Russ Tedrake

> Sometimes, the discretion distance `s` can be varied based on the properties of the region (for instance, the maximum distance). `s` should always be in [0, 1], so this...

Thanks @cohnt for the summary. > We would check that the given costs and constraints matched the number of variables in a given vertex/edge, although down the line, we could...

> is the idea that we would have a method like GcsTrajectoryOptimization::Subgraph::GetPlaceholderXu which effectively plumbs through GraphOfConvexSets::Vertex::x() for a generic instance of a vertex within the subgraph? That's exactly right....

Let's see. `Subgraph` is an abstraction on top of a `Vertex`, but with a particular ordering of the variables. `EdgesBetweenSubgraphs` generalize the `Edge`. For the names, I would match `KinematicTrajectoryOptimization`...

I think there is a case for having specific entry points for making generic position and generic velocity constraints (e.g. applied to all knot points in a vertex) because that...

We also have a rough draft of how we were hoping to use it [here](https://github.com/rhjiang/drake/blob/95fd539b08fdc10e70926565edcdf1f9ec02397d/geometry/optimization/iris.cc#L543-L556); from [this branch](https://github.com/RobotLocomotion/drake/compare/master...rhjiang:drake:ray_iris).

It's a nice point. But I think it's pretty rare that we would have lower bounds on acceleration/jerk w/o the corresponding upper bounds?

Oh, great news about the license! Re: merging the geometries; the output from the blender conversion worked (it loaded as a single object) without any additional modifications required.

What about something in between: (1.5) We provide a python script like `prepare_model_for_drake.py` which crawls the urdf, sdf, mjcf, and automatically converts dae and stl files, etc. I think this...

Update: I've ported @wrangelvid 's latest and greatest [uav example into the underactuated repo](https://github.com/RussTedrake/underactuated/blob/09da23e40591640c4709139a39b00320b59cbca3/book/trajopt/gcs_quadrotor.ipynb), where I will continue to nurture/maintain it. We're just missing the energy costs (really derivative costs)...