As a potentially easier alternative to TensorFlow, we decided to try out the Pixy2 camera. This camera has built-in object recognition, similar to TensorFlow, using color. The PiWars "toys" and "fish tank" can be colored objects, set inside a white arena, so identifying them should be doable.
I attached the Pixy2 PCB to the front of the Dexter robot, and plugged it into the Pi via USB. The LED on the Pixy2 turned on, and I followed the provided instructions to install the Pixy2 driver libraries and dependencies.
I tried running the provided test program, but pixy.init() failed, suggesting that the camera wasn't connected properly.
The provided PixyMon application can be used to auto-detect the USB Pixy2. I tried connecting the Pixy2 to PixyMon on my computer, and it still failed. I then tried swapping out the USB wire, and the camera connected!