research
Research
and Publications.
π IEEE CASE β August 2025
cHyRRT and cHySST: Two Motion Planning Tools
for Hybrid Dynamical Systems
view paper β
REU Researcher β RoboLand Lab, USC
Problem Statement
Locomotion on deformable terrain, where robotβterrain motion coupling occurs, remains a gap in existing literature. Discrete probe-then-decide traversability strategies and deployment of legged robots in obstacle-dense environments like substations and construction sites, raise a further question: Can a robot successfully exploit a yielding obstacle field?
Methodology
At small-to-moderate deformation, yielding terrain behaves approximately like a spring. This motivates a spring loaded obstacle model. We designed and prototyped a novel locomotion test bed with spring-loaded obstacles mounted on a custom sliding mechanism to enable repeatable trials. Trials over variable obstacle spacings and stiffnesses with a caterpillar-inspired robot yielded observed trends in obstacle stiffness/spacing and traversal robustness.
Institution / Lab
RoboLand Lab, USC
Dr. Feifei Qian
Skills Practiced
Presented At
Materials
Research Intern β LILAQ Lab, Harvey Mudd current
Problem Statement
Project 1:
Communicating realtime, hyperlocal air quality is difficult with legacy sensor middleware and fragmented data pipelines.
To inform the local community of air quality information distilled from an array of research-grade sensors,
the Lab for Investigations of Local Air Quality (LILAQ) needs reliable, real-time meteorological data collection infrastructure.
Project 2:
Additionally, indoor COβ levels impact occupant focus, alertness, and long-term health. However, popular commercial COβ indicators
can cost upwards of $200.
Methodology
Project 1:
Wrote BASH and IGOR scripts
for Raspberry Pi and Windows devices to stream data to Firebase from PurpleAir and
meteorological sensors on legacy middleware.
Project 2:
Prototyped a COβ indicator with I2C interface to SCD41 sensor. Designed sensor enclosure in SolidWorks
using edit-in-context assembly workflow.
Institution
Lab for Investigations of Local Air Quality, Harvey Mudd
Dr. Julie Medero and Dr. Lelia Hawkins
Skills Practiced
Research Intern β Hybrid Systems Lab, UC Santa Cruz
Problem Statement
Standard motion planners are designed for smooth continuous systems and fail on hybrid dynamical systems β those with both continuous flow and discrete jumps (e.g. a quadcopter bouncing off walls, a ball bouncing on a floor). No tools existed in the Open Motion Planning Library (OMPL) for this class of systems.
Methodology
Implemented cHyRRT and cHySST β two novel motion planners based on RRT and SST respectively β extended to handle hybrid dynamical systems with resets. Validated on collision-resilient quadcopter, bouncing ball, and pinball machine models. Results published and presented at IEEE CASE 2025. Both planners were accepted into OMPL.
Institution / Lab
Hybrid Systems Lab, UC Santa Cruz
Dr. Ricardo Sanfelice
Skills Practiced
Presented At
IEEE CASE 2025
Materials