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Vehicle Max Suspension Rise Issue/Bug.... along with other issues

Hey everyone, running into an issue with my vehicle project. So, I have the Suspension Max Raise (how high the wheel can go when the car falls to the ground) set really high (1000) so that my car/boat sort of bobs beneath the ground when it falls. This is what I want. Problem is, whenever I try and drive beneath a low hanging edge, my car spazzes out (by that I mean either it gets shunted under the ground, or gets sent off into the sunset). I tried lowering the Suspension Max Raise and that seems to fix it, but I really need it to stay at a high number. Ideally, I just want it to not look above the car for suitable places to put the tires (which is what I think is happening). This is my current and biggest problem. Anyone able to help me?

As for the other issues, I need help figuring out:

  1. why/what is causing my car/boat to magically flip right side up right before it hits the ground (and sometimes even when it is near other geometry while still in mid air).
  2. how to prevent the car/boat from going through the ground when doing a nosedive fall (nose is pointed straight down).

Here is a video of the issues as best show them.

It would be great if someone at epic could throw me a bone and give me a hint of where to look, or at least tell me if this is a bug or working as intended?

Hey Knobbynobbes. It looks like a cool approach to make a boat vehicle.
From my experience with UE4 implementation of vehicle movement component, the suspension works by checking for collision from max suspension raise till suspension lower limit and adds the wheel radius to the collision point and moves the wheel object there. The wheel object itself is not physx based and doesn’t have any collision box. I made a video which shows the problem of how wheels behave currently - https://youtube.com/watch?v=Gj7sW38vYYY

About your issues:

  1. On your video - the mid air collision happens when the vehicle up axis is pointing towards the collision object and the suspension max raise raycast detects a collision with that object, notice that it doesn’t happen if you have low values of max raise.
    Same thing for driving under objects, because it’s a raycast from above the vehicle, it moves the wheel object above the bridge if collision is detected.
  2. I don’t know what you mean by that exactly but maybe try making a spehere with a constraint, one end attached to the mesh and the other attached to collision object which only has collision enabled for statics (kind of like you would attach a bouy to a boat using a string).

About the whole boat project - I would suggest you try to ditch the vehicle movement component and try to apply forces to the physics object model with constraints of your own design, this way you would have much more control over how it behaves.

Hhhhhmmmmm, I have thought about doing my own vehicle type, even tried it by following the hover car tutorial here:

And I’ve seen the stuff from Space Dust Racing and their video giving a general idea of how they made their vehicles, but upon testing it, I always come back to the three (kinda 4 really) same issues that I don’t know how to implement that are absolutely necessary for this to work.

  1. I don’t know how to create the ‘suspension’ that allows the boat to move around freely from the wheels. Yea, the wheels will move where the boat moves, but it seems more like the boat gives the ‘area’ where the wheels will do their thing, and the wheels themselves give the exact location of where the boat wants to be. But being able to say that and putting it into blueprints are, for me at least, worlds apart.

  2. When I tried making my boat as a hover car, I had the issue that it was very bouncy. Even when dampened, the whole thing remained a pain to stabilize. Epic’s vehicle component, on the other hand, always seems very ‘stuck’ to the ground (in a good way) and that is something I don’t know how to replicate. I may be wrong, but I don’t think it was using something like addforce or addimpulse to make the vehicle go where the wheels tell it to. At best, I think it might have something to do with the virtual wheels (the Shape and Wheel sections of the VehicleWheel blueprint class) that were created and that maybe the point that the car was trying to move to was at a point just below the wheels but the wheels would collide and thus it would stabalize at a distance. However, even this theory has alot of holes in it that makes me thing I’m wrong about it. T_T

  3. A sub point of this issue is that whenever my boat turned or even slightly ran into something, most often the traces holding it up would touch part of the wall and then it would start a chain reaction of increasing the height of my boat, making driving it in narrow spaces practically impossible. Obviously, this is similar to my current issue with Epic’s vehicle component as it is, but it was much more pronounced in the hovercar attempt.

  4. The hover car tutorial has the car being moved around by addforce, which is just fine and dandy if you don’t care about ignoring gravity or only having your car move when its wheels are on the ground. And unfortunately, I don’t have much of any other clue how you move physics objects around other than something like addforce.

Now, I know that I am talking alot about the hovercar tutorial and that a lot of the issues stem from how it is different from a regular car, but that is because I just don’t have any other place to start from. I haven’t seen anyone else give even a hint of a tutorial on how to make their own car blueprint instead of just using Epic’s. As it is, I am pretty much stuck and all I can do is either get help from someone here or be the lucky monkey that types out Shakespeare by banging on the keyboard long enough. :frowning:

And, of course, there is the issue that I seem to be completely inept at figuring out wtf is going on in blueprints unless I am following an exact tutorial. Just tried following/replicating what Pery77 showed on the Space Dust Racing blog here: Space Dust Racing (Unreal Engine 4) Arcade Vehicle Physics Tour - Space Dust Studios Which all looks great and like it would work. However, of course, in my own attempt to make it, I seem to put all the nodes and stuff together correctly (only so far as the hovering components) and guess what my biggest issue is… ding ding ding, if you guessed that my pawn won’t move, not for gravity, or addforce, or set physics linear velocity, or seemingly anything that has to do with physics. Oh, its accepting input, had to check that with a print string cuz there was no other way to tell. sigh Sorry for the short rant, just kinda wish things were easier to get going from the start, as some things just seem impossibly daunting in how mysterious they are to figure out what is wrong when everything seems to be in order.