Training Stream - Tank Vehicle - March 17th, 2015

In 3dsmax 2014, with UE 4.6.1, I can export with sockets on my static meshes and their position works great. But in the cases where I need specific socket orientation, I cannot figure out how to get the correct output results in UE4, probably due to the rotation order difference in max vs UE4.

looks like you have got the wheels turning with the tank working pretty well:), its a shame UE4’s vehicle system is still buggy.

Q: would your wheel turning system work with the normal vehicle setup?

It is based on the vehicle system but it is different simulation type.

Lesson for use, or source Projects to study possible?

Hi,
Yeah ! Thank you for the Youtube video .
Thank

I was just watching this and it looks like the track sections between the roadwheels are modeled as part of the wheel. If you can model the tracks as seperate meshes and then skin them to the wheel joints, blending the weights from one joint to the next the tracks will follow along with the wheels very nicely. I havent tried this in UE4 but this method works elsewhere and should work fine here too.

I started this tutorial hoping to get a working tank like vehicle running, but you completely skip over how physics and collision get applied to the vehicle, it goes from getting setting up the inputs and offsets/rotation straight into working on the guns and treads. And there’s no project files to look at. So how do I go from getting a tank moving along a plane with no gravity or collision to one interacting and with gravity?

Are the files available for this tutorial yet? I’m fairly new to blueprints and get lost around the 20 minute mark. This is the point where starts setting up . He opens and closes many tabs and it’s hard to follow. Also, I’m not sure what components in the blueprints he is using as it’s being glossed over.

Hey Everybody, Thanks for checking back in to the thread.

The assets have not yet been released. Shortly after this stream, I began working on an improved version of the tank based on feedback I received. It is skeletally based, an driven via physics. It is going to take a little while longer to put together, but eventually we will release it through the Learn Tab. Please hang tight!

Here’s a sneak peek of the current work in progress:

TANK WIP

It’s pretty slidey right now, and I need to improve the suspension, but it is getting there.

That look much better, that is well optimized like the BF tanks ?
*Looks like the treads of the top have issues and move like the bottom.

News about that new tank Alan ?

So this s where the tank is:

The final piece that needed implementation was the weapons system. With a little bit of modification, that came across without too much trouble from my original tank.

However, a new issue came to light: the method by which I was rotating the turret and barrel was a problem: their collision was not being updated to match the mesh.

The core of the problem is the mixing and matching of simulated and kinematic bodies. The base of the tank is simulated. The turret was to be kinematic, as that seemed like the most straight forward solution: get some input and use that to rotate the mesh or bone it is attached to. However, physics and animation don’t necessarily mix well; one system doesn’t necessarily know or operate with the other.

To bring it all under one house, a solution was tried where the turret and barrel were instead simulated and driven by physics: Input came in, math was done on it, and that was converted to torque which was applied to the turret and barrel’s parent bones.

Unfortunately, the barrel was subject to gimble lock. Without the ability to change axis order when evaluating rotations in UE4, I couldn’t quickly fix it. Also, while the turret seemed to work under this system, I do not have confidence in it. I suspect I just got lucky with the combination of constraints and axes I was using. That’s not a reliable solution to be endorsing for release.

Several alternate implementations have been tried to circumvent the issue, but at this point, I require assistance from our physics people, who are currently working on high priority tasks on our game projects.

The question now is: release it as is, knowing the turret collision isn’t working and let the community work around it, or wait until it can be fixed?

Then will be better wait until it is fixed or release now and after fix update with a patch.

I think you could release it unofficially, and see if the community can help you find a way around or develop an alternative method.

This is precisely what I was hoping for as well. But for whatever reason, whenever a newcomer has a question like this “how can I get the tank/pawn to move while it’s simulating physics” suddenly all are silent. like it’s some deep dark secret that everyone who knows is too ashamed to tell it.

It looks like is making progress on the tank https://vine.co/u/1125240305424502784

That is from 2 months ago.

That really doesn’t help those of us who just want to know the basic method of getting the dang thing to move while colliding with objects. Hopefully one that doesn’t involve making the tank slide around like ice on a warped skillet.

Hey all. Thanks for keeping the thread alive. Progress has been made. The turret and and cannon barrel are now updating their collision. Everything is working as expected. I have begun the documentation process of the graph.

I am on the road for the rest of the month, but when I get back, I’ll pick this project back up and start on the supporting materials, provided no other high priority tasks come up!

This is really good. Thank for the heads up Alan :smiley: