8 wheeled APC questions

[Enigma229]

Happy new year everybody!

I'm now moving onto an animation of some Soviet BTR-70's:



Going through the threads I came across this post by Luigi:

http://forum.craftanimations.com/viewto ... eeler#p305

which is in response to Solomon's post:

http://forum.craftanimations.com/viewto ... eeler#p298

The vehicle Solomon was inquiring about seems like it would have a similar rig like the BTR-70. So my question is would I set it up like the image in Luigi's post?

My second question is what would be the linking of the Extra Wheel objects?

The manual is a bit nebulous in this matter to me. Linking the Extra Wheel's GravityDirectionMesh to the ground I understand.

Would I link the Extra Wheel's ChassisSuspensionMesh to the 4 wheeler's ChassisRelocatorMesh?
Would I link the high poly wheel to the Extra Wheel's WheelMesh?
If so do I link the WheelMesh to the high poly body?

Sorry to hear about the spam.

[Carl Buhre]

Happy new year everybody!

Thank you and a happy new year to you too!

So my question is would I set it up like the image in Luigi's post?

Yes.

Would I link the Extra Wheel's ChassisSuspensionMesh to the 4 wheeler's ChassisRelocatorMesh?

Yes.

Would I link the high poly wheel to the Extra Wheel's WheelMesh?

Yes.

If so do I link the WheelMesh to the high poly body?

Nope. You're already done with all the linking of the ExtraWheel at this point.

[Enigma229]

Thanks Carl. I think that should work.

Just using the rig, I am getting some collision issues.

Here is the 3ds Max 2009 file to give you a better idea: btr_rig.max

[Luigi Tramontana]

Hey Enigma.

• - First thing i notice is that the terrain is to coarse. You can still simulate it with a low-poly mesh, but when finished you should smooth the mesh and resimulate from where you begin drivin on the hilly terrain.
  - Secondly you could make the ride even more realistic by slightly increasing the ray multiplier.
  - Thirdly I notice that you brake the vehicle by using the skid brake, which you can if you wish, but I would suggest you use the ABS brake instead since you cannot lock the extra wheels (I have put this to the hotfix todo list ). You should also install the latest BETA version of the 4-wheeler and check the "Use Reverse As ABS Brake".
  - Fourthly there is an inherent lack in this simulation setup which is the fact that the extraWheels does not contribute to the physics per se and therefore hills are quite problematic and should be diminished if possible.
  - Fifthly: If you intend to drive forward that particular configuration is not necessary at all since it is only important when the 8-wheeler turns, because it uses both front wheels for the steering. If that is the case your remedy is to put the two extra wheels in the middle. Ideally use a Craft Crawler with 8 extraWheels.

Hope this helps you on your quest for Craft knowledge!

[Enigma229]

- First thing i notice is that the terrain is to coarse. You can still simulate it with a low-poly mesh, but when finished you should smooth the mesh and resimulate from where you begin drivin on the hilly terrain.
- Secondly you could make the ride even more realistic by slightly increasing the ray multiplier.
- Thirdly I notice that you brake the vehicle by using the skid brake, which you can if you wish, but I would suggest you use the ABS brake instead since you cannot lock the extra wheels (I have put this to the hotfix todo list ). You should also install the latest BETA version of the 4-wheeler and check the "Use Reverse As ABS Brake".
- Fourthly there is an inherent lack in this simulation setup which is the fact that the extraWheels does not contribute to the physics per se and therefore hills are quite problematic and should be diminished if possible.
- Fifthly: If you intend to drive forward that particular configuration is not necessary at all since it is only important when the 8-wheeler turns, because it uses both front wheels for the steering. If that is the case your remedy is to put the two extra wheels in the middle. Ideally use a Craft Crawler with 8 extraWheels.

- First thing i notice is that the terrain is to coarse. You can still simulate it with a low-poly mesh, but when finished you should smooth the mesh and resimulate from where you begin drivin on the hilly terrain.

Good to know.

- Secondly you could make the ride even more realistic by slightly increasing the ray multiplier.

Will this reduce the tires from going through the vehicle body?

- Thirdly I notice that you brake the vehicle by using the skid brake, which you can if you wish, but I would suggest you use the ABS brake instead

My bad. I just got this gamepad and haven't mastered the many buttons on it.

- Fourthly there is an inherent lack in this simulation setup which is the fact that the extraWheels does not contribute to the physics per se and therefore hills are quite problematic and should be diminished if possible.

So what would I do to remedy this?

I tried matching the relevant ExtraWheel settings from the 4WheelerExt settings. I played around with the different 4WheelerExt presets but I am not sure what preset would fit an APC vechicle like the BTR.

[Luigi Tramontana]

Ok, just realized a quite simple solution that shold work great as long as you keep the vehicle in motion.

