Can it be used to press keys on a keyboard?

dg1

I just saw this device today. I want one for a different purpose than writing. I want it to press keys on a keyboard with an empty "pen" and optionally to slide the same pen over a trackpad to move a mouse. The keyboards that I use are flat and exactly 11 inches wide, which is the X-range of the device. The other range of the device is 8.5 inches which gives me precisely enough space to put a trackpad under the keyboard. It's highly serendipitous in that regard (a perfect fit). I will do my best to try to find a way to make my own "subroutines" so that, for example, I can call one called PressA() and it will go press the A key. Has anyone done anything like this already, or am I solving a novel problem here? If I'm the only person with this problem, I will invent my own software to make this work, but if someone has done this, please tell me.

Windell Oskay

Can you please say which device you are asking about?

dg1

Sorry! Axidraw.

Windell Oskay

(I've moved this to the AxiDraw forum.)

The AxiDraw normally does not apply downward pressure -- it allows a pen to fall under its own weight. That's likely not enough pressure to activate the keys on a mechanical keyboard.

We've done a demo once with the WaterColorBot (another machine of ours), detailed here, holding a stylus. If you're using a capacitive-sensing trackpad (the most common type), you'll also need to add a ground connection to your stylus. (There's a ground tap available at the pen-lift servo, so it's quite possible.)

dg1

I see your point (no pun intended), but many modern keyboards require very little pressure to press a key. I can just use a pen heavy enough to press a key but light enough to be lifted by the Axidraw vertical servo. I just did a test with some quarters, and 1.5 ounces worth of quarters depresses a key gently. I suspect that the Axidraw can handle a pen weighing 1.5 ounces. I don't see the maximum weight in the Axidraw specs. Can you tell me if it can handle a pen weighing, say, 2 ounces?

dg1

With regard to your second paragraph advising how to move a stylus, I understand and appreciate that. That would be a bonus, the main goal is to get the keyboard working. Us evil mad scientists tend to do our best work after midnight but it's almost time for me to think about sleep. (I've actually got servos working pressing function keys on my keyboard, but they aren't as reliable as I would like. So Axidraw seems to be my off the shelf reliable solution.)

Windell Oskay

The recommended maximum weight of the pen is 45 g. 2 ounces ought to be fine, more than that if you can anchor the base.

dg1

Super, thanks. A novel use for your fascinating product.