Hello! Thank you both for the useful responses, I will definitely give a look st the RL examples first and then go more in depth with the Kart dynamics, Thanks again for the support,
On Tue, 26 Aug 2025 at 01:36, 'Radu Serban' via ProjectChrono < projectchrono@googlegroups.com> wrote: > Marco, > > > > To answer your actual question: not all suspension templates in > Chrono::Vehicle are **steerable**. ChRigidSuspension in particular > cannot be attached to a steering mechanism. This is because the topology > of the mechanical system described by this template simply does not provide > the necessary degrees of freedom for steering. This also means that this > suspension template is **not** appropriate for modeling your vehicle. In > other words, the front suspension mechanism on your vehicle has additional > bodies that are not part of the ChRigidSuspension template. Those bodies > are likely knuckles that provide the necessary steering DOFs and to which a > steering mechanism can be attached. You will need to figure out if there > is a more suitable suspension template in Chrono::Vehicle and use that, If > none is appropriate, you can model your own using an appropriate JSON > specification input file with the ChGenericWheeledSuspension (butfr that, > you must first understand the mechanism that you try to model). > > > > --Radu > > > > *From:* 'Harry ZHANG' via ProjectChrono <projectchrono@googlegroups.com> > *Sent:* Sunday, 24 August 2025 17:47 > *To:* ProjectChrono <projectchrono@googlegroups.com> > *Subject:* [chrono] Re: Steerable RigidSuspension > > > > Hey Macro, > > > > Regarding the RL part, in my mind, the most useful resource in this case > would be gym-chrono (https://github.com/projectchrono/gym-chrono > <https://urldefense.com/v3/__https:/github.com/projectchrono/gym-chrono__;!!Mak6IKo!I195JXvCiu22XYP4KMSqJpvJsjr7EHl3V2fyt0Er0w9HXnl8NXBm4uglv65acuSEVnVEa1iOzT65e0is97CvM7v-QkU$>). > Not sure what your RL policy wants to achieve, for instance, do you want to > train a vehicle agent doing trajectory tracking, or goal reaching with > obstacle avoidance, etc. But I would say the example existing in gym-chrono > repo could give you a jump start on this. Two things I want to highlight > about gym-chrono > > 1. It uses stable-baseline3 as RL algorithm library and gymnasium > environment. While you might choose other RL libraries, the example > provides a guide how to wrap up chrono physics engine as RL training > environment (gym environment) that has key functions such as step, > get_observation, etc. > > > 2. Check out the example > > https://github.com/projectchrono/gym-chrono/blob/master/gym_chrono/envs/wheeled/off_road_gator.py > > <https://urldefense.com/v3/__https:/github.com/projectchrono/gym-chrono/blob/master/gym_chrono/envs/wheeled/off_road_gator.py__;!!Mak6IKo!I195JXvCiu22XYP4KMSqJpvJsjr7EHl3V2fyt0Er0w9HXnl8NXBm4uglv65acuSEVnVEa1iOzT65e0is97CvvzLmhn4$>. > This setup an environment for Gator vehicle doing obstacle avoidance while > reaching target position, which utilize chrono's vehicle, sensor support in > the physics engine. I would recommend use it as template for setting up RL > problem with Chrono. > > > > Let me know if you have further questions. > > > > Best, > > Harry > > > > On Wednesday, August 20, 2025 at 1:09:33 PM UTC-5 marco.c...@gmail.com > wrote: > > Hello everyone I am quite new to Project Chrono so I might be missing > something, > > I am currently using pychrono to implement the simulation of a Kart to use > with a reinforcement learning agent to drive the kart. > > I was trying to implement front and rear ends as close to reality as > possible and for that I chose RigidSuspensions both for front and rear. > > At the front I implemented a RackPinion steering to emulate the Kart > steering system. > > > > With the double wishbone i was able to get the kart to run and steer > correctly in the simulation but when I implement the RigidSuspension it > does move the steering bar but does not rotate the wheels. Is the > RigidSuspension able to implement steering mechanisms? Do I just have to > change the connection positions? > > > > From the image you can see the steering bar moved according to the > steering input, but the wheels position remained untouched. > > > > If needed I can attach all my JSONs used for the configuration, > > > > Thanks in advance, > > > > > > -- > 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 projectchrono+unsubscr...@googlegroups.com. > To view this discussion visit > https://groups.google.com/d/msgid/projectchrono/ae5a96f5-cf27-420b-b071-efa0321fddcbn%40googlegroups.com > <https://urldefense.com/v3/__https:/groups.google.com/d/msgid/projectchrono/ae5a96f5-cf27-420b-b071-efa0321fddcbn*40googlegroups.com?utm_medium=email&utm_source=footer__;JQ!!Mak6IKo!I195JXvCiu22XYP4KMSqJpvJsjr7EHl3V2fyt0Er0w9HXnl8NXBm4uglv65acuSEVnVEa1iOzT65e0is97CvS_P8P7k$> > . > > -- > 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 projectchrono+unsubscr...@googlegroups.com. > To view this discussion visit > https://groups.google.com/d/msgid/projectchrono/CH3PPF46CDC2185ED19C63961E1A4F85BB1A73EA%40CH3PPF46CDC2185.namprd06.prod.outlook.com > <https://groups.google.com/d/msgid/projectchrono/CH3PPF46CDC2185ED19C63961E1A4F85BB1A73EA%40CH3PPF46CDC2185.namprd06.prod.outlook.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "ProjectChrono" group. 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