Suspension Systems

[pugwash]

I am very unlikely to be knocking that up anytime soon, unless me numbers come up on Lotto!!

no fear, my "frog" is now almost finished.

i've come up with a few names for it in the same vein; the Sloth, fatty, the Rhino, Hippomobile

you get the idea

[will_warne]

The one that won Ladoga was the Frog and it supposedly cost $1m:

It is a nice peice of kit. Lots and lots of problems with this kind of setup but, if you can over come them, the vehicle could be epic.

My version: Initial designs complete, scale drawings finished July '07, build starts August '07. ~100" wheelbase, 18" of travel at each corner & fully adjustable, 4 wheel steer, skid steer, CTIS, Porche flat 6 power. Target weight 1500 kgs ready to roll with drivers and kit

[FridgeFreezer]

It is a nice peice of kit. Lots and lots of problems with this kind of setup but, if you can over come them, the vehicle could be epic.

What sort of setup is it though, Will? All we really know is that the wheels are on army-things and move independently, and that it has a conventional engine tucked in there somewhere. The actual driveline technology is the real killer as there are any number of ways of doing it.

It's amazing what shows up when you quote someone's post, nicely tucked away in white text Will

My version: Initial designs complete, scale drawings finished July '07, build starts August '07. ~100" wheelbase, 18" of travel at each corner & fully adjustable, 4 wheel steer, skid steer, CTIS, Porche flat 6 power. Target weight 1500 kgs ready to roll with drivers and kit

[will_warne]

What sort of setup is it though, Will? All we really know is that the wheels are on army-things and move independently, and that it has a conventional engine tucked in there somewhere. The actual driveline technology is the real killer as there are any number of ways of doing it.

It's amazing what shows up when you quote someone's post, nicely tucked away in white text Will

Never seen vapour text, JU??? I say no more for now.

[bill van snorkle]

I know nuffink - Jez might know a bit but it is all fairly mysterious, they're not about to give away any info about it, those are spy shots taken by one of the Finnish perverts at Vippsky Les and TBH even looking at them closely I can't work out how most of it works.

I'm guessing there may be chain drives to the rear wheels, god knows what to the front, no idea what may pass for a transfer box. You can see some sort of airbag on the suspension but but there must be more to it... All the buttons in the cab to control it are marked with things like "rocket boosters" "ejector seat" "missiles" etc. to keep people guessing

I think anyone who HAS worked it out is going to keep bloody quiet while they (try to) build their own. There have been various theories about how it works but nowt that makes you go "Aaaah, of course!" just possibilities that seem semi-likely but difficult to make work. I know it spent a lot of time on a trailer between stages at Ladoga, either through genuine mechanical failure or because it's somehow allergic to tarmac.

I am a little surprised that from the scores of mechanically minded folk who had a hand in building and prepping other trucks for Lagoda, very few have worked out what makes that thing tick.

Bill.

[FridgeFreezer]

The trouble is, for an enfeebled mind like mine, there are many ways it could work but all of them have stumbling blocks. Apparently there were quite a few hydrostatic drive vehicles on the start line but none of them actually made it much further than that. I think he was about the only thing there, working, that wasn't on "normal" beam axles of some description.

[muddy]

To me that just looks like telehandle 'axles' on air and could easily be skid steer, the engine can be mounted anyway aslong as it will drive the pump, in our manitou for instance the engine is mounted transversly and then has a ickle' prop goin to a mahoosive hydraulic pump, steering could be very similer to a hauglands bv206 with its steering wheel setup, and think how strong telehandle axles are-monstertrucks use them B)

And if it did cost $1 million then you'd think you would put a half decent exhaust on

Could be well wrong tho

[bill van snorkle]

Perhaps the transport sections should be included as part of the overall course, and penalty points added for rigs that don't complete particular stages. I'm all for innovative engineering but if such vehicles are incapable of being driven for reasonable distances at satisfactory speeds with a degree of safety then they go against the spirit of what I thought a multi purpose cross country should be.

