Thanks Radu, I'm making progress. and am using the pre-built pychrono builds from here on windows. https://anaconda.org/projectchrono/pychrono/files/manage. I fought with installing C++ and could not get it to work on my system.
It seems like AddForce/AccumulateForce are not exposed in the build I installed (py313h84d2775_6211). I looks to me that this is the latest Windows build there. You mentioned I should get the latest code as there have been updates. Which one should I use? Thanks a lot, Dave. On Tuesday, November 11, 2025 at 4:18:18 AM UTC-5 Radu Serban wrote: > Hi Dave, > > > > I’m not sure what you mean by “bolting” together parts. The template-based > approach adopted in Chrono::Vehicle does allow building vehicle models from > parts, but with an assumed topology. > > > > If you are willing to build the entire vehicle (which, I assume, has 2 > track assemblies) just use the existing templates for a tracked vehicle. > You can then force it to go in a straight line using, if necessary, a > lateral controller. Depending on the construction of the vehicle you want > to model, you may need to define new templates if the existing ones are not > appropriate. > > > > If you only want to model half of the vehicle (although it’s debatable if > that is enough for the scenarios you are interested in), then look for > inspiration at the implementation of the track test rig > <https://github.com/projectchrono/chrono/blob/main/src/chrono_vehicle/tracked_vehicle/test_rig/ChTrackTestRig.cpp> > > (which effectively constructs a vehicle with one track). > > > > In either case, unless you can use the existing templates to model a full > vehicle, this involves some extensions of the existing Chrono::Vehicle > code. That is much easier to do in C++ since the Python wrappers are not > really meant for that. If possible, I also suggest you use the latest code > in the main branch of the Chrono git repository (since there were > significant changes from the 9.0 release). > > > > Radu > > > > *From:* [email protected] <[email protected]> *On > Behalf Of *David Morrill > *Sent:* Thursday, 6 November 2025 16:36 > *To:* ProjectChrono <[email protected]> > *Subject:* [chrono] Custom vehicle - snowmobile chassis guidance > > > > Hi, > > Newb here. My goal is to develop a snowmobile chassis using the > chrono:vehicle as a basis. I'm in Windows using an anaconda installation > with pychrono 9.0.1. It doesn't need to turn, just analyze straight bumps > and model acceleration/traction in a straight line and the reaction to the > variations on the chassis design. Almost a "2D" analysis. > > I think I may be not understanding a fundamental concept. I thought I > could just "bolt" together parts from the tracked and wheeled vehicles and > be good to go. > > > > Attempt A. > > I've tried to model a single sprocket, idler and road wheel with a track > using the M113_TrackAssemblySinglePin_Left and chassis, with limited > success. The next step would be to replace the M113 Linear Damper > Suspension Left with links/etc from the road vehicle to model a 4 link > type. I've tried 2 ways, creating/editing the JSON files from the demo, > and also tried to just instantiate M113 parts (road wheel for example) on > their own without an assembly or JSON. > > Attempt B. > I've also tried to model it with just physics with cylinders for wheels > and a segmented track. Modeling the track as segments and getting the > links to stay together hasn't worked yet, they "explode" when I apply > torque. > > Just looking for some guidance on which way is the best path forward. > I've been looking through the forums it seems like B may be better, but I > need some help/guidance. > > > > Recommendations from anyone are welcome. > > > > Thanks a lot, > > Dave. > > -- > You received this message because you are subscribed to the Google Groups > "ProjectChrono" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion visit > https://groups.google.com/d/msgid/projectchrono/453ff6eb-1e80-45d1-828c-c0fc5dd24044n%40googlegroups.com > > <https://urldefense.com/v3/__https:/groups.google.com/d/msgid/projectchrono/453ff6eb-1e80-45d1-828c-c0fc5dd24044n*40googlegroups.com?utm_medium=email&utm_source=footer__;JQ!!Mak6IKo!JivSJlCNU73gQ-KSwUaxg5OAawaDJ0xcIXiC0cqBSHpQJkzAOUPJ4QisadMUDlz0mOrREhseMHZLoA$> > . > -- You received this message because you are subscribed to the Google Groups "ProjectChrono" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/projectchrono/4b083f32-df15-49c5-938a-d7c2f02a0ac2n%40googlegroups.com.
