Bogging data

[Wreck]

One issue here is bogging rate as versus immobilization rate.

I did some tests with Shermans (mids), using Lt Bull's earlier posted setup. Put 10 dirt roads perpendicular across the middle of the run, the rest of it (2km) being just grassXT. Then I ran my 20 Shermans across it back and forth (reverse), two times. So total distance of about 8km, half in reverse.

There were 5 bogging incidents in the grass, but only one turned into immobilization.

There were 4 bogging incidents on the borders of a road (which is impressive when you consider that there were 240 action spots worth of grass and just 10 of roads). Of these 3 turned into immobilization. So the "conversion rate" appears to be very high -- 75%. (By comparison the conversion rate for the grass that I saw was 20%; the rate that Lt Bull saw in mud with many data points was 10%.)

I do not have a strong opinion on whether in terms of simulation accuracy bogging when part on/part off should be common. (I tend to think not, but some decent arguments have been advanced here...) I do think that it is a bad thing as a game-mechanic, since as others have pointed out it is very difficult to keep tanks exactly on the roads, and yet they have a driver who should be doing that if it is so important. Also, I would add that the way in which CM is forced to model roads -- fitting them into a square grid -- makes it much harder to be that tank driver on any roads except those straight roads exactly aligned to the grid.

But even if we allow that bogging on roadsides might have been common, immobilization is different. I find it hard to accept that a vehicle, tracked or not, that is half on the road would not be able to get unbogged. The rate of conversion that I saw is about 10 times too high.

[c3k]

Guys, the data - backed by testing - is great. Thank you.

[SlowMotion]

One issue here is bogging rate as versus immobilization rate.

...

But even if we allow that bogging on roadsides might have been common, immobilization is different. I find it hard to accept that a vehicle, tracked or not, that is half on the road would not be able to get unbogged. The rate of conversion that I saw is about 10 times too high.

Agree. I could understand that moving away from road would be slow, like Rhinos driving through bocage and it would sometimes cause bogging, but IMO this immobilization is too common. But opinions from tankers would be useful here of course.

[YankeeDog]

I do not have a strong opinion on whether in terms of simulation accuracy bogging when part on/part off should be common. (I tend to think not, but some decent arguments have been advanced here...) I do think that it is a bad thing as a game-mechanic, since as others have pointed out it is very difficult to keep tanks exactly on the roads, and yet they have a driver who should be doing that if it is so important. Also, I would add that the way in which CM is forced to model roads -- fitting them into a square grid -- makes it much harder to be that tank driver on any roads except those straight roads exactly aligned to the grid.

I think this is the most important point. As I noted above, driving a vehicle 1/2 on, 1/2 off a road probably would be a good way of getting stuck, especially if we the road is edged by some sort of drainage ditch or gravel verge. The larger the difference in traction between the road surface and the verge, the more difficult the vehicle will be to control. Just how likely it would be for a vehicle being driven like this to get stuck is hard to quantify as it depends a lot on exactly what the edge of the road is like, exact details of the vehicle etc. I tend to doubt it would usually be as bad as these tests seem to indicate, but it's not the kind of thing for which there's going to be readily available real life data so we can probably speculate on this topic for weeks without coming up with any definitive answer.

But as far as the gameplay goes, I really don't want to have to drop down to level 2 view every time I'm plotting vehicle waypoints near or on a road in order to make sure I don't accidentally put a waypoint 2 meters too far one way or the the other and accidentally instruct the vehicle to drive with one track in the ditch.

IMHO, either the vehicle driver AI needs to be modified so that drivers "know" not to drive with one track on a road verge for any distance, or this bogging/immobilization behavior needs to be dramatically toned down so there's not such a high chance of the player being penalized if he plots a waypoint a meter or two off. The former seems to me to be something that would be tricky to code and implement. The latter seems to me to be an acceptable, simple abstraction. Applying the KISS rule, seems to me this is the way to go, then.

[noob]

What terrain mod are you using ?

[LemoN]

Hmm, I always thought there was something wrong with immobilisations on roads being extremely common.

Now that I think of it most immobilisations have indeed been at the edges of roads.

[Chek]

I have four platoons of identical panthers (each platoon is 5 pathers). The map is completely flat wet grass, with some roads overlaid.

An interesting test,but in reality I personally am not going to push armour onto completely flat wet grass unless I feel I absolutely have to and when I do I would be expecting a large proportion to become immobilised at least for game purposes.

Most of the tanks bogged in these conditions would not be retrievable within the games time frame and would most certainly not be done under fire.Their fellow tankers would not be stopping to extricate their brothers in arms because they too would likely become bogged in the process,and they would be unwilling to expose themselves to fire(in more ways than one)and of course there will be an officer somewhere hassling them to do their job.Not to mention it's going to take a while.

This is just where I'm at when I play this game.

