My university is looking at purchasing an egg-bot for promotion of engineering on open days and such, they seem like just what we are after but i am concerned they may not be reliable enough for our needs. We have several robots and promotional things that are cursed with reliability problems. Could this thing run for 1-2 hours at a time more or less constantly without any big issues? And how prone are servos to breaking
Specifically im worried about the pen servo, in my experience tower-pro servos are incredibly prone to broken gears. I notice they are a low cost clone of the hitec hs-55, which are a much better quality servo. Does this mean if i got a hs-55 separately i could use it as a drop-in replacement to make it more robust?
The Eggbot is actually a bit overdesigned in terms of motor capacity and so forth. It can easily run all day, and we have used several units side by side, all day long, on many different occasions while giving demos or otherwise exhibiting the Eggbot. When we give demos like these, we normally don’t bring any spare parts (motors or otherwise) along.
The stepper motors are super reliable. They basically seem to last forever, with a couple of exceptions: on rare occasion one gets damaged in shipping or by dropping it on the floor such that it lands on the shaft. We’ve heard reports lately of people replacing the motors in their 3D printers with our steppers for improved performance.
The servo motor is indeed a low-cost clone of the HS-55. It’s not the lowest-end clone, nor the highest, and yes, you can use a brand-name HS-55 as a drop-in replacement. Again, if dropped correctly, it is possible to break one easily. However, we do not know of any documented cases of one wearing out or breaking during the course of normal use, either from customer reports or on our heavily-used demo units. I suspect that our use of the servo motor is just very gentle compared to how they are used in RC cars and airplanes, where they do break very easily due to repeated impacts.