Bill.

[will_warne]

Perhaps the transport sections should be included as part of the overall course, and penalty points added for rigs that don't complete particular stages. I'm all for innovative engineering but if such vehicles are incapable of being driven for reasonable distances at satisfactory speeds with a degree of safety then they go against the spirit of what I thought a multi purpose cross country should be.

Bill.

I'd agree Bill. Although I've only been able to look at photos of the vehicle I'd guess that its chain drive with a common shaft driving the sprockets for the front and rear arms (hence one of the reasons for the arm offset) with a diff of some description in the centre. I guess on road the windup would cause the chains to stretch and increase the chance of breakage on the stages. Not ideal but it would be a light, compact setup that'd be fairly straight forward to fabricate.

[FridgeFreezer]

Having watched the video I can confirm it's not skid steer, the front wheels turn on hydro rams hence the angle the front arms are at to give turning clearance. vehicles are supposed to drive the transit stages unless they are undergoing repairs, from what Jez has said the frog seemed to be undergoing repairs on every transit stage - whether this was true, either through a high servicing schedule on the vehicle to keep it working or through a lot of stuff wearing out quickly due to the design, is unknown. There was a rumor that the rules may be tightened this year for that reason.

[bill van snorkle]

I'd agree Bill. Although I've only been able to look at photos of the vehicle I'd guess that its chain drive with a common shaft driving the sprockets for the front and rear arms (hence one of the reasons for the arm offset) with a diff of some description in the centre. I guess on road the windup would cause the chains to stretch and increase the chance of breakage on the stages. Not ideal but it would be a light, compact setup that'd be fairly straight forward to fabricate.

What you described Will appears to be a variation on the''H''drive transmission concept used on Daimler Ferret armored scout cars as well as Alvis 6x6 miltary vehicles. ie, a single differential and cross axle behind the gearbox. on each end of the crossaxle was a '' T'' shaped bevel gearbox with driveshafts running for and aft to a 90 degree bevel gearbox that drove each wheel. The Alvis's had a NoSpin (Detroit locker) in the single differential, but I believe the Ferrets had an open diff, and a suspension system with very little articulation, so weren't very capable, but with modern hydraulic or pneumatic struts interconnected front to rear and a selectable difflock could be greatly improved.

I am getting the feeling of de ja vu. Have we covered this subject previously?

Bill.

[will_warne]

What you described Will appears to be a variation on the''H''drive transmission concept used on Daimler Ferret armored scout cars as well as Alvis 6x6 miltary vehicles. ie, a single differential and cross axle behind the gearbox. on each end of the crossaxle was a '' T'' shaped bevel gearbox with driveshafts running for and aft to a 90 degree bevel gearbox that drove each wheel. The Alvis's had a NoSpin (Detroit locker) in the single differential, but I believe the Ferrets had an open diff, and a suspension system with very little articulation, so weren't very capable, but with modern hydraulic or pneumatic struts interconnected front to rear and a selectable difflock could be greatly improved.

I am getting the feeling of de ja vu. Have we covered this subject previously?

Bill.

Yes, that's be basic idea - I've also got a feeling of de ja vu. I've played with both Ferrets and Sarracens (lots of fun although the B60 and B80 engines seemed to suffer from fuel and igntion problems we never got to the bottom of) which is where some of my ideas are coming from. Although ferrets have limited off road capability they get a lot further than you'd expect. I found they'd happily show standardish series land rovers and 101's the way a lot of terrain.

[Les Henson]

Vapour text:-

My version: Initial designs complete, scale drawings finished July '07, build starts August '07. ~100" wheelbase, 18" of travel at each corner & fully adjustable, 4 wheel steer, skid steer, CTIS, Porche flat 6 power. Target weight 1500 kgs ready to roll with drivers and kit

Les.

