Sigyn is like a fine whiskey now, it's smooooth

[Michael Wimble]



Last Tuesday's ROS SIG had some comments about how fast and smooth my robot, Sigyn, was in patrolling my house. Since then I've invested quite a number of hours in making it even better.

• I experimented with dual IMUs, mounted upside down relative to each other (rejected in the end and went back to using one).
• Added a second LIDAR. A lower LIDAR is used for the local costmap and obstacle avoidance, the upper LIDAR, which doesn't see table legs, boxes, etc., is used just for localization.
• Did a lot more tuning, especially AMCL.
• Did a lot of fixing of code in my three, custom Teensy 4.1 boards that drive my sensors and motors.
• Created a new test program to check out performance in a scripted movement, to see if IMUs and wheel odometry is behaving. You run it via 'python3 diagnose_localization.py' from my git repo.

My repo is at https://github.com/wimblerobotics/Sigyn

Things are working very nicely now. Very!

I may put together a new movie for next Tuesday's ROS SIG meeting, and may even show it at the next club meeting.

Meanwhile, I'm including two documents, which are in my repo (well, the markdown version is).

LocalizationAndSensorFusion.pdf -- captures a few lessons I learned along the way.

WhySigynMovesSoSmoothly.pdf -- what it says on the box.

[Thomas Messerschmidt]

Do you have any videos? 

Thomas

On Oct 10, 2025, at 7:13 PM, Michael Wimble <mwi...@gmail.com> wrote:



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<LocalizationAndSensorFusion.pdf>

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<WhySigynMovesSoSmoothly.pdf>

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[Sergei Grichine]

Wow, these two PDFs are a goldmine, Michael - thanks for putting it all together.

I need to reconsider some of my design choices and to have some measurements done on my bots. "What I think is good enough" sometimes isn't...

I always thought that smooth and confident movement is a holy grail of robotics, and it is hard to achieve without proper analysis. It's great to know what to pay attention to.

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Best Regards,

-- Sergei

[Michael Wimble]

Oh, the latest code is on the branch analysis_changes. I haven’t merged to main yet

On Oct 10, 2025, at 8:59 PM, Sergei Grichine <vital...@gmail.com> wrote:



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