dcsam

This library, built using GTSAM, provides factor type definitions and a new solver to perform approximate inference on discrete-continuous (hybrid) factor graph models typically encountered in robotics applications.

NOTE: As of 3/01/2026 the latest version of DC-SAM on main depends on GTSAM develop

Thanks to Varun Agrawal for bringing DC-SAM up to date with GTSAM.

If you are using GTSAM 4.1.1, check out our pre-4.2 release tag. This is the version of DC-SAM you would have used if you cloned the repository prior to 1/30/2023. Many thanks to Parker Lusk for bringing us into the future.

References

A technical report describing this library and our solver can be found here. If you found this code useful, please cite it as:

bibtex
@article{doherty2022discrete,
  author={Doherty, Kevin J. and Lu, Ziqi and Singh, Kurran and Leonard, John J.},
  journal={IEEE Robotics and Automation Letters},
  title={Discrete-{C}ontinuous {S}moothing and {M}apping},
  year={2022},
  volume={7},
  number={4},
  pages={12395-12402},
  doi={10.1109/LRA.2022.3216938}
}

Prerequisites

GTSAM @ develop

To retrieve the appropriate version of GTSAM:

sh
~ $ git clone https://github.com/borglab/gtsam
~ $ cd gtsam
~/gtsam $ git checkout 4.2a8

Follow instructions in the GTSAM repository to build and install with your desired configuration.

Optional

gtest for building tests.

Building

Building the project

To build using cmake:

bash
~/dcsam $ mkdir build
~/dcsam $ cd build
~/dcsam/build $ cmake ..
~/dcsam/build $ make -j

Run tests

To run unit tests, first build with testing enabled:

bash
~/dcsam $ mkdir build
~/dcsam $ cd build
~/dcsam/build $ cmake .. -DDCSAM_ENABLE_TESTS=ON
~/dcsam/build $ make -j

Now you can run the tests as follows:

bash
~/dcsam/build $ make test

Examples

For example usage, check out the DC-SAM examples repo or take a look through testDCSAM.cpp.

Developing

We're using pre-commit for automatic linting. To install pre-commit run:

sh
pip3 install pre-commit

You can verify your installation went through by running pre-commit --version and you should see something like pre-commit 2.7.1.

To get started using pre-commit with this codebase, from the project repo run:

sh
pre-commit install

Now, each time you git add new files and try to git commit your code will automatically be run through a variety of linters. You won't be able to commit anything until the linters are happy with your code.

Dcsam