I have always felt that one of the limitations of hobby robotics, has been a lack of agreement on a “standard platform” to allow sharing experiences and sharing software.
I have three battery operated robots. They eat, sleep, and eat some more - that tells the whole story.
Except for the part where we discuss them eating batteries. GoPiGo3 robot Carl is the winner in the battery eating contest. He eats eight NiMH batteries at a cost of $24 about once a year, and gets about 8 hour playtimes when the cells are new.
Next up is GoPiGo3 robot Dave. Dave eats a $35 Li-ion battery about once every three years, and gets 3 to 6 hour playtimes depending on how much he is allowed to localize and navigate.
Then there is TurtleBot5 robot WaLI. WaLI eats $40 or $58 batteries every three months, (or $100 battery once a year), and gets 2.5 or 4 hour playtimes on the cheaper batteries.
(Right now, due to the “big, cheap” battery failing to charge unexpectedly, WaLI is using his very first battery that lasted 20 months and 1691 cycles before I started playing with cheaper batteries. This old battery is still allowing 1.0 hour playtimes till the next battery arrives.)
Interestingly, his maker iRobot has been showing his battery as “Out Of Stock” for over a year.
Three robots just “Stayin’ Alive” - each with a different journey.
The important point is that all the robots are still there and are, (hopefully), still providing joy.
I am working with Charlie and Charlene, and beginning to make some progress on my projects with some programming help from ChatGPT. It’s a good partnership. I give projects substance and direction and the chat-bot helps fill in the cracks. It has a tendency to create solutions that are unnecessarily complex and I have to simplify them, but it’s working so far.
The runtime spread makes sense as a mix of pack chemistry, capacity, and how hard navigation and localization load the motors and compute. Before replacing packs, I’d log voltage under load and runtime a few times; that’s a cheap way to separate a tired pack from a charger or connector problem. For the NiMH robot, checking that the charger isn’t cooking one cell in the series could also explain the yearly replacement. The out-of-stock OEM battery is a good argument for documenting connector and voltage specs so a safe third-party option can be found.