IoP – the internet of pets – predictive maintenance of a cat

Posted on by Daniel Kirstenpfad

In the interesting field of IoT a lot of buzz is made around the predictive maintenance use cases. What is predictive maintenance?

The main promise of predictive maintenance is to allow convenient scheduling of corrective maintenance, and to prevent unexpected equipment failures.

The key is “the right information in the right time”. By knowing which equipment needs maintenance, maintenance work can be better planned (spare parts, people, etc.) and what would have been “unplanned stops” are transformed to shorter and fewer “planned stops”, thus increasing plant availability. Other potential advantages include increased equipment lifetime, increased plant safety, fewer accidents with negative impact on environment, and optimized spare parts handling.

Wikipedia

So in simpler terms: If you can predict that something will break you can repair it before it breaks. This improvse reliability and save costs, even though you repaired something that did not yet need repairs. At least you would be able to reduce inconveniences by repairing/maintaining when it still is easy to be done rather than under stress.

You would probably agree with me that these are a very industry-specific use cases. It’s easy to understand when it is tied to an actual case that happened.

Let me tell you a case that happened here last week. It happened to Leela – a 10 year old white British short hair lady cat with gorgeous blue eyes:

Ever since her sister had developed a severe kidney issue we started to unobtrusively monitor their behavior and vital signs. Simple things like weight, food intake, water intake, movement, regularities (how often x/y/z).

I’ve built hardware to allow us to do that in the most simple and automated way. In the case of getting to know their weight we would simply put the kitty litter box on a heavily modified persons scale. I wrote about that already back int 2016.

When Leela now visits her litter box she is automatically weighed and it’s taken note that she actually used it.

A lot of data is aggregated on this and a lot of things are being done to that data to generate indications of issues and alerts.

This alerted us last weekend that there could be an issue with Leelas health as she was suddenly visiting the litter box a lot more often across the day.

We did not notice anything with Leela. She behaved as she would everyday, but the monitoring did detect something was not right.

What had happened?

The chart shows the hourly average and daily total visits to the litterbox.

On the morning of March 9th Leela already had been to the litter box above average. So much above average that it tripped the alerting system. You can see the faded read area in the top of the graph above showing the alert threshold. The red vertical line was drawn in by me because this was when we got alerted.

Now what? She behaved totally normal just that she went a lot more to the litter box. We where concerned as it matched her sisters behavior so we went through all the checklists with her on what the issue could be.

We monitored her closely and increased the water supplied as well as changed her food so she could fight a potential bladder infection (or worse).

By Monday she did still not behave different to a degree that anyone would have been suspicious. Nevertheless my wife took her to the vet. And of course a bladder infection was diagnosed after all tests run.

She got antibiotics and around Wednesday (13th March) she actually started to behave much like a sick cat would. By then she already was on day 3 of antibiotics and after just one day of presumable pain she was back to fully normal.

Interestingly all of this can be followed up with the monitoring. Even that she must have felt worse on the 13th.

With everything back to normal now it seems that this monitoring has really lead us to a case of “predictive cat maintenance”. We hopefully could prevent a lot of pain with acting quick. Which only was possible through the monitoring in place.

Monitoring pets is seemingly becoming a thing – which lead to my rather funky post title declaration of the “Internet of Pets”. I know about a certain Volker Weber who even wrote in the current c’t magazine about him monitoring his dogs location.

Health is a huge topic for the future of devices and gadgets. Everyone will casually start to have more and more devices in their daily lifes. Unfortunately most of those won’t be under your own control if you do not insist on being in control.

You do not have to build stuff yourself like I did. You only need to make the right purchase decisions according to things important to you. And one of these things on that checklist should be: “am I in full control of the data flow and data storage”.

If you are not. Do not buy!

By coincidence the idea of having the owner of the data in full control of the data itself is central to my current job at MindSphere. With all the buzz and whistles around the Industry IoT platform it all breaks down to keep the actual owner of the data in control and in charge. A story for another post!

can your kitchen scale do this trick? – ESP8266+Load Cell+MQTT

Posted on by Daniel Kirstenpfad

Ever since we had changed our daily diet we started to weigh everything we eat or cook. Like everything.

Quickly we found that those kitchen scale you can cheaply buy are either not offering the convenience we are looking for or regularly running out of power and need battery replacements.

As we already have all sorts of home automation in place anyway the idea was born to integrate en ESP8266 into two of those cheap scales and – while ripping out most of their electronics – base the new scale functionality on the load cells already in the cheap scale.

So one afternoon in January 2018 I sat down and put all the parts together:

ESP8266 + HX711 + 4 Load Cells
my notes of the wiring… this might be different for your load cells…

After the hardware portion I sat down and programmed the firmware of the ESP8266. The simple idea: It should connect to wifi and to the house MQTT broker.

It would then send it’s measures into a /raw topic as well as receive commands (tare, calibration) over a /cmd topic.

