• Trill

  • Trill Craft Multiple Pads Being Triggered

Hi all,

I have a Bela board attached to a Trill Craft, which has six lines of conductive thread sewn into a shirt, see below.
Each line is connected to a pad, and I'm trying to play different sounds depending on which line is touched.

I have print statements indicating which line is touched. However, I'm encountering an issue where only line 1 consistently plays a sound when touched. Some of the other lines do not register the touch at all, while others trigger sounds from line 1 or neighboring lines. I have wrapped inductive casing around each thread to try to prevent cross-capacitance, pictured below.

I suspect capacitance is jumping across the threads, though that doesn't explain why some lines aren't working. Each line is not touching another, and I have checked all the connections. Adjusting the prescalers and thresholds hasn't solved the problem; it causes some lines to trigger too close together and others not at all. I'd need a way to adjust each touch pad individually, as they are all behaving differently, but I haven't figured out if that's possible.

Has anyone faced similar issues, and how did you resolve them?

Thank you!

Open the Trill/craft-visual example and run it, then open the Bela GUI. Set the mode to RAW and ensure that all connected pads are not saturated. If they are, increase the prescaler value and make a note of the value you use. Then in your project, after calling setup() on the trill object, add

usleep(10000);
trill.setPrescaler(x);
usleep(10000);
trill.updateBaseline();

where x is the prescaler value you figured out with the example.