Polargraph Drawing Machine

Step 20 Now really make it move!

You need to calibrate the machine before each drawing session.  This involves telling it where the pen is.  You do this by clicking Set home on the Input tab and then physically moving the gondola so that it directly over the home point that you worked out earlier.

Clicking Set home locks the motors, it applies power, so they will hold the gondola there for as long as you want.

AND THAT'S IT!

Use Move pen to point to move the gondola around the drawing surface.  The noise should be smooth, and the motion also.  If you find your motors slip - most likely near the extremes of the the surface, or when you're moving fast - you'll need to recalibrate.  As soon as the actual position of the gondola gets out of sync with where the machine thinks it is, then your geometry is all off and your drawings will be distorted.

The standard maximum speed is 600 steps per second, and the acceleration is 700 steps per second (per second).  Change these values by using the number spinners on the setup tab, and then clicking send speed. You can also increment and decrement the top speed with + and -, and the acceleration with / and *, in blocks of 25.  These speed change commands also skip right to the front of the queue too - they're priority, you can see them in cyan in the queue.