Xoon

Not sure how showing a CV90 with a bushmaster 50mm would change anything. The US has already tested the gun on the Bradley. And if you thinking about the recoil or similar, the CV90 is capable of fitting the Bofors 57mm gun. Source: http://www.ointres.se/projekt_strf90.htm

That's pretty comprehensive. Though, I find it weird. Do you know if Ethercat or Ethernet/IP was considered? I think it would make a lot more sense in a military application.

Thanks for taking the time to clarify. I really appreciate it.

Just curious, could you tell me how the Marder compares to the Puma, maintenance wise? Like specific examples that don't break OPSEC. Do you know if it is Ethernet, Ethernet/IP or EtherCat?

I know that the armor layout of the Strv 122 is less efficient. I was just wondering about this: I am confused here. Coli states "You can see that side armor was prioritized", referring to the hull side armor schematic. Then, you say : "It wasn't prioritized". And then you say : "The Strv 2000 should be better protected around the hull". Since the Strv 2000 should be better protected around the hull, would it not makes sense to think that the engineers prioritized side armor? I am not trying to strawman you or anything like that. It is just that your statements confuse me a little and I was wondering if you could clarify a bit.

Most common issue is that the gas has leaked out.

What part of it does not work? The cooling or heating?

I see. I wonder if it would be more cost effective. Unlocking the breaks for towing would be useful. Forgot about that one. True. I think it only would need to be big enough to capture one or two full breaking sessions from top speed.

Thank you for the correction, late night translation is not my strong suite. Good point. But one thing, doesn't the Strv 2000 have thicker sideskirts than the M1A1?

