Benjamin Chung
Benjamin Chung is a modeling & simulation consultant with JuliaHub. Previously, he was a postdoc at the University of Washington with Behcet Acikmese working on aerospace trajectory optimization after finishing his PhD with Jan Vitek on type systems for Julia.
Sessions
We present OptimalUncertaintyQuantification.jl: A SciML package for end-to-end distributionally robust uncertainty quantification of static and dynamic systems models. The tool performs a worst-case analysis so as to make certification/decertification decisions on engineering models defined in ModelingToolkit.jl as demonstrated on a variety of aerospace and structural engineering applications.
Julia can run fast on a desktop, but can it run fast --- and more importantly, reliably --- on an embedded platform such as a small application-class processor or even a microcontroller? Yes! We use Julia, integrated with PX4, to perform translational and attitude control of a quadcopter in a 1kHz closed loop. We show the compilation and deployment pipeline for running Julia on a CM4 companion computer, connected to PX4 via ROS.
Discrete models and control systems go hand in hand with continuous-time controls: many physical systems show state-dependent or discrete behavior such as clutches or friction, while realizable digital control systems are intrinsically discrete time. We describe the integration of synchronous systems - systems that execute in discrete steps on clocks or events - with ModelingToolkit to provide easy and compositional handling of discrete systems in high-level models.
Kerbal Space Program (KSP) is an entry point for many to aerospace as an easy-to-use, understandable way to build and fly flying machines. The community mod KRPC is then a gateway to automatic control of said vehicles, allowing external software to integrate with KSP to control spacecraft. KRPC.jl is an interface library to KRPC, allowing Julia software to control Kerbal rockets; we describe its architecture, use, and show an application where we use Julia to land an orbital rocket.
Aerodynamically-controlled vertical takeoff vertical landing reusable space launch vehicles are of considerable commercial interest. We built a reusable launch vehicle model with aerodynamic and propulsive controls, performed trajectory optimization, and developed an algorithm for approximate nonlinear reachability analysis of the system to identify safe re-ignition points.