[Corrode Finger]

So is there no other examples of indi susp mud pluggas(rather than racers) out and about?

I do think that the frog ha s a all terrain forklift look too it, if it is based on that it may explain the reasons behind the 'reluctance' to drive between stages, i certainly would not wnat to go far in a telehandler on th road, rather slow if nothing else.

Is my memory failing or am i getting crossed wires but are some of the american/ australian rock crawlers running mad indi suspension? Just seems interesting to ask?

[Hybrid_From_Hell]

erm

Have you considered just 'sorting out' the current one ?

Nige

[bill van snorkle]

Although ferrets have limited off road capability they get a lot further than you'd expect. I found they'd happily show standardish series land rovers and 101's the way a lot of terrain.

With apologies to dyed in the wool series and 101 enthusiasts that is not saying much. My neighbors conventional 2wd Ford Falcon Station wagon would also show them a clean pair of heels in terrain that require a bit of articulation.

Corrode Finger, I believe indy suspension was tried on a few uS rockcrawlers but found wanting for those conditions. Apparently if the competition regs are ever changed to permit forced articulation it may make a comeback, but there is a camp that believes that the high percentage of unsprung weight that solid axles provide is a big stability advantage in that terrain.After my limited experience observing Pinzgauers, Haflingers, and trying to make the family Trooper do anything offroad without the risk of turning turtle, I'd have to agree.

Bill.

[FridgeFreezer]

The Baja buggies have insane travel and are indy, but they're for keeping wheels on the ground at full tilt over rocky terrain / big jumps and don't really do anything slowly from what I've seen.

[simonr]

That's a good point, Bill. One I had not considered, that a heavy unsprung axle is under some circumstances going to give you a lower C of G than indi. From what I've read though there are a few competitive rock crawlers with indi - but they are viewed as having some dedication because of how difficult it is to build something decent compared to bolting a couple of truck axles to a frame.

The sample however is not big enough to really see how they stack up against beam axles.

In the UK and Europe there is less Rock Crawling, and what there is looks a bit gay compared to some of the things the Yanks get up to. A good proportion of what we seem to do involves booting it up a slippy slope, through mud or other traction challenging things.

I feel that in these circumstances, Indi has an advantage in being able to keep the wheels in contact with the ground more of the time - leading to more traction. It might well come a cropper on tricky, technical side-slopey bits.

Everyones truck is a balance of compromises - but most have the same compromises. I wonder if by changing something fundamental and changing the things it is good at compared to most trucks, it might give you an advantage on challenge type events. If you are the only truck to get one punch, that could be worth 10 that everyone else can get?

Si

[will_warne]

erm

Have you considered just 'sorting out' the current one ?

Nige

Yes and no corners will be cut either

[will_warne]

With apologies to dyed in the wool series and 101 enthusiasts that is not saying much. My neighbors conventional 2wd Ford Falcon Station wagon would also show them a clean pair of heels in terrain that require a bit of articulation.

Corrode Finger, I believe indy suspension was tried on a few uS rockcrawlers but found wanting for those conditions. Apparently if the competition regs are ever changed to permit forced articulation it may make a comeback, but there is a camp that believes that the high percentage of unsprung weight that solid axles provide is a big stability advantage in that terrain.After my limited experience observing Pinzgauers, Haflingers, and trying to make the family Trooper do anything offroad without the risk of turning turtle, I'd have to agree.

Bill.

As you say, I think the big problem with most indi vehicles is lack of articulation. I can see what your saying about lack of unsprung weight and that could be an issue - its a reason for building what I intend to as there will still be a reasonable amount of unsprung weight.

[bill van snorkle]

That's a good point, Bill. One I had not considered, that a heavy unsprung axle is under some circumstances going to give you a lower C of G than indi. From what I've read though there are a few competitive rock crawlers with indi - but they are viewed as having some dedication because of how difficult it is to build something decent compared to bolting a couple of truck axles to a frame.

The sample however is not big enough to really see how they stack up against beam axles.

