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Comment Re:Why use Bizarre when they really mean Difficult (Score 1) 43

Yeah, try to drive one of those in the sort of lava fields we have here, it'd bottom out before it even gets started. ;) Even on less extreme terrain, its clearance looks like a pretty big flaw - it can hardly drive on a flat slope without nearly bottoming out, let alone uneven terrain. They could raise the center, but then they'd also be raising the CG because not on the driver but the batteries are in that center bit, and on an offroader you really want a low CG.

Seems to me the solution is to put the batteries next to the hub motors. Something right next to the hub should never bottom out, and as they're low so the CG will stay low. It also allows you to reduce or eliminate your in-arm power wiring (esp. good given all of the bending that goes on in those swing arms), thus reducing wire mass, wire cost, and wire resistance. If you fully eliminate the in-arm power wiring you'd have to charge the packs individually, but even if you retain it you could reduce it to smaller wires that only need to be able to handle charging currents and inter-pack charge balancing, not peak discharge currents. Having the batteries next to the hub motors, you could upgrade them to pretty much whatever power level you wanted.

Another problem I see is with the use of hub motors. Everyone loves them until they start messing around with them and then the problems start to become clear. One, they're unsprung mass, which reduces your ride quality. Two, they're harder to cool, which limits performance. And three, you shake them to bits even on normal roads, let alone offroad. I'd prefer each wheel being hooked up to a small high power motor, connected to the wheels via a stubby CV joint (which should lose only a fraction of a percent of the energy transmitted). That way you keep your unsprung mass low, your motors are easy to cool, and they're not shaken to bits.

This thing is underpowered, but with some proper design choices there's really no limit to how high powered it could become.

The last issue I see is, if you're making an offroader, do you really want motors and wiring connections somewhere that they're going to get wet? Do you want to have your wheel drop into a deep puddle and suddenly short out? It seems to be that they really should have the motors (and as per above, battery packs) protected by a cowling. For transmitting the power to outside of the cowling I see two options. One is to use a waterproof rotary joint, like submarines use, although those are somewhat lossy. A better option might be to have the rotor simply penetrate the cowling (with only a small clearance around it) and use your pack / battery air-cooling system to maintain sufficient positive pressure inside to resist water influx - around 5-10 PSI should be enough for unbridged river crossings, while only 1-2PSI would be needed if you only want to be able to handle the occasional puddle. The air ingress to the cooling system would need to be located as high as possible, of course, whatever design one chooses.

(Yeah, this is something I've been thinking about for quite a while, I'd love to build my own go-anywhere electric vehicle some day ;) )

Comment Re:Does anyone remember... (Score 3, Interesting) 177

Sometimes their "philanthropy" is self-serving. Paul Allen is currently in my country with his huge-arse luxury yacht with its two helicopters and two submarines, parked not at the harbour because his boat is too big, but just sitting out in the bay blocking the view. But because he explores shipwrecks and the like (something that he does for fun), it's called charity, and he gets welcome to park his floating palace at no cost.

Comment Re:Anti-Tesla Rhetoric! (Score 3, Informative) 375

What I find most annoying about all this is less the could of smug, and more the fact that household electricity use is such a small slice of the pie of overall US energy use. From wind power to this DC nonsense, it's obsessing on feelgood measures of little importance to the big picture.

This biggest slice of the pie is industrial energy use where electricity isn't part of the picture: "Primary energy use" by heavy industry for blast furnaces and the like. Industrial electricity use is the next biggest slice, followed by IIRC industrial transportation.

Comment Re:One time pad (Score 1) 125

Because then your compression function effectively becomes your encryption function. And it wasn't designed for security.

Keep in mind these are simple issues to identify and exploit. All these "what-if" scenarios have been played out repeatedly, which is why the standard response is always "use a proven secure algorithm, don't roll your own cryptographic solution." It's easier, less bug prone,and the security has been analyzed by more qualified people than you can afford. Any known weaknesses have already been identified and fixed.

Comment Re:Why children should NOT be taught to code (Score 1) 116

People that already know how to code test out of COBOL. The syntax is butt simple and being an introductory course the coding is also simple.

It's directed at the students that use salary surveys to pick majors. We are doing them a favor by showing them the worst CS environment early.

"The number of Unix installations has grown to 10, with more expected." -- The Unix Programmer's Manual, 2nd Edition, June, 1972

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