" De tekniska studierna delades upp i kompetensuppbyggande studier och försök, konceptstudier samt projektstudier. Fysiskt skydd kom att prioriteras före beväpningssystem, ledningssystem och rörlighetssystem. Tre huvudkrav kom att bli konceptstyrande: Skjutning under gång varvet runt (360º) med huvudvapnet Direktutblick för vagnchefen från vagnens högsta punkt Överlevnad för vagn och besättning vid en träff i ammunitionslagringen Vidare beaktades de typiskt svenska förhållandena som normalt resulterade i speciella krav på försvarsmaterielen – den korta värnpliktsutbildningen följd av korta repetitionsövningar (dvs materielen måste vara lätt att handha) och det faktum att materielen under större delen av sin livslängd skulle ligga i mobiliseringsförråd med ett minimum av underhåll. Skydd I projekt Strv 2000 tillmättes skyddet i vid bemärkelse stor betydelse – eller stridsvagnens överlevnadsförmåga vad avser skydd mot upptäckt-identifiering-träff, skydd mot verkan och skydd mot efterverkan. Kraven sattes mycket högt både vad gäller låga signaturer inom våglängdsområdena för IR och radar, men framförallt för det ballistiska skyddet. Dessa inkluderade mycket förutseende krav på skydd mot minor och takverkande stridsdelar. Grundprincipen för vagnens uppbyggnad var ett minimiskrov i pansarstål som var tillräckligt tjockt för att kunna ta upp krafterna vid körning och skjutning. Det skulle också kunna ta upp de krafter som en yttre skyddsmodul kunde åstadkomma då den träffats. I det fall den yttre skyddsmodulen använde sig av principen med ett spontaninitierat tungt explosivt reaktivt pansar (t ex i kompositionen 15/3/9) – effektivt inte bara mot riktad sprängverkan, utan även kinetisk energi – kunde dessa krafter på grundstrukturen bli relativt stora. De försök som gjordes mot frontalt monterade moduler med denna typ av skydd visade att det var möjligt att kraftigt störa en penetrerande pilprojektil. Tanken var också att Strv 2000 skulle använda en stor andel keram i skyddskonstruktionen. Det faktum att den totala andelen keram skulle komma att uppgå till flera ton i respektive stridsvagn gjorde att ett det så kallade Skyddskeramprojektet startade upp 1988. Under ett par års tid gjordes försök med många olika typer av keram - Al2O3(aluminiumoxid), B4C (borkarbid) och TiB2 (titanborid) – men trots ett brett deltagande från svensk industri, FOA och FMV, blev det inte så mycket mer än en medioker referenskeram. Inspirerade av den valda skyddslösningen i den amerikanska stridsvagnen M1A1 DU där Chobhampansaret uppgraderats med skikt av utarmat uran, gjordes provskjutningar i Sverige även mot denna typ av material. Resultaten visade på möjligheten att nå bättre skyddsprestanda om volymen och inte vikten var gränssättande. Stor möda lades även på att åstadkomma en från besättningen separerad ammunitionslagring som skulle tåla såväl krutbrand som en detonation efter direktträff på en RSV-stridsdel med övertändning som följd. Den lösning som utarbetades fungerade och hade stora likheter med motsvarande utrymmen i Leopard 2 och M1A1 med så kallade ”blow off panels”, men hade en utvecklad princip för att förhindra total övertändning med total utslagning som följd. Skotten var placerade längst bak i chassiet. " Translation: " The technical studies are divided up into competence building studies and trials, concept studies and project studies. Physical armor is prioritzed over weapon systems, FCS and mobility systems. Three main requirements have steered the concept: - Firing while on the movie, 360 degrees with the main weapon. - Direct sight for the vehicle commander from the tanks highest point. - Survival of the tank and crew in case of a hit to the ammunition storage. Furthermore, the typical Swedish environment is considered, which normally results in special requirements for defense materials - the short conscription followed by short repletion exercise (meaning that the material needs to be easy to handle) and the fact that the material in bigger parts of its lifetime will be located at mobilization storage with a minimum of maintenance. Armor: In project Strv 2000 is armor of the highest importance - or the tanks survival chance against discovery - identification - hit, protection against impact, after armor protection. High requirements are sett for a low signature in the visual spectrum, for IR and for radar, men but most of all the armor. These include requirements for mine protection and roof armor. The principle of the tank construction is a minimal hull of armor steel, made strong enough to absorb the force when driving and firing. It should also be able to take up the force that a outer armor module would achieve when hit. In the case of the outer armor module, the use of the principle with a spontaneously initiated heavy explosive reactive armor (composition 15/3/9) - effective not only against directed explosive force (I assume HEAT) but also kinetic energy - could these forces on the hull be reality large. It was also thought that Strv 200 would use a large amount of ceramics in the armor construction. The fact that a big portion of ceramics would come to make up several tons in the tank in question, caused the so called ceramic armor project to be started in 1988. In a couple of years time a few tests were done with several different ceramics - Al2O3(aluminium oxide), B4C (boron carbide) and TiB2 (titan boride) - but even with a board cooperation between Swedish industry, FOA and FMW, the ceramics turned out the not be much more than a mediocre reference ceramics. Inspired by the armor solution chosen by the US tank M1A1, in which the Chobham armor was upgraded with a layer of depleted uranium, a firing trial was held in Sweden against this type of material. The results showed a possibility of better armor performance if volume and not the weight was the restricting factor. A lot of effort was put into producing the ammunition storage, separated from the crew, which can take a direct hit and detonation from a ATGM. The solution developed was similar to the Leopard 2 or M1A1 with their so called "blow off panels", but was also developed to stop a chain reaction from detonating all the ammunition. The ammunition was placed in the hull rear. " I translated the section covering the armor for you guys. Though I do not see anything indicating that the front engine required longer side armor. The requirements state the coverage, regardless of a front engine. Though the coverage required is similar to the M1A2 and Leopard 2's turret. I can translate more if anyone is interested.

Why not let the motor freewheel? Simply stop powering the pump and the hydraulic liquid will flow through the system until it expends the energy and stops. Alternatively, you could "short circuit" the motors, by directing the hydraulic fluid from the outlet port to the inlet port. Variable breaking power could be accomplished with a throttle valve at the outlet port and/or feeding into a accumulator. If a constant pressure has to be provided, then this valve works like the throttle. Rotating direction can easily be changed by a cross (?) valve. Not sure what it translates into. The E-stop sounds painful. I have been trying to find a breaking method that does not require friction breaks, and can lock the wheels without using power. I think line lock would have a better service life than conventional mechanical brakes, since it does not grind away, like a friction break. I guess a locking pin would be used for parking break. A simple safety feature would be a spring-loaded valve, which is normally closed, and powered by the hydraulic pressure from the system. If hydraulic pressure drops below critical levels, the breaks engage. A second throttle valve would control breaking. For regenerative breaking, the flow would be directed into a high pressure accumulator, and out of a low pressure accumulator. A relief valve would redirect the flow once the accumulators reach a certain pressure. This pressure would then be redirected thought the pump, which would drive the generator, charging the battery. Once the battery is full, the generator makes close to zero resistance, and the flow would circulate in the system, being restricted by the throttle valve until it grinds to close to a stop, then the throttle valve closes completely, locking the line. Then the parking break would be engaged, letting go of a spring, locking the driveline with a bolt, and releasing the safety valve.

