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Darpa Literally Reinvented the Wheel for Army Combat Vehicles

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Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#211

Post by evgen »

isk517 wrote: post #205
evgen wrote: post #164

Earlier quoted context omitted.

Infrequently. The US were early proponents of combined arms tactics. Find heavy armour? Call in artillery or air support -- one of the advantages of owning the airspace over the battlefield. Oh, and the only Tiger tanks that got close to Moscow are the captured ones on display at Kubinka.

The US Shermans were equipped with cannons that had weaker armor penetration by design so that they could fire more potent high energy rounds that would take out infantry since they were expect to meet very little tank resistance. I think part of the 5:1 myth is from the fact that out of a platoon of 5 Shermans only 1 would be equipped with a gun that could penetrate a Tiger from the front.

Correct. US pre-war tank doctrine was that enemy armor should be taken out with AT guns and dedicated tank destroyers (e.g. M10 & M36) while the Shermans were infantry support and to create and take advantage of breakthroughs to flank the enemy or take out supply and ammo depots. For US units all tanks in the platoon of four tended to be the same, but UK tank corps that had Sherman Fireflys available (a Sherman with a British 17 lb gun stuffed into the turret) would often run one Firefly per platoon since the 17 lb gun could engage and destroy at range any German tank it encountered. This was why the longer barrel on the Firefly tank was often camouflaged to look like a short 75/76mm gun to reduce the chance that it would be identified and targeted.

Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#212

Post by loco5niner »

anchpop wrote: post #174
edem wrote: post #127

Earlier quoted context omitted.

What does zoot mean in this context? I'm not a native speaker.

I'm a native speaker and I've never heard it. I assume it means something like "cool fancy flashy tech"

Another native speaker (Northwest USA). Never heard of it either. I assume the same.

Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#213

Post by rimliu »

smsm42 wrote: post #208
rimliu wrote: post #120

Earlier quoted context omitted.

I still can understand the dislike HN has for this wonderful book. But given generally anti-user stance maybe I do understand it a little. Edit: "anti-user" may be to harsh. Let's say "developers first, users second".

That's pretty much the diametrical opposite of the book's message, at least in my reading of it. Most of the book has been spent, as I remember it, decrying features that look cool for developers but useless for the users, such as overly-complex configuration panels, or interfaces that emphasize "cool" features at the expense of reliable basic function, etc.

Yes, you are absolutely right about the book's message.

That was not what I was talking about. I was talking about HN attitude toward that book and HN attitude in general regarding the position wrt users/developers. Crowd here are happy to cry about user hostility because of the walled gardens, closed source, whatever, but given a choice many will go the path of the least resistance and choose the technologies and approaches that make it easier to have some kind of result without much consideration about UX or accessibility of said result. Fast and cheep to develop is winning agains enjoyable to use. Sure, it is not 100% true, but the trend is quite obvious, imho.

In case anyone here thinks I was not long enough on HN to criticise it: I've been here for the 9 years now.

Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#214

Post by lsc »

mcguire wrote: post #193
pasta wrote: post #161

Earlier quoted context omitted.

Today's cars are so much more complex than old cars. Yet almost all of them are much more reliable than old cars. I don't think simple == reliable. A wheel made of solid wood is very simple. But the choice of material is poor. So there are a lot more factors involved to make something reliable. Getting stuck in the dirt might be more dangerous than a wheel with 1000 parts that gets you out of a nasty situation. Also:…

One major difference, reliability-wise, of modern vehicles is electronic engine management---electronic fuel injection, electronic ignition, etc. These are, in fact, much simpler than their previous mechanical counterparts. Materials are better, as are engineering, but those are a wash complexity-wise. The major complexity increase has been antilock braking/traction control/stability control, all of which are (I hope…

Eh, if we want to look at mechanical complexity increasing reliability, I'd point at exhaust valves. Have you owned a vehicle with valves you had to adjust? man, life was different before hydraulic lifters. Adding a fancy complex part means I don't have to fiddle about adjusting my valves every so often. (except on my motorcycle... Perhaps BMW of the '90s thought adjusting your valves built character or something.) And valve timing has gotten a lot more complex during my lifetime, at least last time I looked, was mechanical/analog. I came of age as VVT-I/VTECH variable valve timing was hitting the mass market, and I'm pretty sure those systems were not electronically actuated. (I can't say I really have looked at this sort of thing in the last decade, so they might be electronically actuated now) I'm sure there's a bunch of other mechanical bits that got both more complex and more reliable.

