a weird bug encountered in an old project

[katron]

Hey everyone,

I got a bug report from a user which uses our simulator (which is made approximately 7 years ago with leadwerks) and it is giving me hard time to find out the source. I thought maybe some of you guys can put me into right direction.

 

First of all, i didnt write a single code line to this project and people who did this is not around here for a long while. So i am all alone in this mess.

 

Project includes a truck which can hitch 3 different types of trailers. According to the scenario the driver will pick some of those trailers and get some stuff from the plane and put them into the storage building.

These 3 different trailers are named, BaggageTruck, TrailerDolly and ContainerDolly.

 

If you drive the vehicle without any trailers hitched, the vehicle keeps it max velocity 28km/h as it is supposed to do.

 

However, when i hitch the first trailer(BaggageTruck) when moving in -X direction the vehicle can go up to infinite speed (limited to the map size) with an exponential velocity graph. (I mean at every direction from 0 to 180 angles in X-Y axis)

 

With 2nd trailer(TrailerDolly) the vehicle behave the same at the opposite directions(+X) (from 180 to 360 in X-Y axis)

 

with 3rd trailer(ContainerDolly) the vehicle behave the same with "BaggageTruck"

 

The map is all flat. 0 difference in z direction.

And when i hitch the TrailerDolly and ContainerDolly together, the vehicle speed is not capped to 28 km/h for +X direction but with a much smaller acceleratio in the given map. Tho it can go up to the same values in a much larger map.

 

I ve done a lot of tinkering with the classes and phy files. The only thing that gets me closer to solution is following:

When i change the RollingResistanceCoefficient from 0.1 to 0 in BaggageTruck .phy file, the trailer(BaggageTurck) is working as intended. The same thing doesnt solve the problem for the other 2 trailers which is just stupid imo.

 

 

It is already too long for a post, so i am cutting this here. But if some of you guys need some further information to help me out, i will be around here to give you as much info as i can give.