Help me select a microcontroller

You have a wide variety of microcontrollers.
I am a decent computer programmer but have never programmed a microcontroller.
If you could make a suggestion on which one to choose from the requirements
listed below then I would like to purchase one for controlling the rapid movement
of an omni-directional 30 lb combat robot

Requirements:
Function one)
-Input three PWM signals from a SpreadSpektrum receiver.
-Mix the input signals using basic math operations and a lookup table.
-Output four PWM signals to four speed controllers.
Function two)
-Input one additional PWM signal.
-Input from two limit switches.
-Output one PWM signal to controll the speed and direction of one motor.
-Program to reverse motor direction when a limit switch is tripped.

The microcontroller would need to process both functions at the same time.

Another microcontroller that comes to mind is the Parallax Propeller, offering 8 x 32 bit cores for demanding applications such as yours. You do have many options as indicated by Carlos.

Welcome to the RobotShop Community Forum RBARON!

You will need to provide further information about the PWM signal you are trying to read. If you are simply trying to read RC signals almost any (fast enough) microcontroller will do the job. Also, if you need to PWM output then the Arduino would be a safe bet.

Also, this thread has useful information about Reading RC signals with the Arduino: arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1204020386/156#156