I do like the example of fuel injectors vs. carburetors. The carburetors were a lot more mechanically complex, and quite difficult for a non-expert to get right. Fuel injectors are easy. a good example of just how much a simple micro-controller can make a system seem a lot more simple.

Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#215

Post by asfdsfggtfd »

mcguire wrote: post #187
asfdsfggtfd wrote: post #130

Earlier quoted context omitted.

What does them being male have to do with anything? Are you implying that being male means that they must be reckless? Or that if they were female they would automatically be careful and gentle? Careful throwing around those negative stereotypes. EDIT: The driver is likely to be getting shot at. This is going to be an order of magnitude more important than slight gender differences.

Note: the driver is unlikely to get shot at. Combat is actually rare.

Being shot is the most important time. This is when the wheel is going to be put under the most stress and it is most important that it performs...

Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#216

Post by asfdsfggtfd »

psergeant wrote: post #149
asfdsfggtfd wrote: post #137

Earlier quoted context omitted.

But there are millions of young males in the US alone who are more careful than millions of young females. The effects of testosterone are far from as simple as you suggest. It tends to lead to higher competitiveness. This is not quite the same as recklessness. Meanwhile during normal usage the driver (of whatever gender) is likely to be getting shot at. This will tend to have a larger affect than their gender.

> there are millions of young males in the US alone who are more careful than millions of young females Yes, and millions of young men in the US who are shorter than millions of young women. What’s your point? Young men are still disproportionately more likely to be in road traffic accidents. Re testosterone, the keywords you should be searching for are “risk taking behaviour”. I’m curious also what percentage of tim…

Being shot is the most important time. This is when the wheel is going to be put under the most stress and it is most important that it performs...

Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#217

Post by kbutler »

dsfyu404ed wrote: post #203
kbutler wrote: post #186

Earlier quoted context omitted.

I looked for statistics on maintenance cost of equipment for male vs female operators but didn't find any, just the un-documented assertions in https://www.equipmentworld.com/men-vs-women-who-are-the-bett... that basically say women are easier on equipment and specifically Attention to detail “I’ve always been impressed by how women take care of their machines” Smith says. “They keep them clean and don’t leave trash…

>I looked for statistics on maintenance cost of equipment for male vs female operators but didn't find any, just the un-documented assertions Ok, well my undocumented assertion is roughly the opposite. Where does that leave us? >I'd be happy to look at any statistics you can provide that show "equally hard on things". Post on /r/mechanicadvice, dump out the 80% that were written by someone who's never actually turned…

> Where does that leave us?

I guess it leaves us at, "Statistically, three times as many young adult male drivers have fatal accidents than equivalent young female drivers, despite having a smaller population."

Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#218

Post by antpls »

avip wrote: post #117
killjoywashere wrote: post #82

As a military officer, I pray these never make it past Test and Evaluation. They took essentially one part and turned it into 1000 parts. Anyone who has seen what 20 year old Marines do with these machines, let alone what happens in war, will appreciate that this is a fantastically horrible idea in a war zone. I need high reliability, not high zoot. Let NASA have high zoot.

That concept was historically referred in IDF as "The best part in a machine is the one that does not exist". It's also extremely applicable to SW.

"IDF"? "SW"?

Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#219

Post by haloux »

godelmachine wrote: post #99
haloux wrote: post #97

Earlier quoted context omitted.

20 year olds vary. As a 20 year old in the military, I was elbows deep in the B-61 Mod 10 replacing radioisotopic thermoelectric generators. Concession: id be damned if I told you that we didn’t goose the new guy bending over the explosives from time to time.

I Googled for "B-61 Mod 10 replacing radioisotopic thermoelectric generators" and I got this → https://en.wikipedia.org/wiki/B61_nuclear_bomb and upon further searching, this → https://en.wikipedia.org/wiki/Thermoelectric_generator I need to ask if thermoelectric generator was a part of the B61 nuclear bomb? Please explain.

Yes. Almost all of our nukes have some size/sort of RTG. What else do you want to know?

Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#220

Post by kchr »

RangerScience wrote: post #104
killjoywashere wrote: post #82

As a military officer, I pray these never make it past Test and Evaluation. They took essentially one part and turned it into 1000 parts. Anyone who has seen what 20 year old Marines do with these machines, let alone what happens in war, will appreciate that this is a fantastically horrible idea in a war zone. I need high reliability, not high zoot. Let NASA have high zoot.

I have never heard this use of the word "zoot" and would like know more.

Fanciness, probably derived from Zoot suits as commented elsewhere in the thread.
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