Now the next step was to get the display of the measured weights sorted. The idea for this: write a web application that would connect to the MQTT brokers websocket and receive the stream of measurements. It would then add some additional logic like a “tare” button in the web interface as well as a list of recent measurements that can be stored for later use.

the web app. I am not a web designer – help me if you can! ;-)

An additional automation would be that if the tare button is pressed and the weight is bigger than 10g the weight would automatically be added to the measurements list in the web app – no matter which of the tare buttons where used. The tare button in the web app or the physical button on the actual scale. Very practical!

Here’s a short demo of the logic, the scale and the web app in a video:

You can grab the sourcecode for the Arduino ESP8266 firmware as well as the source code for the web application here.

Apple Airplay for SONOS (in Docker)

Posted on by Daniel Kirstenpfad

We’ve got a couple of SONOS based multi-room-audio zones in our house and with the newest generation of SONOS speakers you can get Apple Airplay. Fancy!

But the older hardware does not support Apple Airplay due to it’s limiting hardware. This is too bad.

So once again Docker and OpenSource + Reverse-Engineering come to the rescue.

AirConnect is a small but fancy tool that bridges SONOS and Chromecast to Airplay effortlessly. Just start and be done.

It works a treat and all of a sudden all those SONOS zones become Airplay devices.

There is also a nice dockerized version that I am using.

Converting ひらがな to “hiragana” and カタカナ to “katakana” – Romaji command line tool

Posted on by Daniel Kirstenpfad

I had this strange problem that my car was not able to display japanese characters when confronted with them. Oh the marvels of inserting a USB stick into a car from 2009.

stupid BMW media player without proper font

Now there’s no real option I know of without risking to brick the car / entertainment system of the car to get it to display the characters right.

Needless so say that my wifes car does the trick easily – of course it’s an asian car!

Anyway. I wrote a command line tool using some awesome pre-made libraries to convert Hiragana-Katakana characters to their romaji counterpart. 

You can find it on github: https://github.com/bietiekay/romaji 

Join me implementing a neural network to improve accuracy of an OpenSource indoor location tracking system

Posted on by Daniel Kirstenpfad

To all techies reading this:

GIST: I am looking for interested hackers who want to help me implement a neural network that improves the accuracy of bluetooth low energy based indoor location tracking.

Longer version:

I am currently applying the last finishing touched to a house wide bluetooth low energy based location tracking system. (All of which will be opensourced)

The system consists of 10+ ESP-32 Arduino compatible WiFi/Bluetooth system-on-a-chip. At least one per room of a house.

These modules are very low powered and have one task: They scan for BLE advertisements and send the mac and manufacturer data + the RSSI (signal strength) over WiFi into specific MQTT topics.

There is currently a server component that takes this data and calculates a probable location of a seen bluetooth low energy device (like the apple watch I am wearing…). It currently is using a calibration phase to level in on a minimum accuracy. And then simple calculation matrices to identify the most probable location.

This all is very nice but since I got interested in neural networks and KI development – and I think many others might as well – I am asking here for also interested parties to join the effort.

I do have an existing set-up as well as gigabytes of log data.

I know about previous works like „Indoor location tracking system using neural network based on bluetooth“

Now I am totally new to the overal concepts and tooling and I start playing with TensorFlow right now.

If you want to join, let me know by commenting!

Source: http://ieeexplore.ieee.org/document/7754772/

making your home smarter use case #14 – prevent fires while charging LiPo batteries

Posted on by Daniel Kirstenpfad

Did you know how dangerous Lithium-Polymer batteries can be? Well, if not treated well they literally burst in flames spontaneously.

So it’s quite important to follow a couple of guidelines to not burn down the house.

Since I am just about to start getting into the hobby of FPV quadcopter racing I’ve tried follow those guidelines and found that the smart house can help me tracking things.

Unfortunately there are not a lot of LiPo chargers available at reasonable price with computer interfaces to be monitored while charging/discharging the batteries. But there are a couple of workarounds I’ve found useful.

  1. a proper case. I’ve got myself one of those “Bat-Safe” boxes that fit a couple of battery packs and help me store them safely. Even if one or many burst into flames the case is going to contain any heat and fire as good as possible and with the air / pressure filter it’ll hopefully get rid of most of the very nasty smoke (I hear). Cables go into it, so the actual charging process takes place with everything closed and latched.
  2. the obvious smoke detector which is on it’s own connected to the overall fire alarm is mounted on top, like literally on top. It’ll send out the alert to all other smoke alarms in the house making them go beep as well as sending out high priority push notifications to everyone.
  3. an actual camera is monitoring the box all the time calling on alerts if something is fishy (like making sound, smoke, movement of any sort). When charging is done the charger will beep – this is being caught by the cameras microphones and alerts are sent out.
  4. the temperature inside the case is monitored all the time. The surrounding temperatures are usually pretty stable as this case is stored in my basement and as the charging goes on the temperatures inside the case will climb up and eventually level out and fall when charging / discharging is done. Now the system basically will look at the temperatures, decide wether it’s rising of falling and alerting appropriately.

There’s a couple more things to it, like keeping track of charging processes in a calendar as you can see in the flowchart behind all the above.

making your home smarter use case #13 – correlations happen

Posted on by Daniel Kirstenpfad

There are a lot of things that happen in the smart house that are connected somehow.

And the smart house knows about those events happening and might suggest, or even act upon the knowledge of them.

A simple example:

In our living room we’ve got a nice big aquarium which, depending on the time of the day and season, it is simulating it’s very own little dusk-till-dawn lightshow for the pleasure of the inhabitants.
Additionally the waterquality is improved by an air-pump generating nice bubbles and enriching the water with oxygen. But that comes a cost: When you are in the room those bubbles and the hissing sound of the inverter for the “sun” produces sounds that are distracting and disturbing to the otherwise quiet room.

Now the smart home comes to the rescue:

It detects that whenever someone is entering the room and staying for longer, or powering up the TV or listening to music. Also it will log that regularly when these things happen also the aquarium air and maybe lights are turned off. Moreso they are turned back on again when the person leaves.

These correlations are what the smart house is using to identify groups of switches, events and actions that are somehow tied together. It’ll prepare a report and will recommend actions which at the push of a button can become a routine task always being executed when certain characteristics are lining up.

And since the smart house is a machine, it can look for correlations in a lot more dimensions a human could: Date, Time, Location, Duration, Sensor and Actor values (power up TV, Temperature in room < 22, Calendar = November, Windows closed => turn on the heating).

“making your home smarter” – use case #12 – How much time do I have until…?

Posted on by Daniel Kirstenpfad

Did you notice that most calendars and timers are missing an important feature. Some information that I personally find most interesting to have readily available.

It’s the information about how much time is left until the next appointment is coming up. Even smartwatches, which should should be jack-of-all-trades in regards of time and schedule, do not display the “time until the next event”.

Now I came across this shortcoming when I started to look for this information. No digital assistant can tell me right away how much time until a certain event is left.

But the connected house also is based upon open technologies, so one can add these kind of features easily ourselves. My major use cases for this are (a) focussed work, plan quick work-out breaks and of course making sure there’s enough time left to actually get enough sleep.

As you can see in the picture attached my watch will always show me the hours (or minutes) left until the next event. I use separate calendars for separate displays – so there’s actually one for when I plan to get up and do work-outs.

Having the hours left until something is supposed to happen at a glance – and of course being able to verbally ask through chat or voice in any room of the house how long until the next appointment gives peace of mind :-).

 

“making your home smarter”, use case #11 – money money money

Posted on by Daniel Kirstenpfad

The Internet of Things might as well become your Internet of Money. Some feel the future to be with blockchain related things like BitCoin or Ethereum and they might be right. So long there’s also this huge field of personal finances that impacts our lives allday everyday.

And if you get to think about it money has a lot of touch points throughout all situations of our lifes and so it also impacts the smart home.

Lots of sources of information can be accessed today and can help to stay on top of the things going on as well as make concious decisions and plans for the future. To a large extend the information is even available in realtime.

– cost tracking and reporting
– alerting and goal setting
– consumption and resource management
– like fuel oil (get alerted on price changes, …)
– stock monitoring alerting
– and more advanced even automated trading
– bank account monitoring, in- and outbound transactions
– expectations and planning
– budgetting

After all this is about getting away from lock-in applications and freeing your personal financial data and have a all-over dashboard of transactions, plans and status.

“making your home smarter”, use case #10 – Fire and Water alarm system

Posted on by Daniel Kirstenpfad

Water! Fire! Whenever one of those are released uncontrolled inside the house it might mean danger to life and health.

Having a couple of fish and turtle tanks spread out in the house and in addition a server rack in the basement it’s important to know when there’s a leak of water at moments notice.

As the server-room also is housing some water pumps for a well you got all sorts of dangers mixed in one location: Water and Fire hazard.

To detect water leaks all tanks and the pumps for the well are equipped with water sensors which send out an alerting signal as soon as water is detected. This signal is picked up and pushed to MQTT topics and from there centrally consumed and reacted upon.

Of course the server rack is above the water level so at least there is time to send out alerts while even power is out for the rest of the house (all necessary network and uplink equipment on it’s own batteries).

For alerting when there is smoke or a fire, the same logic applies. But for this some loud-as-hell smoke detectors are used. The smoke detectors interconnect with each other and make up a mesh for alerting. If one goes off. All go off. One of them I’ve connected to it’s very own ESP8266 which sends a detected signal to another MQTT topic effectively alerting for the event of a fire.

In one of the pictures you can see what happened when the basement water detector did detect water while the pump was replaced.