lucasw

AMP with Carter Schultz - Rust in Production Podcast | corrode Rust Consulting Imagine you’re faced with the challenge to build a system that can handle billions of recyclable items per year with the goal of being better than a human at identifying what can be recycled. Material...

Rust in Production robotics podcasts in addition to the Scythe Robotics with Andrew Tinka one above: Matic with Eric Seppanen and AMP with Carter Schultz:

corrode.dev/podcast/s02e...

corrode.dev/podcast/s02e...

Scythe Robotics with Andrew Tinka - Rust in Production Podcast | corrode Rust Consulting Building autonomous robots that operate safely in the real world is one of…

corrode.dev/podcast/s05e...

"I I think it gives people an idea that we're like a Montessori school for systems people. And it's like hey everyone come in and just do whatever you want. Do you wanna eat the Play Doh today? Ok eat the Play Doh... I feel like that's not really accurate"

"We can talk about this in kind of our founder mode episode that we about the importance of trust and clarity. And if you've got trust and clarity, then I think you can have autonomy... I think autonomy is important because I think that's when people do the best work"

Release 5.4.0 · jrouwe/JoltPhysics There are a few minor breaking changes, see this document. New Functionality Added Cosserat rods to soft bodies. This is a stick constraint with an orientation that can be used to attach geometry....

Jolt Physics v5.4.0 is out! Check out the release notes here: github.com/jrouwe/JoltP...

YouTube video by Lucas Walter Rust Bevy JoltPhysics vehicle simulation

Rust wrapped Jolt Physics visualized in Bevy- each ray-cast simulated lidar point is an individually translated sphere
youtu.be/I2yfPAyACps?...

YouTube video by Jon Gjengset Sguaba: Type-safe spatial math in Rust

About a month ago, I gave a talk at the Rust Amsterdam meetup about Sguaba (the type-safe spatial math Rust crate), and the recording of that is now online for anyone who wants their head to hurt with frames of reference and coordinate transforms 😅
youtu.be/kESBAiTYMoQ

The 'Rust for Robotics' video is now on youtube: youtu.be/1zLLuWbnuN8?...

It's been a month since #rustconf 2025, but the buzz is still strong! 🦀

Revisit the magic via these videos on the @rustfoundation.org YouTube channel, incl. sessions, keynotes, & this highlight reel: www.youtube.com/watch?v=Hw_I...

+Don’t miss these event pics 📸 www.flickr.com/photos/rustf...

A nice feature with rerun with the buffering of recent data in rerun is that I can build, run a simulation of so many steps faster than real time, replay some then make changes and recompile, but continue to watch the sim in rerun and scrub around in time while waiting (and maybe make more changes).

@rerun.io for visualization again, though the movement over the terrain is not obvious- directional lighting and shadows would help (rviz doesn't have shadows but does have camera aligned lighting). I could bake some shading into the mesh triangle colors, or other rerun features could help?

The Jolt Physics 'VehicleConstraintsTest C++ wrapped in rust using cxx- it's working as well as I need it to though I'm not sure if wheel friction is right (are wheels spinning faster than vehicle speed over the ground?). The build process isn't ideal but is workable.
github.com/lucasw/jolt_...

A soon-to-be-released book about iRobot: 'Dancing with Roomba: Cracking the Robot Riddle and Building an Icon' dancingwithroomba.com - via @weeklyrobotics.bsky.social (www.weeklyrobotics.com)

```
cxx_build::bridge...
.define("JPH_DEBUG_RENDERER", Some("1"))
.define("JPH_PROFILE_ENABLED", Some("1"))
```

Now can run the hello world through cxx, can resume with the vehicle example next

Need to match these:
```
Version mismatch, make sure you compile the client code with the same Jolt version and compiler definitions!
Mismatching define JPH_PROFILE_ENABLED.
Mismatching define JPH_DEBUG_RENDERER.
```

Include headers in cxx_build include() brought in by a dependency within target/ sub-directory? · Issue #1641 · dtolnay/cxx I have headers like target/release/build/joltc-sys-cbcdf0340a740e35/out/include/Jolt/Physics/PhysicsSystem.h I'd like to use with cxx_build::bridge(...).include(), but that hash is not going to be ...

Maybe will get an answer here github.com/dtolnay/cxx/... though it isn't really a cxx issue

Does 'links' help? doc.rust-lang.org/cargo/refere...

First question is can I use header files that are pulled in by a dependency (joltc-sys) in my `build.rs`? It looks like it automatically knows about target/release/build/joltc-...hash.../out/lib/libJolt.a, I can link that, but how to include 'joltc-sys-.../out/include/' in cxx_build?

Starting over with getting a Jolt physics vehicle simulation into rust- going to try to put a big chunk of it into C++, then use cxx to manage that through a high level interface to supply inputs, step the sim, and get new state after the step update.

The next thing needed is a HeightField to drive over, but that isn't in the jolt-rust JoltC currently- github.com/amerkoleci/j... which is a different jolt c wrapper does have it, but making a rust wrapper for that is daunting. Should I just do nearly everything in C++, wrap in rust at high level?

Have a sim vehicle in jolt-rust working with stacked hinges for wheel rotation and steering on two of four wheels, no suspension, visualized in @rerun.io:

But now I'm seeing the SixDOFConstraintSettings is missing the MotorSettings... maybe I should just make slider constraints and add separate steering and rolling hinges?

What about GroupFilterTable? I see JPC_GroupFilter but no table- what does the table do?

But VehicleSixDOFTest.cpp only needs SixDOFConstraintSettings which is already in JoltC, so that's the example to follow for now

Now looking at VehicleConstraintTest.cpp there are several things that don't exist in JoltC: VehicleConstraintSettings & WheelSettingsWV (which extends WheelSettings) - the first looks to be easy to add, there are many other *ConstraintSettings in JoltC to follow the example of.

Rustconf main room

add PhysicsSystem SetGravity · lucasw/JoltC@5f08a55

Also need to update the joltc submodule with SetGravity: github.com/lucasw/JoltC...

add physics system set_gravity · lucasw/jolt-rust@ed21aad

Have to cargo clean if I add a new function to the Jolt bindings? Or is there a specific file or directory in target I could have deleted for less rebuilding time?

Anyhow added SetGravity()

github.com/lucasw/jolt-...

cargo test is very sensitive to the link order (on linux), it has to … · lucasw/jolt-rust@94efc77 …be in this new position

cargo test was strangely sensitive to `build.rs` link order, figured it out by trial and error: github.com/lucasw/jolt-...

linux building is current of jolt-rust was broken, `undefined reference to `JPH::AlignedFree'` and many many others- but adding a `build.rs` to link the built libraries in the hello world examples fixed that- except cargo test has the same problem- how do I link it?