In the UK and Europe there is less Rock Crawling, and what there is looks a bit gay compared to some of the things the Yanks get up to. A good proportion of what we seem to do involves booting it up a slippy slope, through mud or other traction challenging things.

I feel that in these circumstances, Indi has an advantage in being able to keep the wheels in contact with the ground more of the time - leading to more traction. It might well come a cropper on tricky, technical side-slopey bits.

Everyones truck is a balance of compromises - but most have the same compromises. I wonder if by changing something fundamental and changing the things it is good at compared to most trucks, it might give you an advantage on challenge type events. If you are the only truck to get one punch, that could be worth 10 that everyone else can get?

Si

I vaguely recall reading oh so many years ago (maybe 20 or so) in a very early(black and white I think) British offroad magazine, a fairly detailed article about a company that converted RangeRover axle assemblies to independant for safari type racing. They chopped the banjo housings short, made short flanged halfshafts, Open CV jointed driveshafts to the standard RR swivel and hub assemblies. there was a bracket bolted to the swivel ball flanges and rear stub axle flanges to which the indy control arms attached. I can't remember any other details but do any of the forum members have any knowledge of this conversion and how successful it was in a variety of conditions?

Bill.

[FridgeFreezer]

No idea but I know LR built an Indy Series (no, really) to test it out and found it was no better than standard (and presumably had more bits to make / go wrong) was it because the Austin Gypsy was indy or something like that? It was definitely in response to a rival vehicle anyway. There was an article in one of the comics ages ago about it, had some piccies of the setup and details of the performance.

Obviously technology has moved on since then but I do wonder how much one can reinvent the wheel here - beam axles do work well for off-road just as indy works well on-road / at speed. You can refine both systems so that their performance converges towards each other it's just which end you arrive from I guess

[najw]

If we did more "special" stages against the clock then indi would undoubtedly have more of a following- Rog (istruggletogate11) had a really nice rock buggy which had indi suspension- unfortunately never got to see it running for real but the piccies and vids suggest it was very effective.

That was my Rock Rod

[will_warne]

I vaguely recall reading oh so many years ago (maybe 20 or so) in a very early(black and white I think) British offroad magazine, a fairly detailed article about a company that converted RangeRover axle assemblies to independant for safari type racing. They chopped the banjo housings short, made short flanged halfshafts, Open CV jointed driveshafts to the standard RR swivel and hub assemblies. there was a bracket bolted to the swivel ball flanges and rear stub axle flanges to which the indy control arms attached. I can't remember any other details but do any of the forum members have any knowledge of this conversion and how successful it was in a variety of conditions?

Bill.

I never heard about that, Bill. It sounds quite interesting!

FF, I remember vaguely reading that too. I can't remember whether it was something like a Gypsy / Series LR hybrid that was used for testing after BL aquired Austin.

[Steve Hiatt]

I vaguely recall reading oh so many years ago (maybe 20 or so) in a very early(black and white I think) British offroad magazine, a fairly detailed article about a company that converted RangeRover axle assemblies to independant for safari type racing. They chopped the banjo housings short, made short flanged halfshafts, Open CV jointed driveshafts to the standard RR swivel and hub assemblies. there was a bracket bolted to the swivel ball flanges and rear stub axle flanges to which the indy control arms attached. I can't remember any other details but do any of the forum members have any knowledge of this conversion and how successful it was in a variety of conditions?

Bill.

Peter Phillpotts of Off Road design did this some years ago. I have an independent racer with Landy hubs, stubs and 110 outer CVs. The uprights are fabricated. It uses BMW diffs, the last LSD super strong diff was £40

It manages 13.5 inches of wheel travel. I have about 12" clear under the car everywhere on 235/85/16 tyres.

Couple of otherpoints, you get a smooth underline with an indy and the wheels are nearly always in contact. Last safari I was able to take a rough short cut that the axled boys couldn't get over