Category: Projects

Time for some Poi Sync

The esp8266 is an amazing chip. On my poi the Master* poi creates a wireless access point which the Slave* poi connects to – and Android app connects as well, in order to transmit images. No router needed, just switch on poi, 2nd poi connect automatically, connect phone and start sending pictures.

*I have designated these names, for descriptive purposes.

There are limits, however. The ESP chips have a limitation of 4 connected devices per access point device. If you want more devices talking to each other you need a Router to handle the traffic.

This is fairly simple using arduino examples but it brings up configuration issues. I wanted my poi to be able to be used in standalone as well as Master-Slave-Android configuration, and now Router-Multiple-Poi-Android as well. A few settings are in order.

The first option, standalone poi without wireless, I configured directly in the loop() of code. If no wifi signal has been received within the last 5 seconds the poi switch to backup images. Great, if my phone’s battery dies the show still goes on.

The second alternative (Router) is a bit harder to organize. First, there is a limitation where the chip has to be told if it’s in Access Point mode or not on boot. Ok so that’s a setting. Then we need to know what the static ip address is (hard coded but configurable via web interface) so that we don’t conflict with other poi. Also, once you are in Router mode, what if there is no router?

Right now, my poi check a web configurable EEProm switch on boot first, for Router mode on/off. If Router mode is on, the poi enter connect mode. If, after a certain amount of time, the router is not found, the poi restart in Access Point (master-slave-android) mode. However, upon rebooting again they revert back to Router check, so one has to manually set back to Access Point only mode if required.

I need a diagram here to really show what’s happening.

The problem came in if the router wasn’t configured correctly, or was simply not available, the poi needed a reliable way to get configured. My poi get configured by web interface (local network, no cloud) so AP mode was needed by default in case things went wrong.

Here is the note from my code:

//to activate in browser: http://192.168.1.78/router?router=1

//to deactivate: router=0

So I just type it in the browser on my connected Android or PC and the poi are set. I will assign this to a button on the app at some point.

Currently the only option for multi-poi is to send the same image to all poi simultaneously (only 3 pairs, that’s all I have). This looks great, but there is much more to do obviously. Just a matter of code

Time to go play a bit with the toys…

Simple D1 mini Circuit

Although the Smart Poi is based on ESP-01 for size reasons, I find it easier to use the excellent D1 mini for testing. Here is the basic setup:

Notice that the D1 mini is powered from a battery source (4 x NiMH AA in series). This is not entirely necessary, you could get away with plugging in the D1 mini via USB, and connecting the APA102 strip to the 5v pin. The problem comes in when the LED strip starts drawing too much power, you will have dropouts in Wifi connectivity, or wdt resets and won’t know if it’s the code or just power.

Use the offline code from my Github repo to get started:

SmartPoiOffline code

This code works fine on other Arduinos as well as ESP8266 chips. Just change the pins.

 

Smart Poi Emulators

Two emulators are featured here, the first takes all images in a folder and shows them in sequence, as they would look on the spinning poi:

 

The second program receives RGB values from serial connected poi chip and displays on screen. This is showing what is actually being sent out to the LED strip, useful for testing – I was getting a bit tired of spinning the poi whilst programming them and the Android transmitter app at the same time.

The image below is of the computer generated default offline patterns, but if wifi sent images are available it looks somewhat similar to the above. Colour is not yet optimized.

 

For the serial sending to work on the poi, a fairly large change in code is needed. The serial necessarily slows everything down drastically, so it’s for testing only.

What it’s really like to be a developer

The long road to Smart Poi, visualized:

In order to make this video I used a program called gource. It takes your Git commits and creates an infographic video automatically. I modified the programmer avatar using the –default-user-image setting.  If you want to see something spectacular, check out the linux kernel gource!

k8 Clubs what are they and don’t they come with a remote already?

K8 prophecy clubs and balls come with their own remote, which controls all the colour settings. Why did I make another remote then?

 

Well, first of all, the clubs and balls may glow in the dark, but the remote certainly doesn’t*. The remote is very small and conveniently fits in a pocket, however it is virtually impossible to determine by feel which end is the business end. And by that I mean the end with the IR LED on, so that your hasty button presses actually have an effect… because as we all know, if you point the remote at the stereo, the tv will not change channels.

*Update: I wrote to K8 recently with regards to getting some new equipment, and it turns out their new remotes glow in the dark. They also have an awesome new record pattern function, to make changing colours easier. Can’t wait until I can afford the new K8’s!

Then there are the fiddly buttons, I have to admit my eyesight is not the best and I have broken too many pairs of expensive prescription glasses to hazard wearing them at my juggling gigs (juggling club to the face… it happens). So inevitably I end up squinting in low light trying to see which button does what, I quickly decided this was not the way I wanted my show to go.

Here is a shorter (low ceiling) version of my show running from an IR dongle, on a laptop, synchronized with some DMX lights via midi. Super complicated setup, I gave up on this after a couple of years of doing it. I needed an easier way…

Introducing the ONE button remote.

How does this work? One very prominent button, when held down will repeatedly send the correct signal for my equipment at the time I am pressing it. Once pressed, the program increments to the next required signal and that one is sent on the next button press.

One button, many signals. So now, in my show I occasionally hold up a remote and change the program on my IR juggling toys. I don’t need to be able to see the remote in order to do this, finding the remote takes no time (it’s tied to my homemade juggling equipment stand) and the button is big and can be found in the dark. Also the signal of MY remote is quite a bit boosted from the k8 version.

Here is an arduino sketch which demonstrates the principle (without the IR, I will share the k8 codes if anyone is interested).

EepromOnOffLedExample

Simply put, there is a number saved in EEPROM. Every time the Arduino boots up, the number is incremented, and saved again in EEPROM. The saved number corresponds to an IR signal. Thus a different signal each time. I make sure to loop the number back to 0 again of course at some point, otherwise the EEPROM register will overflow, blowing up the Arduino in the process I imagine 😛

 

 

Smartpoi is open source

I am working towards opening up the whole thing, hopefully I can get some productive feedback this way. However, to make something for yourself is one thing, to share is another. Lets just say the code is not ready to be shared. #messyprogrammer a lot

In the meantime here is a simple POV example on github which will work for esp8266 connected to an APA102 144 strip (36 LED’s only for testing). Don’t forget to add a cap between +5v and GND.

SmartPoiOffline

Here is a test board I made up, you don’t need the whole lot, just one of the esp breakouts and the LED strip. Here I have 2 controllers (only one on at a time!) and also a voltage regulator, and accelerometer as well.

In case you are wondering, the Esp-01 is connected to the breadboard by this method: http://www.instructables.com/id/Making-ESP8266-01-module-breadboard-friendly/

Simply put, you remove the plastic pin spacers with plyers, and now the pins are bendable to a more breadboard friendly configuration. No soldering needed.