TinySDP

Real-time semidefinite optimization for certifiable edge robotics.

TinySDP extends TinyMPC with small structured semidefinite relaxations, enabling obstacle-aware MPC to run onboard resource-constrained robots such as the Crazyflie 2.1 Brushless.

✅ Runs onboard at 25 Hz
✅ Supports PSD-relaxed obstacle avoidance
✅ Static-memory embedded implementation
✅ Hardware demos on Crazyflie
✅ Accepted to RSS 2026

Why TinySDP?

Robots running on small processors usually cannot afford generic semidefinite programming. TinySDP keeps the optimization structure small and fixed, so certifiable obstacle-aware control can run in real time without dynamic memory allocation or desktop-class hardware.

This repository contains the reusable C++ solver in include/solver and src/solver, plus three standalone TinySDP examples:

• ushape_demo: closed-loop 2D U-shape obstacle avoidance with rank-1 certificate logging
• sweeping_gate_3d_demo: 3D sweeping gate
• rising_gate_3d_demo: 3D rising gate

Dependencies

• CMake 3.15 or newer
• A C++17 compiler
• Eigen 3
• Matplotlib for plotting example outputs

On macOS with Homebrew:

brew install eigen cmake
python -m pip install matplotlib

Quick Start

cmake -S . -B build
cmake --build build

Run the demos:

./build/examples/ushape_demo
./build/examples/sweeping_gate_3d_demo
./build/examples/rising_gate_3d_demo

Example CSV outputs are written to outputs/ by default. Set TINYSDP_OUTPUT_DIR=/path/to/output to write them elsewhere.

The U-shape demo defaults to the inside-the-cul-de-sac start. Other starts are available with:

./build/examples/ushape_demo --start edge_up
./build/examples/ushape_demo --start edge_down
./build/examples/ushape_demo --start outside_center
./build/examples/ushape_demo --start above
./build/examples/ushape_demo --start below

Plot any generated trajectory CSVs:

python scripts/plot_examples.py

The plotting script scans outputs/ and writes trajectory PNGs to outputs/plots/. Use --input-dir or --output-dir to override those paths.

Project Layout

• include/solver: public solver headers
• src/solver: solver implementation
• examples: TinySDP-only demos
• scripts: plotting and utility scripts
• assets: README media

Getting Help

Open a GitHub issue for bugs, build problems, or questions about the examples.

Maintainers

TinySDP is maintained by the Accessible and Accelerated Robotics Lab (A²R Lab).