It's a bicycle, also it's a boat, also it's a camper.
One off concept vehicle for now, but you can pre-order one for 18.000€, which I can't tell if it's expensive for a bike, or like reasonable for an amphibious vehicle, or pretty good for a camper.
Here's a look at it by some youtuber
I cross the border on this and immediatly 3 different police jurisdictions get into a shootout over what kind of licenses I need to operate this thing. I am taunting them the whole way by riding in shallow water, further complicating the situation.
Man I want one.
Hey if you are going by that digital drive bikes video, the video maker himself said he might have estimated the losses incorrectly due to regen braking and downhill grades which would recharge the battery a bit.
However, the video maker also lists that battery plus digital drive brings the efficiency back up to be on par with chain/belt and gear systems. The uses for digital drive bikes he lists would likely be city commuter bikes, bike rental fleets, and especially cargo bikes - where the increased weight and reduced range are less important. Of course it is harder to fine tune a motor controller versus a chain and sprocket.
I wouldn't mind getting my hands on a DD bike to test it out for myself though.
I wouldn't but that would be entirely for the gizmo-factor
I'm not and it matters little - you're not beating 95% drivetrain efficiency except in the rare case where these things would be used nigh-exlusively like one of those coal elevators that run by themselves where you only have heavy people riding them downhill and lighter people riding them uphill.
You can slap a battery on a chain- or belt-driven bike and get even further
Okay, you could pedal while standing still to charge it up - at least on a cargo bike (and there is one that does this, albeit the name escapes me atm) but then you're still just using effort to convert into energy with more losses. The physics just don't work out.
Honestly if you're going for like rugged ass shit (and fuck the riding experience because it's only for short trips anyhow, i.e. rentals), I say RETVRN to prop shaft bicycles. Now those would be intensily hard to break. But I don't even think this is much of an actual problem, most bicycle rental companies have figured this out via a closed chain guard box and some farings and that's really not the part that usually gets dinged up or willfully destroyed
This comes closest to real world application imo, but that's more on the ground of loopholing regulations so you can still claim it's a bicycle instead of like an EV that would require licensing, taxes, registration or any such thing - which I'm not against- but then you still have decades of chain-driven recumbents and such to look at to figure out how to include one of those. It's not like "slightly longer bicycle chain and some pulleys" is really a hard engineering problem to solve