Boston Dynamics is developing amazing tech but they are demoing robots for tasks that are better with 4 wheels. Dynamically balanced walkers inside are niche application.
Smarter robot hands and 4-wheeled robot movers are where the markets and money is. Boston dynamics may be moving towards that direction but they still like to show the cools stuff they can't find markets for.
Seems like an easily enough problem. Basically every car out there has reverse sensors...
This is a smart usage of a dead weight (batteries) that makes all the other motors smaller and lighter.
Thanks for teaching me something :)
Source - I was part of a project in college that built a recumbent tandem bike. We built the frame out of large-diameter steel tubing, and it was quite heavy. I followed it on a normal bicycle several times while testing. Even with 2 people pedaling, it was easy to keep up with going up hills. It would tend to get away from me going downhill though.
For a device leaning into shelves to grab things, being dynamically balanced might be useful. Like a racing sailboat with a movable keel or ballast. But you could do that with a three wheeled design.
I bet there's also a static version of this bot with three wheels, slightly larger footprint, where the battery pack is situated over the third wheel for leverage.
But the swinging battery pack? In theory it reduces the footprint of the bot, but any time the bot is trying to grab a package, the battery is moving. Which means you can't let another robot or human enter that space. So either you have a very very complicated calculation of what areas of the warehouse are 'empty' at any moment, or your logistics program has to treat the robot like it's its worst-case footprint at all times. At which point you might as well make it static. Right?
I had the same intuition, but then I remembered the toy I'm playing with - the spectacularly unstable 4-rotor copter that could not even take off without an onboard computer actively keeping it level all the freaking time. And it's rock solid almost no matter what.
As technology changes, our intuitions must follow.
2-wheeler is not better or more stable than 4-wheeler and requires more maintenance.
if the 4-wheeled version must also have the same level of acceleration and speed of picking up, won't it also need a counterbalancing mechanism? It just won't need the "balancing algorithm", but will need a way to balance the arm swinging out.
Also, the counterbalancing mechanism is written with software, so once perfected, it's "free" to deploy. The weight could be the actual batteries, so no added extra weight!
Do you see cars with huge counterweights?
And no, it is not free to deploy by any means. Any moving, huge, swinging parts will cause expensive problems. Remember your hard disks.
Of course it depends on the weight of what you are moving, but it doesn't seem like the 2 wheeled robots in the video can actually move "heavy" weights.
I would not call 15 Kg "heavy". I can carry that myself on a single arm...
Wheel issues (typical):
1) flat tire (if the wheel is not "solid" only)
2) axle bearing
Controller+swinging counterweight:
1) a gazillion electronic components, connectors and contacts, bearings as well, the actuator for the swinging, etc., etc.
What happens if the environment is a bit humid?
For the wheel, a little rust, for the complex electronic system?
And BTW, we can save 25% by using only three wheels ...
DARPA funding is not necessarily violent. One can argue that the current explosion in self-driving cars is due to the DARPA challenges in the 2000s.
I think they have solved 2-wheel control. Lets move on.