You can run ROS on the RPi. If your hardware is all custom, then you'll probably have to spend some time learning how to write ROS nodes to read sensor values and publish them, and also to listen on topics to desired actuator positions and command the servos. And you'll probably want to learn some OpenCV to interact with the camera. All of this is doable. It depends on your goals, though. There is sizeable amount of off-the-shelf code in ROS for dealing with navigation. If your robot does not move, then you might be getting less out of ROS than otherwise.
That said, the main benefit to ROS is the ability to decouple the various pieces of code controlling your robot through ROS's loosely-coupled messaging framework. There is a sizeable learning curve, though, so you have to invest some time before you see the benefits.