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A comment on Boston Dynamics’ new robot stacks boxes [video]. Parent comment

Re:Boston Dynamics’ new robot stacks boxes [video] by HALtheWise on Friday March 29, 2019 @09:19PM (#19526936)
Interesting. I just looked more into this, and it seems to depend on what performance regime we are measuring speed in. It seems like recumbants are always heavier, which makes them worse on hills, but extremely optimized recumbants with aerodynamic shells are lower drag on flat ground. From an agility perspective, uprights always win, which is probably the closer analogy for "cycle speed" that Handle cares about.

Thanks for teaching me something :)

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Re:Boston Dynamics’ new robot stacks boxes [video] by ufmace on Sunday March 31, 2019 @06:31PM (#19538854)
Basically right, except for one detail: Heavier recumbent bikes are slower to get up hills, due to being heavier. But that extra weight actually makes them faster going downhill. Not enough to be faster overall if the power source is still one person pedaling, but still.

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.

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Re:Boston Dynamics’ new robot stacks boxes [video] by eeZah7Ux on Sunday March 31, 2019 @08:42AM (#19535293)
The main difference is that on an upright bike one cannot exert more force on the pedals that the body weight, while on a recumbent the upper body is locked into the chair and pushes against the back.
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Re:Boston Dynamics’ new robot stacks boxes [video] by ufmace on Sunday March 31, 2019 @06:33PM (#19538867)
Not true. It's a completely standard technique to pull down on the handlebars to exert more force than your body weight on the pedals. Watch any video of a pro cyclist climbing hills, or sprinting on a straight.
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