Smart Poi

K8 One Button Remote with Arduino Nano

This is a post for K8 juggling equipment owners who are also into electronics. If you haven’t already read it, here is here is why I made my own K8 IR remote.

If you don’t do electronics, but own K8’s, try the animated demo! (instructions below).

K8 One Button Remote

The circuit is quite simple. A 9v battery powers the Nano via Vin pin. A transistor receives output from the Nano, and this triggers a large current in the 3 connected infrared LED’s. The reason for the transistor is to maximize the signal, output of Arduino is only 5v but we need more for better signal range. You may notice that there is no resistor on the LED’s. IR pulses are extremely short ON/OFF pulses and so are not likely to blow up the LED’s in this implementation. I did have one connected previously but the range suffered.

I made a fun web program to demonstrate the functionality, you can see it here:

K8RemoteDemo

The demo works best on PC but you can see it on a mobile.

How to use it: click on some of the remote buttons, then press the big grey square at the bottom right to start (scroll down/across if you can’t see it). Press the bottom right square again to cycle through the saved patterns.

Refresh the page if you want to try again. Some of the buttons are not implemented yet (eg. Demo)
My favorite is probably fade, followed by no. 5 which is my favorite K8 pattern anyway.

 

This transmitter (at least with the IR LED’s I have) is more powerful than the K8 remote I received from them.

The code I will post in another article, however it is really simple, while the button is being pressed, the saved signal is sent, once per second (not more – one of my K8 balls has stopped receiving I believe due to too many signals sent*)

Stop pressing the button and the remote is off (saving battery of course) and next time the signal will be a different one, depending on the program.

 

*I am not a K8 engineer but their equipment stores the last pattern in memory. I believe that a piece of EEProm memory is overwritten each time the signal is received, so take care to not send too many signals, or your equipment may stop working. On Arduino chips EEProm memory is rated for 100 000 rewrites, obviously this is a minimum but evidently I exceeded this in some experiments.

POV poi image to circle

What does this do? Visualize poi image as it is spinning around, software turns rectangular image into circular representation of poi image arc.

 

Select and upload your poi image (best results with 72px image) – only one at a time at the moment for testing. Currently only .jpg format supported.

wait for rotation

If page says “oops that page can’t be reached”, refresh after a couple of seconds – this is alpha version so not perfect.

Upload files

 

This program is optimized for visualizing SmartPoi (72px version) - the worlds first wireless streaming poi. See circusscientist.com for more details.

Lets stream some Pixels

First things first, have you tried setting up the breadboard test circuit?

Does the SmartPoiOffline sketch upload correctly, and display on 36 connected LED’s? (if you have a longer strip and don’t want to cut it, that’s fine, the rest will just be blank)

Ok it’s time to try streaming pixels.

First load the SmartPoiBasicStreaming sketch to your microcontroller. Right now this is only being tested on the D1 mini, but should work on any ESP8266 board.

The SmartPoiBasicStreaming_UDP_Send program works on PC or Android, you just need Processing IDE with Android Mode installed if you want to do Android.

First, switch on the D1 Mini with LED strip attached. Wait for the led’s to finish cycling their startup pattern, then you need to use the wifi settings to connect the device (PC, Android*) which is running the processing code to the Smart_Poi_2 access point. The password is for this test is: “bluefire”.

*Note: since Marshmallow version, Android has had a nasty “captive portal” detection which refuses to connect to AP’s unless they are able to access the internet. I understand why they did this (security), but without root the only workaround is to put the device in Airplane mode, then switch on WiFi while still in Airplane mode, and connect from there. The annoying notification should be ignored, as there is an option to “never connect to this network” in there somewhere and it will trip you up.  I should probably do a post about this. Just swipe it away, don’t click!!!

Once connected, start the program. Welcome to the world of streaming poi.

A couple of notes: the test program is not POV, it’s an animation (cylon effect) as this is easier to see on a breadboard. I have a complicated program to send images to the poi which are seen only when they are spun, however it’s easier right now to just start with a simple app for testing.

This program does demonstrate one advantage of streaming as opposed to rendering purely on the poi – that is control. It is trivial to change the colour from the random colours I have chosen to any you could wish. I had another version of this program with three knobs which can change the R, G, B values being sent. You could do a curve instead of straight lines, make the line fatter or thinner, slower, faster, and much more.

Have a go, and let me know what you think. Coming soon: more POV poi shenannigans!

 

 

 

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.

 

Android for Africa!

Living in Africa is absolutely analagous to living in the old wild west sometimes. Just driving to work here can be a life threatening proposition some days. Protests, cash-in-transit heists, blown up ATM’s, hijackings and street beggars at every traffic light all threaten to disturb ones peace at any moment.

A bit like running Android on your phone really. That is unless you are up to date with the latest patched version. Which runs on precisely two devices as far as I am aware. The rest of us are left to make shift in yesterday’s abandoned OS graveyard, where the bad guys have their playground.

Privacy concerns? First world problems! Just be thankful that nobody screen captured your banking app today – while slowly cooking your phone casing with illicit cpu bitcoin mining cycles.

From a development perspective the OS is no better, a dictatorship with a fickle overlord. Time to change your code again, unpack and repack the activity car, it’s an API roadblock. Pay the play store compliance tax now or try your luck on the sideloading second economy, where your cloned apps beg at the same alternative app store intersection as you, with a flashy ad platform sign held high.

Gotta love Android. It’s the wild west out here. Android for Africa!