What is the difference between Theta(r) and theta(0)

What is the difference between the bottom two variables, theta(0) and theta(r)?

Thanks for any help!

I could be misunderstanding this as there is very little context, but is it not defined right there? they just represent whatever theta was at two different points

In terms of context, this is from the Pilons odometry document from 2018.

Anyways, θ1 is the current absolute orientation each time through the loop. It is calculated by adding θr, the global orientation when you last reset the encoders, to the change in the orientation since the last reset, calculated with a formula as described later in that document. θ0 is the previous iteration of θ1, you can subtract them from each other to get ∆θ for the time since last update.


How does one reset the encoders?


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Alright, the algorithm doesn’t mention when to reset the encoders though, do i do it at the end of each iteration?

You do it whenever you hard reset the robots position, like ramming into a wall


Do you know other times in which resetting the position would be necessary? I don’t really understand what the importance of resetting the position is.

your measurements will drift over time, resetting them limits how much they can drift.

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