Re: Unexpected Behavior and Results

Home Evil Mad Scientist Forums WaterColorBot Unexpected Behavior and Results Re: Unexpected Behavior and Results

Windell Oskay
Can you tell if the problem is one of software or mechanics?  In other words, is it genuinely correlated to how complex the drawing is?  (And if so, which software are you using?)  Can you clarify exactly what is happening when it “loses location for a second?” You said that you can hear it, so that suggests that you’re hearing cogging, or something similar is happening– please elaborate, so that we can help correct the situation.
If it is a software issue: There is a known problem in the previous release of RoboPaint (v 0.6.4) that would cause seemingly random lines to appear when the file was too complex.  (See here fore more info: ). If this looks like what you are seeing, and you are using RoboPaint, please make sure that you’re using the latest version (0.7.0).
If it is a mechanical issue: Once the WaterColorBot is properly tuned, it will not lose steps anywhere.  (And once it’s tuned, it should *stay that way* for months on end.)  So, check the steps that we listed above, and make sure that the motor current is appropriate.  
For what is “appropriate,” please read the link above about adjusting the motor current– we have a lot of hints and advice there.  If the current is too low, the motors will be weak, and you’ll get cogging, resulting in a loss of position.  (It will not burn out the motor.)  If the current is too high, the motors will be hot, jerky, and noisy.  There’s always a “goldilocks zone” in the middle.
The method of re-calibrating in the middle of painting depends on which software you’re using.  For example, in RoboPaint RT, pause the painting, click Motors:Off (to turn off the motors), manually move the carriage to the home position, click Motors:Zero (to declare that the carriage is in the home position), and resume.