> if a battery runs out, it would hit my computer.
So? It's a vacuum, you could drive it right in to a computer non-stop until the battery runs out and it's not going to do any meaningful damage. The worst case scenario would be if you had a case where the power or reset button was right there at vacuum height, but other than that what's your concern?
You'd be surprised. I have a Botvac and that thing can easily damage plenty of things in my house.
On that note, I love my Botvac. My biggest complaint though is that it has to "learn" a room first, without any sort of helping functionality. This is a problem in my eyes because the Botvac comes with an awesome in-app barrier system where you can tell it to avoid areas, but to tell it to avoid areas it has to have done a normal scan of that area.
It's a chicken-egg scenario. I can't keep the botvac out of my fragile areas without first letting it in my fragile areas.
Once scanned though, the Botvac's "no go" lines are awesome, and very accurate in my experience.
> you could drive it right in to a computer non-stop until the battery runs out and it's not going to do any meaningful damage
What is this based on (i.e., are HDDs and all the smaller components commonly designed to withstand such shocks)?
Now I've looked up a random WD Blue HDD data sheet [1], which mentions 30G shock (read/write, 2 ms). If a vacuum cleaner was to hit it directly while moving at about 1 m/s (less than 4 km/h, and it seems to walk at around that speed, though I haven't found exact values), and assuming that it would accelerate the HDD to its own speed in those 2 ms (maybe it's not realistic, though not obvious to me), that'd be about 50G (1 m/s / 0.002 s / 9.8). Even if it is so, a vacuum cleaner has a plastic bumper, a computer case is heavy, and a vacuum won't hit any of those components directly, but it seems dangerously close and I'd rather not hit the computer.
> accelerate the HDD to its own speed in those 2 ms (maybe it's not realistic, though not obvious to me)
You need to conserve the momentum and kinetic energy, so assuming an elastic collision you're going to accelerate the PC to about half the speed of roomba[1] so you're looking at closer to 25G. With the plastic bumper, you're not getting anywhere near an elastic collision and your contact time is probably a lot longer than .002 due to the deflection. I would not worry too much about this.
Three things you should keep in mind regarding those numbers:
1. They're worst case numbers, as in the hard drive being mounted perpendicular to the impact force. Some OEM crapbox PCs may have spinning rust mounted to the front of the case directly in a vertical orientation, but most PCs have them mounted horizontally and many use shock absorbing rubber bushings.
2. As noted, your numbers also assume an inelastic collision. Almost all PC cases have a plastic front, and all robo-vacs I'm aware of have the same.
3. The absolute peak potential impact force is significantly less than a single accidental kick or kid/pet running in to it.
If you're really concerned about impact, you should get your PC off the floor. That said, I'd happily frisbee a Roomba at my PC and not be concerned for anything other than the front panel of the case itself.
So? It's a vacuum, you could drive it right in to a computer non-stop until the battery runs out and it's not going to do any meaningful damage. The worst case scenario would be if you had a case where the power or reset button was right there at vacuum height, but other than that what's your concern?