" En 10,5 cm kanon monterades ovanpå Mardern i ett enmanstorn. Med denna rigg UDES 19 genomfördes ett flertal olika försök – körning, skjutning, med mera. Det gjordes egentligen två riggar för UDES 19. Utöver kör- och skjutriggen tillverkades även en laddrigg. På dessa genomfördes kör-, skjut-, observations-och laddförsök. Laddriggen testade principen att låta en laddpendel som roterar runt samma axel som kanonen föra skotten ett och ett från magasinet till kanonen. Konstruktionen visade sig fungera bra och vara så robust att varken snö eller de grenar man testade med (upp till 5 cm) tjocka utgjorde något hinder för funktionen, däremot sågs det finnas risk att skräp följde med skotten in i kanonen. Man testade dock inte känsligheten för beskjutning. Under skjutförsök bekräftades att det gick snabbare att inrikta kanonen - detta eftersom den har lägre massa än ett vanligt torn. Dock fick riggen långa skottider som berodde på dåligt fininriktningssystem. Parallellt testades även denna princip med ovanpålagrad kanon på ett chassi till Strv 103. " Translation: " A 105mm canon was mounted on top of a Marder AFV in a one-man turret. With this rig, UDES 19 completed several different tests - driving, firing and more. It is actually two rigs for UDES 19. For driving- and shooting-rig a loading rig is added. Driving, firing, observation and loading test are done on these rigs. The loading rig is to test the principle that a loading pendulum that rotates around the same axis as the canon can feed ammunition from the magazine to the cannon. This system appeared to work well and was so robust that neither snow or branches that was tested (up to 50mm) thick made a hindrance for the system, however, there is a risk of rubbish coming with the ammunition into the cannon. Therefor, the sensitivity to firing was not tested. In the firing trials in was found that the cannon was faster at aiming, because of the lighter tower. However, the rig high aiming time was thought to be because of bad FCS. In parallel this principle was tested on a chassis of the Strv 103." Source: http://www.ointres.se/udes.htm

Translation:

The idea of the thought experiment was to not use conventional mechanical parts. So a differential would be cheating. You have a good point about the torque converter, it is pretty much dead weight. I guess the pump could have a stall speed higher than the idle rpm. Though I think heavy equipment is fundamentally different from, say a car. Since they require much higher reliability, roughness and lower cost. As far as I have seen, most hydraulic driven heavy equipment use air cooled hydraulic motors. This would be a no go for a car. A liquid cooled motor would probably deal with the overheating issue. Does your vehicle have a duty cycle? I really appreciate that you share your experience, could you tell me some more?