[Erwin]

Within a single battle it's not a huge problem even tho' it is irritating. But, it can ruin a campaign if one loses 20%+ of one armor to bogging/immobilizations each battle.

In HOFFNUNG I started with 5 Panthers and 5 MkIV's and by battle 5 or 6 I was down to 2 of each with all but one loss being due to immobilizations. And I was moving very carefully on SLOW all in every battle.

As I said b4, this isn't supposed to be CM: TANK DRIVER SCHOOL.

[TheBlackHand]

I just finished a battle (possibly my last) in the campaign "Die Letzte Hoffnung". This would otherwise be an outstanding campaign that should be taylor made for a game like this . . . except the game has ruined it. I have lost TEN tanks in this campaign to bogging. I have lost ONE to enemy fire. The majority of these tanks have become immobilized while making simple moves along the roads. I lost four in this last battle during dry conditions. This is flat-out wrong and it has got to be fixed.

I've heard a lot of people call the game "unplayable" for this or that reason, most of them bogus . . . however, I have to say, this problem is beginning to make the game un-enjoyable and very close to unplayable, for me. It has certainly ruined this particular campaign, for me.

Playing with tanks is fun and this great campaign gives them to you in spades. Micromanaging these tanks around every turn and fretting over when one (or all) of them will catch an edge is NOT fun.

It's stupid.

This is number one on my hopes for fixin' in the next patch/module.

[wombat_of_war]

it definitely wasnt that bad in real life for the tanks on the western front..ive read of full battalion armoured assaults on towns in well muddy doesnt begin to cover it "bogged up to the turret" and even in conditions like that 3 were lost to enemy fire while 2 were bogged and had to be destroyed.. it seriously needs looking at for the next patch

[Redwolf]

I think this is the most important point. As I noted above, driving a vehicle 1/2 on, 1/2 off a road probably would be a good way of getting stuck, especially if we the road is edged by some sort of drainage ditch or gravel verge. The larger the difference in traction between the road surface and the verge, the more difficult the vehicle will be to control.

I can do that with my BMW that is so flat on the ground I can park it under some F-150s, has rear wheel drive only and the polar opposite of all-terrain tires. Without ever getting stuck.

If the assumption is that there is a ditch then it need to be explicitly modeled and the terrain needs to show it. And(!) the TacAI when it is reinventing your path should go to it.

Overall I still think it is far more likely that we look at broken code here.

[Guest]

ian.leslie: thanks for the heads up.

TheVulture - thanks for your work. I'll be taking a look at this. Please check your PMs.

[YankeeDog]

I can do that with my BMW that is so flat on the ground I can park it under some F-150s, has rear wheel drive only and the polar opposite of all-terrain tires. Without ever getting stuck.

If the assumption is that there is a ditch then it need to be explicitly modeled and the terrain needs to show it. And(!) the TacAI when it is reinventing your path should go to it.

Overall I still think it is far more likely that we look at broken code here.

Actually, as long as it has enough ground clearance to keep from high-centering, it's the BMW that has the advantage over many other vehicles in this situation. Most modern sports cars have an electronically regulated differential system that prevents all of the power from going to one side of the vehicle if that side starts to spin out. Rear wheel drive is also an advantage in this situation, because it means both of you your front, steering wheels "float" over the terrain, rather than attempting to pull the vehicle, and this makes it easier to maintain steerage.

It's a front wheel drive vehicle with a simple mechanical differential that's worst off in this type of situation.

But regardless of details of the vehicle, my point is simply that a vehicle has one side on a graded road, and one side on, say, moderately loose soil, may actually be worse off than a vehicle that has both sides on moderately loose soil.

But this is all really an unnecessary tangent. As to the essence of the issue here, I agree with you: Except for special circumstances such as a deep, muddy ditch running along the side of the road, I don't think that the penalty for driving 1/2 on, 1/2 off the road would generally be as extreme as the game seems to model it. Further, I'm not convinced the game should actually model such a penalty *at all*, given the nature of the game, and the fact that avoiding such penalties requires what I consider unnecessary micromanagement of waypoints by the player (or, alternatively, substantial new AI pathfinding code, which I think is effort better spent elsewhere).

[Chek]

Within a single battle it's not a huge problem even tho' it is irritating. But, it can ruin a campaign if one loses 20%+ of one armor to bogging/immobilizations each battle.

That is a good point especially on the side that's advancing.

[Redwolf]

The problem isn't that they model a ditch and assume that getting one side of the vehicle into the ditch will impact mobility. That's fine.

Problems are:

1) every road seems to have it which isn't realistic at all, and even roads in Europe that have drainage ditches have frequent patches where you can cross them

2) it isn't marked as such in terrain data

3) the tacai doesn't know about it and when it does it's usual path-reinventing on traffic jams it will drive into these ditches where a real driver (or commander) would not

Unless these issues can be fixed this piece of code should rather be turned off altogether instead of turning it on if that means this broad a brush.

