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Comment by jstrieb | Hacker News Reader

I question the benefit of any jumping robot that is designed for continuous hops if there is no evidence that it can land.

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I'm honestly surprised about how much interest there has been in a landing controller. I always thought it was a bit less interesting than getting the robot bouncing around doing new things.

I could see how being able to stop gracefully could be useful in some scenarios, but there are some other jumping tasks in the queue before I work on that.

Rather than working on the perfect landing I think a good enough landing would be sufficient (crash and get back into ready to jump posture). Mostly so that the scenario of back to back jumps can be tested (which would also be interesting for stress testing). I'd love to watch the wall jump over and over until the robot breaks/stops for example.

Edit: I see something similar is mentioned in future research. Cool :)

Rather than working on the perfect landing I think a good enough landing would be sufficient (crash and get back into ready to jump posture).

That's been done a few times. The first time was a mobile land mine developed at Sandia. It was a ball with a fuel-powered piston for jumping. After each jump, it used an interior weight to get itself positioned and aimed for the next jump. The plan was to drop a bunch of these from aircraft into enemy territory. When one of them detected a good target, like a convoy, all the mines nearby would converge on the target and blow it up.[1]

There's also this small fence-jumping, tracked robot from 2009.[2] Landing is uncontrolled, but it can survive crash landings and run upside down, so that doesn't matter too much.

[1] http://www.sandia.gov/LabNews/LN10-20-00/hop_story.html [2] https://www.youtube.com/watch?v=NjANAebfs6Q

I'm honestly surprised that you're surprised - it's hard to judge what makes the problem difficult if you don't include landing. There's lots of ways to get something to 'jump' (like these toys [1]) that aren't too useful.

This isn't meant to be a criticism of your work, but an explanation of the impression it made in me. If it had been presented as "here's a new approach to jumping with these advantages", I'd have been impressed. Billing it as "the most agile jumping robot ever" while not being able to land it is setting your audience up for disappointment. My touchstone for jumping robots is that Boston Dynamics robot that can jump onto a building, and then I saw yours needing safety nets to jump a meter - you just don't want to set me up for that comparison. On the other hand, your video did get me excited to see where you go in the next few years - I definitely do want to see chain jumps exectued, even in controlled evironments.

[1] https://s-media-cache-ak0.pinimg.com/originals/2e/87/10/2e87...

OK, I see where you're coming from. The sandflea is a very practical, application-driven platform, and our robot is just a simple scientific tool meant to test new ideas about jumping. We were interested in the science of the new modes of locomotion so there wasn't much value in developing the landing for this work. We'll try to stick the landing next time.

That would certainly be fun to see! Make sure it ends up on HN again when you've got some more cool stuff to show us.

That makes more sense; I, too originally read the post with a different type of robot in mind. After re-watching the video and re-reading the article (and of course reading these HN discussions), I'm appreciating Salto more for what it is: an excellent example of well-engineered biomimicry with a lot of potential for future robots.

Just for reference, here is a video of the mention Boston Dynamics robot: https://www.youtube.com/watch?v=6b4ZZQkcNEo

Really cool.

by all means, please keep doing what you're doing. it's impressive work.

> I'm honestly surprised about how much interest there has been in a landing controller.

This is probably the most textbook example of hyperfocus I've ever seen since I was a teenager and kept jumping higher and higher until one day I hit my head on the ceiling!

That's targeted for future research. From the end of the article:

"You've probably noticed that Salto doesn't have a lot of sensing on it right now, and its jumping skills are all open-loop. In order to orient itself, it uses a rotary inertial tail, but it's not (yet) able to adapt to different surfaces on its own.

The next things that the researchers will be working on include investigating new modes of locomotion, and of course chaining together multiple jumps, perhaps with integrated sensing."

But that's the more challenging (and thus more impressive) part of it. I haven't spent any time in researching "jumping" and I'm sure this jumping robot is impressive to those in the know, but as a layman, this is like a self-driving car minus the self part.

Engineering is a discipline of taking a problem you cannot solve, breaking it into component problems that you figure out how to solve.

Consider too the publication this research appeared in. Science Robotics is concerned with the scientific underpinnings of robotics, which in this case was the new ideas about how robots can jump.

I could slap an off the shelf stereo SLAM system on the robot, but that's just solving an integration problem instead of doing the science.

Yes, a robot that can jump on top of a building in 1 jump sounds more useful to me, something like this one: https://www.youtube.com/watch?v=6b4ZZQkcNEo&t=0m14s .

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