The thing is, they are more than a robot vacuum. They need to be able to:
- deal with rougher, bumpier terrain (friction!)
- do so uphill through uncut grass
- not stall the mowing motor with high grass
- cover a larger area
- be waterproof against rain
All of these points need a lot more power individually, and especially so when taken together (and carrying the weight increase of all those upgrades). It seems reasonable they'd cost at least twice as much for "similar" feature/budget levels. And I think that's pretty much what we're seeing.
- deal with rougher, bumpier terrain (friction!)
- do so uphill through uncut grass
- not stall the mowing motor with high grass
- cover a larger area
- be waterproof against rain
All of these points need a lot more power individually, and especially so when taken together (and carrying the weight increase of all those upgrades). It seems reasonable they'd cost at least twice as much for "similar" feature/budget levels. And I think that's pretty much what we're seeing.