I'd like to attach some extra equipment to the iRobot. Does anyone have any idea of a weight limit before mobility is restricted or it just breaks? Could it possibly carry a few extra pounds?
My dad actually works as a a software designer for iRobot and he tells me that exceeding 15-20 lbs is probably the limit for a load with which the robot can function normally. Personally though, I would just test it out with increasing weights (if you're worried about it breaking, it is built to withstand a 180 lb guy standing on it). However, he also mentioned that with the added weight, it won't be able to accurately measure the magnitude of its acceleration so the cliff safety features (what makes it stop before it tumbles down the stairs) may not work as intended so definitely be careful about that.
Note that this question has been answered before. If you are using the iRobot Create 2, the answer is found here: What is the maximum payload weight for create 2/can I use old create accessories with the Create 2? For the original iRobot Create, the answer is here: Questions about Irobot Create