hhmx.de

blinry

Föderation EN Di 01.08.2023 17:54:10

I've always wanted to build a compass belt, which indicates where north is using vibrations!

Today, I got the very first prototype working: A setup that vibrates when you point your smartphone north! 🧭

blinry

Föderation EN Di 01.08.2023 17:56:34

My thought was that smartphones already have good compass sensors, and can serve as a power supply – you just need to plug the belt into it!

But I might switch to a Bluetooth connection, an extra battery, and maybe a separate compass sensor in later iterations. It's just that simple sensors often seem to have a lot of drift…

blinry

Föderation EN Di 01.08.2023 18:13:15

I found a belt with a lot of holes a few weeks ago, and it seems like a good basis for the prototype!

So I designed clip-on holders for vibration motors (using <3), and I'm now printing a bunch of them! :)

I'm holding one of the clips, with a vibration motor already in it. It will clip on to the belt in the background, which has two lines of holes, surrounded by metal rivets.

CadQuery code for the clip. It looks very parametric.

A 3D model of the finished clip.

(Medien: 3)

blinry

Föderation EN Do 03.08.2023 12:00:48

Trying to get stripboard layouts as small as possible is quite fun, and could make a good puzzle game, I think!

Thinking of soldering this together later, if you have ideas how to make the footprint smaller, let me know! :D

A stripboard diagram of a Raspberry Pi Pico and two ULN2803A chips, connected together with some capacitors.

Schematic layout of this circuit.

(Medien: 2)

blinry

Föderation EN Do 03.08.2023 12:03:12

One problem I still have is that the wires of my vibration motors are *tiny*... They break off easily at both the soldering points, as well as the motor terminals. What's the usual way to mitigate this?

One wire of the vibration motor broke off from a bigger cable.

(Medien: 1)

blinry

Föderation EN Do 03.08.2023 17:06:18

It's done!! First time I've ever used a stripboard! Now assigning the pins in software and first testing! So exciting! 😆

A microcontroller, ICs and condensators soldered to a stripboard.

The back side. You see some stratches to interrupt the copper, and some mediocre solder points.

(Medien: 2)

blinry

Föderation EN Do 03.08.2023 17:10:22

Meanwhile, I'm printing an updated case for the vibration motors, which securely houses the fragile cables! Thanks to @psenough and @flauschzelle for the suggestion! :)

Black 3D-printed clips for motors. Thick blue wires come out of the casing.

(Medien: 1)

blinry

Föderation EN Do 03.08.2023 21:17:46

I assembled everything, and it works! <3 The vibration is very noticable through the belt!

It's controlled via a custom Android app, gonna tweak that tomorrow, and write documentation. :)

The belt is now covered with cables and motor clips.

The board I made is glued to one end with tape.

(Medien: 2)

blinry

Föderation EN Fr 04.08.2023 17:55:32

I built a haptic compass belt this week, that allows me to feel north using vibrations! 🧭

Here's how it works, and how you can build your own: blinry.org/compass-belt/

Me, a white, red-bearded person, points happily at the compass belt around my hips.

The compass belt is wrapped around my hips. It has a lot of blue cables, black plastic clips, and a brown circuit board.

(Medien: 2)