bot

Projects General Guidance
1

Hi, new to the boards here.
I'm building a autonomous battle bot for a undergraduate engineering project; I'm a first time user of Arduino.

I'm part of the team building the following:
-Circuitry that takes in multiple analog signals from ultrasonic/infrared/odometer. We than take that signal, transform/amplify/move if necessary and relay that information, wirelessly, to a laptop. Also the relevant software drivers to take the wealth of information and translate/relay through the wifi modules and into the serial port.
-Circuitry that drives the various gears and motors on our bot. Again, also need the software to drive all of the motors.

So far, we've decided on the following parts:
-Arduino Uno board, central computing that interfaces with all the other modules.
-2 XBee modules, RF transmitter/receiver. One on our bot; one attached to our laptop. XBee works with the Serial Port to my understanding, so some C/Java program on the laptop will just listen on that port and do computing on incoming information. (So synchronous traffic, one way, traffic? Not too concerned, we're more worried first on making it work than it working well.)

My questions are the following:
Do we need to buy any of the Arduino Motorshields/Xbee Shields and/or kits. They're expensive and we're on a strict, strict budget. Is it feasible to do the interfacing (IE: Arduino to motor, Arduino to sensors, Arduino to XBee) wiring ourselves?
The circuitry for data acquisition from our various sensors, is their a nice Shield for that? Or will that have to be implemented by us.

Any advice would be most appreciated.

2

It will be much quicker and easier to get it working if you use standard shields for the motor drivers and so on. But if you have enough time and knowledge there's nothing to stop you from making the entire thing (including the Arduino itself) from the basic components. It's much cheaper, but don't underestimate the time and skill involved in getting it working. If you objective is to build a bot, then personally I'd rather focus my energy on the bot and not spend all my time trying to recreate a few bucks worth of circuitry.