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I'm wondering how to build a module just like the ones that are in kids shoes that light up. I've taken a few of these out and would like to make my own circuit but I'm not sure if it is possible. I've made blinking LED circuits before but they had an on/off switch. I like how the sensor turns it on and does the flashing cycle then turns itself off.

I'd like to make the battery replaceable and change the pattern of the LED blinks. My plan was to embed it into my kids bike and other things.

My guess is that a special machine or tool is needed to embed the cycle onto the circuit but I hope there is a different method to achieve the same result without using a power hungry microprocessor.

I've checked youtube but I haven't found anything similar to this.

If anyone can steer me in the right direction that'd be awesome.

I found the modules for sale here, 2018 popular shoe decorations vibration sensor flashing led shoe sole lights

Vibration/Shake Sensor from ebay, 10PCS Vibration Switch Shake Sensor Switch for Skates Gyro output Shake Rod 9P9

Module with LED

Module showing battery and sensor

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  • \$\begingroup\$ A uC can draw far less than the LED on 32kHz \$\endgroup\$ – Sunnyskyguy EE75 Sep 22 '18 at 18:58
  • \$\begingroup\$ That module is a nice find. You can avoid a lot of program and development by using that, or you can use my answer to build one from scratch. \$\endgroup\$ – Passerby Sep 22 '18 at 19:01
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    \$\begingroup\$ Tony is right to point out that MCUs can easily achieve this better than can any discrete analog circuit made from standard parts (a custom ASIC, of course, would be optimal but the NRE would put it out of reach.) I'd recommend the TI MSP430 which can idle around on its VLO with only a few microamps, while at the same time detecting a spring/contact arrangement to start the blinking from vibration. You could even shut down the VLO itself and just wake up on a pin change, I suppose. Still less current. Yes, you'd need specialized tools and some assembly code. \$\endgroup\$ – jonk Sep 22 '18 at 19:45
  • \$\begingroup\$ By specialized tools, you mean a msp430 launchpad, which has all you need to get started for the price of a coffee. And can be done in c or c++ instead of assembly. Or use energia, the arduino framework for msp430. \$\endgroup\$ – Passerby Sep 23 '18 at 1:24
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You can make fun lights with a few different ways.

One, is a 555 timer or timers, and a few switches to change the flashing mode or times. Very analog method. It will stop once the trigger stops. As you see, a vibration sensor is used. A simple vibration sensor is a spring coil, around a stiff wire. Or a ball or mercury tilt sensor.

The other is a microcontroller. You can program it to vary colors how ever you want it to, speed, pattern, etc. You would have to do it from scratch or by copying someone's project. A basic arduino like project. Tons of them on google or instructables.com. it will listen for an input like the tilt sensor to turn it in and will turn off after it sees no input after x seconds or whatever you program.

The other, is dedicated fun light ICs. TI makes one. It takes digital instructions to affect the color and flashing of the leds. I'll link it later. But you would still need a microcontroller. This allows you to do less programming, as the IC handles fading and other math for you.

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  • \$\begingroup\$ Excellent suggestion, I happened to have a 555 timer from an arduino kit and was able to get a great blink rate going. Would there be a way for the trigger to open a window of time that the 555 timer would stay on instead of it turning off when the trigger stops? Maybe something in the middle of the trigger and the 555 timer or something to that effect. The module I'm trying to mimic stays active for about a second. I know the arduino can do this for sure but I'm trying to keep battery consumption as low as I can. \$\endgroup\$ – Tommy Solomon Sep 22 '18 at 23:48
  • \$\begingroup\$ @Tommy you would need another 555, or the 556 dual (literally 2 555 in one package)timer. Use one in the one shot mode, and that triggers the other. Or add an Resistor Capacitor delay circuit to the trigger. \$\endgroup\$ – Passerby Sep 23 '18 at 1:21
  • \$\begingroup\$ Ok, I've made two separate 555 circuits each with 5v (mono-stable for the one shot mode and the other is astable). How do I trigger the astable circuit with the one shot circuit? The output is too weak to power the astable circuit. My guess is they will both use the same positive of one power source but I'm not sure or I'm off completely. \$\endgroup\$ – Tommy Solomon Sep 28 '18 at 1:40
  • \$\begingroup\$ You can control a 555 by three pins. Trigger, reset, and control. You wouldn't use it to control the power pin. It varies, and it's be years since I've used one. See elo.jmc.utfsm.cl/sriquelme/apuntes/555/el%2520timer%2520555.pdf for some examples of a one shot controlling an astable. And Google 556 circuits for examples. \$\endgroup\$ – Passerby Sep 28 '18 at 3:31
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Here is the completed solution:

The monostable 555 timer is triggered by the vibration sensor. The output of the monostable timer is connected to the transistor base with a 100k resistor. The transistor closes the circuit (negative side) for the astable 555 timer and the decade timer. The astable timer runs the pulse for the decade timer then when the duration is over it shuts off. The Potentiometers control how long the duration (Monostable Timer) and pulse (Decade Timer) will be.

This was the second completed circuit. The first one didn't work properly so I don't think I soldered it correctly and started from scratch. I mounted this to a small scooter but once weight was put on the scooter it didn't work properly.

I also made a Arduino nano version using the vibration sensor to trigger 17 LEDs. Once the sensor was triggered it ran a knight rider LED sequence which worked great but doesn't seem to be battery friendly. Currently I'm trying to figure out how to integrate a sleep and trigger to help with battery consumption.

I'm still quite new to all this and it really tested my soldering skills. I tried to have the monostable timer directly trigger the astable timer but one LED always stayed on and I didn't know how to have the decade timer turn off. I was thinking that I might have to put the whole circuit in epoxy in order for it to work when pressure is applied to it or not use ic sockets. I do like how it came out but I'd like to make this much better.

ICs

Circuit

Breadboard

Items used: 1 SW-18015P Electronic Vibration Sensor, 2 LCM 555 Timers, 1 2n2222 Transistor, 1 CD 4017 Decade Timer, 2 Capacitors (Electrolytic) 470uf 16v & 1uf 50v, 10 LEDs, 2 Variable Potentiometers (10k), 4 Resistors (220R,1k,10k,100k).

Nano Version: Nano with trigger

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