What do you guys think of Arduino? I have been using to build little autonomous robots and it seems to work pretty well other than storage and voltage limitations. Is there anything better i could upgrade to or should i just stick with it?
Arduino is good as a robotic controller. It has a lot of I/O ports for that kind of work. The difficulty is the development and downloading of code. In order to fix that, some folks have done projects using a combination of arduino and raspberry-pi. The Pi can be programmed directly and then be connected to the arduino to send it commands.
In a sense, you'd use the arduino for low-level robotics and the Pi for higher level robotics. The two together provide a very powerful platform for robotic control applications.
Arduino and Raspberry Pi are versatile little critters, useful for much more. Even hackers use them, but I won't discuss that. WiFi connectivity brings options for storage. For powering higher voltage servos and motors you'd just use controllers that can connect to them but handle more power with power transistors or SCRs, with a separate power source for that load.
Arduino is not very user friendly when it comes to controlling multiple servos or reading sensors. The Pololu Maestro Controller can control up to 24 servos and be programmed in C# in Visual Studio through the USB port. Each servo/sensor has three pins on the board : positive,negative, and signal. The Arduino has it's pins all over the place. If a controller requires a unique company created IDE don't waste your time. The Maestro Controller is made for common programming languages.
This board in the link has 6 ports for servos,inputs, and outputs.