1. Rig the 8-wheeler as an ordinary car.
2. Rig the 4 center wheels with extra wheels.
3. In the front ExtraWheels' config dialogs simply uncheck "fixate wheel". This should remedy the issue (as long as you keep the vehicle in motion)

[Enigma229]

Thanks Luigi. I will give that a try.

[Enigma229]

Hey guys,

I'm tackling this BTR again. I'm back where I left off in January and still having the issue of the wheels (particularly the Extra Wheels) colliding into the BTR's body.

Any new suggestions since I last posted about this?

[Carl Buhre]

Hey guys,

I'm tackling this BTR again. I'm back where I left off in January and still having the issue of the wheels (particularly the Extra Wheels) colliding into the BTR's body.

Any new suggestions since I last posted about this?

Did you try Luigi's suggestion?

Ok, just realized a quite simple solution that shold work great as long as you keep the vehicle in motion.

1. Rig the 8-wheeler as an ordinary car.
2. Rig the 4 center wheels with extra wheels.
3. In the front ExtraWheels' config dialogs simply uncheck "fixate wheel". This should remedy the issue (as long as you keep the vehicle in motion)

[Enigma229]

Yeah I gave that a try again but the middle wheels still go through.

Here is the file for you to take a look: BTR_02

It's 15 MB because I have a dense terrain and I upped the Ray Cast parameters.

EDIT: It's between frames 350 - 450 where you can see the problem.

[Carl Buhre]

Hmm, then maybe this could work:


I scaled up the 4-Wheeler's wheels so that they cover two of the wheel pairs (remember to unlink/unparent the high poly wheels before scaling):


And then I added ExtraWheels to replace outer wheel pairs and then linked/parented the high poly wheels to the new ExtraWheels instead (the big wheels are hidden in this image):

[Enigma229]

I tried that but no luck.

I tried different settings for the suspension (in the 4 wheelerExt parameters) and I think that does help. It seems I would have to tweak the front/back stiffness values at different parts of the animation. Perhaps that in combination with changing the chassis relocator during the animation as well.

[Enigma229]

Oh wait a second... I might be able to manually keyframe the chassis relocator on the frames where the wheels go through the body by using the idea you just posted above.

This may be tricky though because if I run the simulation after any manual keyframing, those keyframes will be erased.

[Luigi Tramontana]

Rather than keyframing the chassisRelocator you should simply keyframe your high-poly model.
1. move the timeslider to a position just prior to the penetration.
2. Create a keyframe there for your high-poly surface (or even better a dummy and then your high-poly to avoid non-uniform scale problems).
3. Copy this key.
4. now keyframe the high-poly so it does not penetrate.
5. Exactly when you have passed the time period where the penetration occures, paste the key you copied i 3, and the high-poly should come back to "normal"

[Enigma229]

Gentlemen!

It's been a while since I've been on here but I am back and the new site looks great.

I'm now set up with CDS on Max 2010 and ready to tackle some old projects from earlier in 2009.

Are there any enhancements to the tools that would help me out compared to a year ago? I still want to work on that Soviet BTR-70 APC and here is the thread to remind you of what I'm talking about: http://forum.craftanimations.com/viewtopic.php?p=1499.

I haven't touched it since Luigi's last post on there so again, if there are any new tools and enhancements that would make this easier, I'm all ears!

[Carl Buhre]

Gentlemen!

It's been a while since I've been on here but I am back and the new site looks great.

I'm now set up with CDS on Max 2010 and ready to tackle some old projects from earlier in 2009.

Are there any enhancements to the tools that would help me out compared to a year ago? I still want to work on that Soviet BTR-70 APC and here is the thread to remind you of what I'm talking about: http://forum.craftanimations.com/viewtopic.php?p=1499.

I haven't touched it since Luigi's last post on there so again, if there are any new tools and enhancements that would make this easier, I'm all ears!

Hello Enigma229,

It's nice to see you back. The next version of Craft 4-Wheeler Extended will introduce something called "Wheel Ground Release" that enables the 4-Wheeler's wheels to lift from the ground. This might be something that could help you with your animation. You can try out the BETA version of it here: http://forum.craftanimations.com/viewto ... f=12&t=642

[Carl Buhre]

I think I have found a setup that works pretty well with the regular (9.3.1) version of Craft Director Studio:
http://www.craftanimations.com/tasks/si ... gged03.max

[Enigma229]

Carl, I finally got back to this and opened the file. Will this only work if the wheels are not turning like in the max file?

[Carl Buhre]

Carl, I finally got back to this and opened the file. Will this only work if the wheels are not turning like in the max file?

If you want the wheels to turn I would recommend using Craft CogWheels (with reverse direction check in its config). You can combine it with a 1DRotator which is using the same input that you're using to turn Right/Left.

[Enigma229]

Thanks Carl.