Chris on weeknotes this week, largely working on applications for My Baby’s Got LED. Which feels like a reasonable opportunity to mention we’ve just added MBGL kits to our store. So you can buy everything you need in one place to recreate these projects at home*.

*(Liverbird not included)

Apart from work for a client the two projects I’ve mostly spent time on this week have both used MBGL. One an interactive sign for a Bar/radio station and the other testing WLED mapping to give an new look to the DoES Liverpool coffee monitoring liverbird.

Melodic Distraction is a radio station and bar based in the fabric district. They were looking to improve the look of their street sign, and bought a My Baby’s Got LED kit to liven it up. They removed the old strip lighting and connections and replaced it with a strip of RGB Leds around the circumference. To prevent noise on the data line, we used twin core cable for the power and a seperate shielded line for the data to the lights. Now it’s up and running, the next job is to link it their music output.

In DoES Liverpool, the coffee machine is hooked up to a SONOFF, which publishes an MQTT message whenever a fresh brew is started. Also connected to the DoES network is a large liverbird sign, formerly on the side of the Liverpool Echo building. It’s now full of LEDs controlled by a MY Baby’s Got LED board. Usually, the liverbird flashes a different colour when the coffee is ready, I wanted to see if we could use the lights like a progress bar, to show how long it would be before the coffee was brewed.

By default, WLED expects the addressable lights to be sequential, starting at address zero and working up. In the liverbird the lights are threaded around the frame, up one leg and down the other. As a result the order of their physical addresses doesn’t fit a neat pattern of rows. Luckily, WLED has a mapping trick to get round this. It’s possible to add a JSON-formatted map which lists the physical address of each led in the order you’d actually like them to be used.

With this setup we can use Node-RED to trigger an event when the SONOFF publishes a message to let us know the brew has started. In this flow we can also calculate the time elapsed from when this notification is received. We happen to know that it takes 270 seconds for a pot of coffee to brew, so we can calculate the percentage of brew time elapsed. With the leds in a sensible order it is really easy in WLED to display this using the ‘Percent’ effect, with the percentage we want to visualise as the ‘Intensity’ value.

      "col": [[255, 0, 0],[0, 0, 0]]

This example JSON sets the effect to ‘Percent’ (fx:98) and uses the payload value to set the intensity (ix:).

Nikki’s week consisted of filming the liverbird filling up with the coffee pot and editing the video to make it social media friendly, which took more steps than she’d like to admit and had some minor technical difficulties in the form of a dodgy cable when trying to get the laptop to read the camera. But despite that, it’s now up on Twitter!

She’s also been looking at canvas models for the Ackers Bell and trying to make some headway with that, though progress is slow. The big thing was sorting out the pricing for the My Baby’s Got LED starter kits, and finally getting those on Tindie ready to be sold!

And finally, Adrian is continuing with some really exciting client work, but nothing that can be discussed here yet. You’ll have to trust us for now, and find out more as soon as we can share!