Thanks, I sadly do not have a lot of practical experience with hydraulics, so this was very helpful. I had a idea about a sort of hydraulic transmission. The idea was to use hydraulics instead of a mechanical reduction gear and differential, and then couple a accumulator to the system to absorb breaking power for later use. I have heard that hydraulic regenerative breaking has a efficiency of 90% compared to the electrical at around 60%. I also wonder if it is possible to completely lock the motors (assuming they are completely sealed, no run off), and use them as a low speed break/parking break. I wonder if a sort of insane diesel-electric-hydraulic parallel-series hybrid would be more efficient than a diesel-hybrid or conventional mechanical layout. I know that diesels are the most thermally efficient ICE. But a vehicle usually needs a generator and starter to power the vehicles electronics and easily start the ICE. So a motor/generator setup could be used. And since diesel need a turbocharger to make any meaningful power, a variable geometry turbocharger with a motor/generator setup could be used. A exhaust heat recovery system could also be used. This effectively makes a soft hybrid. However, even with a purely electric vehicle, a electric motor still needs a reduction gear to get the best efficiency. So I thought, what if we couple this system to a hydraulic transmission? As far as I understand hydraulics, it is still kinetic energy, so it is a alternative to a mechanical system. With this we could integrate accumulators and get more efficient regenerative breaking, and locking the hydraulic motors to hold the vehicle still. So when the vehicle starts its ICE with the motor/generator, which also powers the electrical system. To quickly accelerate it uses the motor/generator on the axle and the turbocharger to get instant acceleration and close to no turbo-lag. When cruising it uses the ICE, with assists from the electric and hydraulic system. When the vehicle breaks, the hydraulic system absorbs the energy and stores it in the accumulators, if more power is needed, the electric motor kicks in, and then the engine break. To hold the vehicle still, the hydraulic motors are locked. If the vehicle needs more power, the energy from the accumulators are transferred to the motor/generator to charge the battery. I might see if a can draw up a proper diagram if anyone is interested.

I have a curious question: Lets say I have a car and I want to power it with hydraulics. A engine is connected to a hydraulic pump via a torque converter. The hydraulic pump powers two motors that are plumbed in parallel. Would this work like a differential, or would a actual differential be needed? Also, Could I use a pump/motor setup as a reduction gear?

Honestly, I think a machete or a sami knife would be better, chops just as well in my experiance. I rarely use my hatchet. I have actually chopped down more trees with my spade than with the hatchet.

Some guy wrecked the Trump National Doral Miami Hotel lobby (NSFW): https://www.liveleak.com/view?t=kqoSt_1540401872

The biggest newspapers in Norway are complete crap for the most part. They mostly recycle articles from abroad, to the point that they don't even care to properly translate it, and instead use norwegianized English words. Most articles are about celebrities, and useless junk from abroad. Its so bad that you have to read a local newspaper to get national information. We even had "murica experts" to give people "informed opinions" on the "political landscape" in the US. Turned out most of them were no more knowledgeable than your average tourist. One popular theme is "vesle mannen" (little man) which is a piece of rock in the mountainside in the region were I live which is supposed to fall down, but it has used over 4 years already. People in the capital have literally used hours watching a rock in a remote place on the opposite side of the country. Most coverage about Canada is mostly about weed, and some about Jordan Peterson. Defense is for the most part "HA HA, look how badly the armed forces messed up in acquiring this new piece of gear", "*insert stuff about conscripts and exercises here" and "murica bought our shit". Its a a dying business after all, trying the scrape the barrel for money. Do US media have comment sections? Because they removed them here in Norway for the most part.

Norwegian media spoke with a "expert" named J. Reid Meloy. I use quotation marks since Norwegian media tends to call anyone with knowledge of a subject a "expert", though this one is actually a forensics researcher. According to him, this is probably a person with deep hate for the targets. He thinks this most likely is driven by ideology, most probably a white nationalist. He thinks the person could be military and police, because of the technical knowledge needed to build a bomb. He thinks the election is the cause. Source: https://www.aftenposten.no/verden/i/p62Ve6/De-mystiske-postbombene-i-USA-kan-vare-motivert-av-valgkampen_-mener-ekspert

Indeed they are, I watch them once in awhile for the entertainment. I feel most of his videos are of good quality, so just pick some topic you find interesting. Though I would not call the Kalergi plan unattainable. I actually think it is a genius plan, in a psychopathic genocidal way. Ethnic groups a problem? Simple replace them with a mixed of new people that don't really identify with the nation. How not to start a race war? Simply make sure the recipient country has low birth rates and make sure the sender country has high birth rates, and don't do it too quickly, death by a thousand cuts. After 100 years, the natives are a minority or gone. Then form a new national image around the new state.

If you are talking about Black Pigeon Speaks, then actually no, I just saw the title and wondered what it was, so instead of watching his video, I actually looked it up. He is a bit too propagandistic for me. Though I have to say, the 1900s were really a interesting time.

Today I learned about the Kalergi plan, which is basically a reverse nazi plan for the unification of Europe from the 1920s

The answer is simple: