Unsolvable issues with farmbot movements (x-axis)

Hey Guys,

since I have my farmbot, I fight with movement issues. Mostly x axis related.
It feels like I tried everything that is mentioned somewhere and that could be a possible root cause.
I made a video to show what I mean: https://youtu.be/IK32_o-Qb8w

I bought a regular farmbot and made it to the size of the new XL version. I used the exact same profile as you guys have sent me to make it longer and the same timing belt.
At first I tried to get the x axis profiles aligned on wood. Now I have exchanged it with some precise and bigger aluminium profile to be sure they really are in a straight line and also parallel to each for other the whole lenght of the x axis.
Also I tested various tensions of the timing belt and I checked the tension of the v-slot wheels several times. As I had to exchange the energie chain to a longer one, I tested without the chain to reduce friction. Also I checked the lenght of the y axis and played around with that.
I use the farmbot very off grid with solar power and two 100Ah batteries, so I thought maybe the voltage drops below the 12 V and then the motors have not enough power, I checked that, it’s somewhere like 12,5V at the farmbot. Should be enough I guess. Also I played around with the stepper driver current setting. Whatever I have done, it still is the same.
Z and Y axis move just fine, and when the x axis is already moving it mostly keeps moving without issues. The worst is when both axis are moving at the same time, as in the video, then they start over and over again and after several attemps they either keep moving or farmbot throws an error. I can’t finish to water all plants this way, because at some point it get’s stuck.
This really drives me mad, I need it to get moving properly otherwise I cannot use the farmbot
Hope for some good Ideas
Cheers
Paul

Try reducing the max speed. As you’ve noticed, only moving one axis at a time also helps.

Oh I forgot that, yeah I reduced max speed to 400 already. I even tried 300. No change

What do you mean by

As you’ve noticed, only moving one axis at a time also helps.

What is the relation between speed and the number of axis moving? Power consumption? Vibration?

There are likely several factors contributing to the issue, another one may be controller performance. Vibration may be an important one in your setup; you can try reducing the number of steps used for acceleration to close to zero (or 0, to disable acceleration). Or reduce the max speed to around 100.

With speed ad 300 and acceleration at 0 it seems to work stable. So finally I can use the farmbot :slight_smile:
Next step is to get it faster, but not the speed of movement, but the order of plants being watered is the bottleneck. As far as I now there is only the MLH farmware as a solution to water all plants, right?
So it’s a MLH development task kind of thing