[Praetori]

That is a good point especially on the side that's advancing.

We can tow guns but not vehicles.

We can reload squads but not vehicles.

It's been bugging me since, well always.

If the assumption is that there is a ditch then it need to be explicitly modeled and the terrain needs to show it. And(!) the TacAI when it is reinventing your path should go to it.

I've always thought it was modeled. At least there's some sort of ditch like depression along every road in the game by default.

The vast majority of combat vehicles I've seen stuck have been in ditches along the road. I've come across a few bogged tanks in open terrain (once a Leopard 2 halfway up a huge Oaktree but that's a different story) and even a MTLB stuck in the middle of a pretty dry field (though it was for some reason VERY damp where the thing got stuck).

Drivers tend to be careful in the terrain and pretty careless while on the road. I have no hard facts regarding this but at least a theory.

Most boggings I've seen have been due to obstacles the driver didn't see. Ditches are generally close to the vehicle and it's often along the direction of travel which makes them very hard to properly observe from within. The depth and composition of the ground conditions in the ditch are very hard for the driver to assess. Commanders are generally not guiding the driver as he would while in the terrain while the vehicle is on the road and the speeds are usually much higher.

When it comes to MBTs and AFVs they're pretty damn heavy compared to most other things on the road while being broader as well (and they're not following the centerline as good as a truck for example). A road surface that's wet will often crumble beneath a heavy tank (I've seen one sliding into a ditch while the road just dissolved under it, though it didn't get stuck that time). Even tarmac isn't immune to breaking.

Driving anywhere then dead center on a gravel or dirt road is asking for trouble (which I'm sure tankers in this forum can vouch for).

Some nice but typical pixx I found:

Edit: And in reality there's all kinds of trouble when moving a large armored column. Stuff breaks down, vehicles get stuck and so on. But most of it is handled quickly and efficiently, often within the Battalion or even Coys by other tanks or dedicated towing vehicles. We're talking minutes to get a AFV or MBT unbogged if you have the resources handy.

[A Canadian Cat]

<snip>I've come across a few bogged tanks in open terrain (once a Leopard 2 halfway up a huge Oaktree but that's a different story)<snip>

I would love to hear that story:D Were they trying to push the tree over?

[Praetori]

I would love to hear that story:D Were they trying to push the tree over?

Well I actually met the crew as they trodded along on foot (helmets still on) on their way to a briefing.

When I asked what unit they were from and where the tank was thy started acting strange.

Turned out they wanted to try and knock the oak over (though the crew didn't outright admit it and had some twisted sort of logic explanation) but it didn't break (or even bend much) and the Leo ended up on straddling the tree a bit up (it had actually been hanging without ground contact for some time before settling on the rear).

They had some idea about swinging the turret around to get down but they couldn't cover up the fact they got stuck without getting late to the briefing so they simply left it there in the meantime.

I of course reported it in and then laughed my ass off as I was driving off.

Sadly it was before the time of the digital camera.

[Guest]

Just to restate in case anyone missed it last page: this problem is being looked into. Thanks to those who have provided data and tests.

[Erwin]

Thank you, Phil.

[Mord]

You might wanna post that ten more times, Phil...If history on this forum has taught us anything it would be why let "we're looking into it" get in the way of a good bitch session?

Mord.

[TheBlackHand]

Indeed, I was all prepared to lay out another gripe because I opened up my campaign this evening to find that it has been completely derailed by this bogging glitch.

It is refreshing and a real confidence builder to hear an official "we're looking into it".

Now, I'm gonna try to forget everything about this campaign, except that it'll be worth playing when the roads are suitable for tanking.

In fact, I'm going to lay off the heavy armor scenarios/campaigns altogether until "looking into it" becomes "fixed it".

[Ranger33]

Good to hear it's being looked into. Since reading this thread I've avoided roads entirely (even on wet terrain) and noticed a sharp dropoff in bogging.

[LemoN]

Pics of M1 sinking in an ocean of mud next to a road

I can't see how this would be a "normal road situation". In game this would have to be represented by a patch of swamp on the side of the road.

[Praetori]

I can't see how this would be a "normal road situation". In game this would have to be represented by a patch of swamp on the side of the road.

Hardly normal as it's a pretty extreme derailing. But it puts some light on a not too uncommon phenomenon when driving armored columns up a road. The first few tanks can pass fine then suddenly the embankment slides down into a ditch taking a vehicle with it. Usually the tank or afv can just drive away but sometimes they get stuck. Roads are sometimes best avoided by armor if there's suitable terrain elsewhere (though that's in part due to the channelizing nature of roads).

A motorized march across several kilometers of dirt or gravel road usually leaves the roads in a complete mess (often the folly of the trailing support which is often wheeled). This of course changes from country to country as some build roads sturdier than others, and on the terrain in general.

There's a reason the Autobahns built in Germandy during the 30's were concrete monsters.