monocular-intertial added :D

[Tim-HW]

Hi everyone,

First off, a big thank you to the maintainers/contributors for the excellent work on this project – it's been incredibly useful!

I had a specific need for visual-inertial tracking using a single camera and an IMU, primarily to improve pose estimation robustness, especially during fast movements or in environments lacking distinct visual features.

To address this, I've implemented and added a monocular-inertial node to the package. It integrates the monocular camera feed with the IMU data. I've done some initial testing on [mention dataset type briefly, e.g., EuRoC dataset / my own robot], and the results look promising :D

Any feedback or suggestions would be welcome!

Cheers
Tim

[noah-curran]

Hey @Tim-HW , I gave your code a test on ROS2 Humble out of curiosity. A few comments:

1. The AI generated comments should probably be removed.
2. The camera topics in monocular-inertial-slam-node.cpp should be consistent with the other nodes.
3. The command-line args in mono-inertial.cpp are inconsistent with this library. (And, the usage printouts are just incorrect.)
4. After correcting above errors with command-line args, I am able to get it to successfully run for several frames before it Seg Faults. I checked your logic in SyncWithImu and it seems like you don't have similar error checking that is included in the same method in stereo-inertial-node.cpp.