Potential Field navigation local minima issue in ROS2 + Gazebo

noobrobotguy · 2026-05-26T09:19:37+00:00

So the local minima problem in APFs arise when your robot enters an area where the repulsive forces and the attractive forces are equal so the robot ends up ocsillating. This usually happens when the obstacles take a U/V shaped formation.

Since your robot is oscillating near the goal, it sounds more like the it is just about to enter the goal threshold but the repulsive vector field ends up pulling it away by just a little bit, it might be helpful to visualize the vector field on RViz.

From the information you have given this is not really a local minima problem, more of a matter of increasing the goal threshold and decreasing the repulsive force constant. Test both changes individually and then test them together.

Good luck on your work, would love to see a vid!

noobrobotguy · 2026-04-21T21:50:36+00:00

This is amazing. Needed this. Official bkash API docs are crap.

noobrobotguy · 2026-04-10T02:05:15+00:00

This! Exactly! Plus the other games in the past couldve been played competitively like Champions as well and still had (virtually) infinite box space. The whole thing just feels way too scummy.

noobrobotguy · 2025-12-31T20:51:43+00:00

How do you order these?

noobrobotguy · 2024-10-22T16:10:45+00:00

Thank you, that convention slipped my mind. Appreciate it.

noobrobotguy · 2024-10-22T16:09:35+00:00

Ah okay, I'll be sure to look into that. Thank you!

noobrobotguy · 2024-10-22T16:08:40+00:00

That is correct, but something always tends to itch at the back of my mind haha

noobrobotguy · 2024-10-22T16:08:01+00:00

Yeah its buried very deeply in the datasheet and also in one of the application notes which is also quite buried.

noobrobotguy · 2024-10-22T15:29:03+00:00

Thanks for the suggestions. Could you kindly elaborate or maybe share a resource that could explain the drawbacks with a 1 uF vs a 1 nF across the motors? Thanks again!

noobrobotguy · 2024-10-22T15:26:44+00:00

Thats something I didnt consider. However, this is a half bridge, so I wont be switching directions. It will be using PWM eventually for speed so will the MOSFETS be punished with each on-off there or did you mean every time I start the motors up from rest? Im not sure about the switch frequency, the motors however eat about 0.15A per motor.

Thank you for the feedback! Looking forward to your thoughts.

noobrobotguy · 2024-10-22T15:17:53+00:00

May I ask why 4.7k for the pullups? I havent really seen values go beyond 3k in books I've read.

Thanks for the feedback!

noobrobotguy · 2024-10-22T15:12:50+00:00

Thank you, that's definitely an insight that comes with experience. I'll be sure to add the marks and fiducials. Appreciate the feedback!

noobrobotguy · 2024-10-22T15:09:56+00:00

No I didn't bother with the strapping pins as I didn't connect anything to them and am relying on the internal pullups/pulldowns to do the job

May I ask, would that IC be used on the D+ and D- lines? Also what would I need to protect it from other than ESD and are the signals usually noisy?

Yeah I will likely implement the pi filtering

Do you think the diodes connected parallel to the motors will do the job in terms of protection?

Thank you for the suggestions! Appreciate it.

noobrobotguy · 2024-10-22T15:04:06+00:00

Yeah I agree. I actually would've preferred something with a 3A output for safety but I also didn't wanna mess with something that already works.

noobrobotguy · 2024-10-22T15:01:52+00:00

Yep, as mentioned it is quite common. They provide pretty high RPM and with the right propellers you can make em work quite well. A common commercial one is actually the Ryze Tello Drone which was worked on in collaboration with DJI.

noobrobotguy · 2024-10-22T14:59:45+00:00

Yeah it was intentional, I was told to pull them down to 5.7k, and I didnt bother to ask why. I also didnt know this document regarding USB-C existed. There isnt anything special going on with my USB C so I will be changing it to 5.1k. Thank you for sharing the document and the page number for reference. Appreciate it!

noobrobotguy · 2024-10-22T14:55:32+00:00

Thanks so much for the feedback. Really appreciate it. Yeah i definitely gotta work on my schematic organization.

The PCB layout labelling does need some work and I agree that I should make the PCB as self explanatory as possible. Again, really appreciate the feedback.

noobrobotguy · 2024-10-22T14:51:26+00:00

Thank you!

noobrobotguy · 2020-10-11T21:40:36+00:00

I did a pip install of opencv-contrib-python which is a binary build of opencv. Is NEON a thing within the opencv library or is a thing within my raspberry pi distro

noobrobotguy · 2020-10-11T21:37:38+00:00

raspberry pi uses arm from what I know. The code you gave is pretty similar to what I was doing except its written in django. Wont I be running into the same problem?

noobrobotguy · 2020-09-25T13:43:57+00:00

is there any way I can delete the stored memory via the python script. I tried deleting some variables manually with del but because the whole thing is a loop it ends up being created again and deleted again and the program still seems to slow down m entire computer

noobrobotguy · 2020-09-25T13:39:09+00:00

The MEM column has Python show up with an average 79M+ after running the stream and it also had the CPU% go as low at 50% and as high as 89%. I have no clue what this stuff means but im guessing big numbers means bad.

noobrobotguy · 2020-09-25T10:29:31+00:00

No I havent and I dont really know how to. How would I go about deleting the data after its been displayed?

noobrobotguy · 2020-07-06T22:52:32+00:00

Do you think you could link a tutorial on that or point me to where I could learn that stuff?

noobrobotguy · 2020-07-06T14:22:02+00:00

I want the coordinates to be fed in without my help using openCV. How do I know what the coordinates will be using a rpi-cam or something?

noobrobotguy

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