For my drivetrain for Push Back, I have two odometry pods. One horizontal, and one vertical. I was wondering if its ok just to go one vertical pod because I need the extra space on the drivetrain so I can mount the airtank as low as possible.
It is okay, but you need to run traction wheels. I’d also looking into distance resets. I ran just one vertical and it worked fairly well however the robot sideways drift was an issue because I couldn’t detect it. So it works, but two is way better. Even with distance resets unless are you doing MCL it still might not detect all drift.
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It is possible but you need to consider horizontal drift. Are you planning on using any traction wheels? Because if you’re using all Omni I wouldn’t recommend it with pure odometry
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You should try to go with two pods and the air tank.
You will be surprised how much stuff you can squeeze into the chassis once you start thinking outside of the box.
I am using 4 omni wheels, no traction. I saw for 229v’s robot for worlds, they had all omnis and just a vertical odom pod.
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Yes, but they were likely using things like limiting acceleration and optimizing their curves so the robot didn’t drift much. I wouldn’t have been surprised if they also had distance sensors on there, but I’m not sure about that.
You can use one wheel, the result just won’t be nearly as good, and for me was way worse than two.
Yeah as I was saying it is definitely possible, just much harder with all Omni. You would neither have to accept horizontal drift which causes inconsistency between runs, move in Mays that reduce drift like not turning quickly or smth, or some more advanced things like filters or things like that.
I haven’t personally done too much with this but you could experiment with Odom resets. The way I did this (very basic but worked fine) is by having a couple distance sensors on sides of the robot. You could do like front and right, or all sides if needed it really depends.
Then after maybe a quarter of your code (for skills, qual doesn’t need a reset) or whenever easiest you would (using the inertial sensor) turn perfectly sideways and measure the distance the the front/back wall. Then turn forwards and measure to the left/right wall.
After that you just subtract that distance (in mm so convert to inches) from the max field size and set those values to your Odom position.
This essentially just resets the Odom position after a certain amount of time to minimize drift. Lmk if you want a more detailed explanation and I can share some of the code
Theoretically, this is even possible with only drivetrain encoders but it would need reset much more often. I’m not sure how much time your willing to put into this but you could experiment with dynamic or automatic updating. By this I mean it automatically resets no matter what angle your facing, but this uses a lot of trig and more advanced coding but would be a fun project.
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That would be viable, but I just started coding with pros. For when I rebuild(Prob in October) ill probably implement a barking system and traction wheels.
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