POV Fidget Spinner [160595]

This will be a Persistance Of Vision fidget spinner.

This one will not only be one of the popular fidget spinners. It will be a persistance of vision display. While spinning the toy, it will display Names, Messages or animation.
It will work from two CR2032 standard coin cells. It has a push-button to turn it on, change display modes and turn it off. To save batteries it also has a automatic power-off circuit.
Additionally a 3d-printed housing will be made.
This is a work-in-pogress. The picture shows the first prototype made of cardboard. It works, but it will be improved a lot.
The schematics file shows the second approach. I ordered a pcb of this version. It contains some changes to the prototype so development of the software will be made with this one.

More information and a more detailed description will follow...

Project Elements

Prototype (JPG, 1.09 MB)

This is the cardboard prototype

Prototype in action (JPG, 265.8 KB)

Cardboard Prototype in action

Real pcb (JPG, 177.57 KB)

The first real PCB. Ready to be populated :-)

Board Rear (JPG, 2.43 MB)

Rear of fully assembled board

Board Front (JPG, 2.73 MB)

Front of fully assembled board

Communicator (JPG, 885.96 KB)

USB communication interface

Housing outer (JPG, 1.18 MB)

Outer side of the 3d printed housing

Housing inner (JPG, 2.25 MB)

Inner side of the 3d printed housing

Mounted front (JPG, 848.76 KB)

Front of completely mounted spinner

Mounted back (JPG, 801.25 KB)

Back of completely mounted spinner

Complete device (JPG, 671.62 KB)

Completely mounted spinner

Spinning Spinner (JPG, 134.7 KB)

The new spinner in housing, spinning.

salvaging bearing (JPG, 916.31 KB)

How to salvage a ball-bearing from a cheap chinese spinner.

Communication (JPG, 1.54 MB)

Communication interface connected (USB-Serial-BOB)

Housing Cut-Out (JPG, 1.02 MB)

Housing with programmer/communication cut-out

Communicator connected (JPG, 1.36 MB)

https://youtu.be/P77r5pxlGOo

https://youtu.be/EHQTl0ZurMU

https://youtu.be/9R7IoDbTCgE

https://youtu.be/YKgrjJSl-Ms

Software Description (PNG, 85.54 KB)

Description of the Software

Mounting instructions (PNG, 89.17 KB)

Instructions how to mount the 3D housing together.

Hardware Description (PNG, 116.55 KB)

A description of the hardware

CLI description (PNG, 110.34 KB)

Description of the comand line interface.

Gerber Files (RAR)

Gerber files for PCB reproduction

3D Housing files (RAR)

3D files of the housing

Software (RAR)

Fidget-Spinner software with command line interface.

Bill of materials (PNG, 48.03 KB)

Schematics (PNG, 113.84 KB)

Current schematics of my fidget spinner

Updates from the author

Raabinator 7 years ago

Finally, a software version ist finished!
It contains user-configurable effects and texts.
There is also a description of the command line interface to customize the effects.
Also addad some new effects:

A battery gauge that shows battery level and voltage
A game mode that counts you rotations and remembers the last and maximum
Game-Result-Mode, shows the last and maximum rotation count
Scolling-Text, text is scrolled row by row from the left to the right
Word-Wise output is centered at the middle of the longest word

Additionally, i added a top part of the housing with a cut-out for a programming/communication header.

Uploaded some new videos to YouTube and linked them in.

A software description will follow in the next days...

0 Comment(s)

Raabinator 7 years ago

Uploaded some files:
- Gerber Data - to reproduce your owm PCB
- Bill Of Materials - the shopping list
- 3D Files - print out your own housing
- Mounting Instructions - how to build the housing together
- Hardware Description - description of the hardware and some design decisions

0 Comment(s)

Raabinator 7 years ago

The pcb is comletely populated.
Prototype of the housing is printed.
Device is completely mounted.
An improved version of the software is written.
Software now contains a font to display characters.
Display is double-buffered to do smooth animations without flicker.
Speed measurement and consistent output is implemented, so the picture is the same size independent of rotation speed.
Added some new pictures of pcb and housing.

More description will follow...

0 Comment(s)

Raabinator 7 years ago

The real pcb arrived. Now it's time to populate it.
Further software developmen will happen on this pcb.
The current software is quick-and-dirt. It was only to show the function of the prototype.
It is still a long way to the final features.

Currently included features:

Power on when holding the button down. There is a delay to avoid false power-on. While holding the button down the led-bar fills from the inner to the outer. When all leds are on the button can be released and the cpu latches the power supply.
Auto Power-Off. If neither the button is operated nor a movement is detected for 10 seconds the device switches power off. To show this, the leds extinguish from the outer to the inner. After that, the cpu releases the power-latch pin.
When not moving, the button acts as a kind of menu button. Each button press changes the option selection. The selected option is shown with the count of glowing leds. Options are not used yet.
PWM for the leds in still-mode. When not moving, the leds are super-bright. To avoid injury of the eyes and to save power, the leds are dimmed by a software-pwm.
Synchronisation with hall-sensor. The hall sensor is used to detect rotation and to determine position. When the hall-sensor passes the magnet, he led pattern is put out. Each millisecond the pattern is altered. With this approach the picture stretches, when the rotation speed decreases. Later, rotation speed will be measured by a timer. Altering of the pattern will also be controlled by a timer feed with a fraction of the measured rotation time. This will give a picture with equal size.

More to come...

Correction on project site: put Pictures and Schematic into the right place for download.

rjv 7 years ago

nice project: prototype 2 already looks good.
would love to have this in our elektor lab

1 Comment(s)

Discussion (2 comments)

rjv 7 years ago

we made one at the Elektorlab and it works fine. watch the video.

https://youtu.be/czltBvsBRtw

0 Comment(s)

Moonwalker 7 years ago

How is the balancing of the spinner since it uses batteries on 2 points only? From the video it looks it does not keep turining for much long?
Very interesting project btw!

rjv 6 years ago

hello dhelrod
In the Elektorlab we used an Anet A6 3D printer to print this housing.
especially for you, and other people who love to make their own stuff, we sell the anet a6
3d printer as a kit. please follow the link , to have a look at it:
https://www.elektor.com/anet-a6-homelab-3d-printer-kit

dhelrod 7 years ago

I wish there was a kit of parts (circuit board, case, etc.) that I could buy. Elektor labs has many good projects, and it is wonderful that schematics and code are provided, but kits are great for people who might not have a 3D printer or who don't want to order 5 custom circuit boards for US$100.

I would really like to build two for my kids.

Thanks for a great project!

Moonwalker 7 years ago

Yes its programmable too and with rechargeable battery. I bought one and it works very good. I just cant understand how they manage to build them so cheap.

rjv 7 years ago

our fidget spinner is programmable and versatile: the one on ebay is not!

Moonwalker 7 years ago

Ok thanks for explanation.
However the chinese were much faster in this project :)
http://www.ebay.com/itm/Intelligent-LED-Light-APP-Control-Hand-Spinner-Tri-Fidget-EDC-Toy-Focus-ADHD/292175346180?ssPageName=STRK%3AMEBIDX%3AIT&var=591112244714&_trksid=p2057872.m2749.l2649

Raabinator 7 years ago

On the 3rd arm, with the LEDs, there are two holes that can take M3 Screws. I added washers and nuts until balancing was ok.
It was hard to make a video with a smartphone. So i clamped the spinner in a parallel vice, pushed it and hoped to get a good shot. Then i cut the best part of it. Spin-time is much longer than shown. It depents a lot on the friction of the ball-bearing. It's not perfect, but fun ;-)