Six years ago, I built a wifi-controlled pop bottle sailboat. Smartphone control wasn’t great, so I turned my decommissioned weather station into a remote control.

My re-used weather station project board is a homemade Arduino board, with an APC220 transceiver radio. I added two rotary potentiometers for rudder and sail control. I removed the Raspberry Pi in the boat, and connected another APC220 transceiver to the Arduino Uno that controlled the sail and rudder servos.

We drove to Downsview Park and launched the boat.

Control still wasn’t great:

• Controlling the sail and the rudder is fine, but with the boat just floating on the pop bottles, the rudder has very little effect. Our boat design itself needs improvement – I think this is currently the greatest issue.
• My transmitter and receiver code could use some optimization – as I was troubleshooting at home, my code limited updates, and was only sampling every second – controls seemed “laggy”.
• I’m using very inexpensive TowerPro MG995 servos, which many advise against using. They were fine for playing around with interfacing, but they are slow, they seem to have a hard time holding their position, as well as not consistently reaching their programmed position.

I did write my phone number on the boat in case the boat got stuck in the middle, and someone else eventually found it. In the end, it wasn’t required. We just played with the controls as the wind carried it to the other side – probably about 100 m.

Maybe some time over the next 6 years, I’ll optimize the RC code, install better servos, and improve the boat design by adding a keel.

Ever since I read about the ESP8266 in Make magazine in 2015, I’ve been wanting to build something with it. I picked up a Sparkfun ESP8266 Thing Dev board at Creatron, probably a year ago, and let it gather dust.

Enter 35 degree weather. I have a window air conditioner, that I install in a metal sleeve built into our wall. For some reason, the sleeve is sloped such that water flows INSIDE. When the A/C runs on humid days, the water it collects from dehumidifying can leak inside, creating an unpredictable annoying mess that has to be cleaned up.

I could pickup a commercial leak sensor, but that’s not fun, the mobile app is probably not very good, it probably sends more information than needed to its cloud service, will never receive updates, and it seems like we’re always reading about IoT device vulnerabilities.

So, I bought a water sensor ($2.20!) in June, connected it to the dev board, and started to write a client in the Arduino environment for the ESP8266, and the server in Node.js. Then summer happened. Today, it’s August, its only 24 degrees outside, the A/C is off, and I’m done! The client reads the sensor every 10 seconds, and calls the server with a standard web service call, which will check the sensor reading, and send an alert by email if a water leak is detected.

The code is simple, but I had challenges getting the ESP8266 to HTTP POST a JSON payload. It seemed every example I found used different libraries or versions than the ones I had installed. I eventually got it working.

In the end, we didn’t have any leaks this summer in any case, and I don’t expect to make use of this project. If you’re interested in checking it out, you can download the code here: https://www.hotelexistence.ca/projects/watersensor.zip

This website is running WordPress on an Amazon EC2 instance.

If I were looking to keep a blog, this is not how I would do things, I’d just use a service.  The micro EC2 instance is slow, I have ensure Linux is patched, WordPress is patched, etc…  But playing around with the server is as much fun as writing the blog.

Here are a few changes to the site recently:

• I run the EFF Privacy Badger on my browser at home, and I couldn’t believe how many trackers were running on my self hosted site, because I don’t track, and I don’t have ads.  I dropped the Youtube videos, that got rid of many (I just link to Youtube now instead of embedding).  I can’t remember what else I did, but now I’m just down to Google Fonts, used by the template.
• The site now defaults to HTTPS.  With default settings, Qualys rates the default Ubuntu 18.04 LTS Apache HTTPS setup on this site as an A.  Its funny how many important companies struggle to get this right on their sites, given how easy this is.
• Recently update the site to Ubuntu 18.04 LTS – the latest version of WordPress didn’t like the version of PHP on the previous LTS version I had been running (not sure what that was).  This is the third VM on which this site has been hosted.
• I hadn’t been resizing photos and the site got REALLY slow.  I’ve resized the largest ones – it’s not painfully slow anymore.  I may eventually move the image hosting to S3, but keep the server/DB on EC2 – I expect the site would run faster without increasing costs.

Update October 5th, 2019:

• Google Lighthouse ranks the site load speed at 100
• Finally got the fonts loading locally with the OMGF WordPress plugin. The site no longer has any external trackers!

I’m on a roll this week – a record number of posts (3 in 7 days…).

The bar code on my library card has been worn out for a while.  My last few trips, its probably taken about a minute for me to play around with the positioning of the card on the library’s scanner to get it to read correctly.

Years ago, I’d read how my friend Chris created a custom library card with all of his family’s card numbers on it.  Although I’m sure the instructions he provided would work (I suspect the library’s barcode readers handle many formats), the bar codes his method created didn’t match the one on the card.

Here’s how to get one that matches:

• The format is Codabar
• The Start and Stop character is ‘A’
• The Toronto Public Library’s account number already has a check digit, you don’t have to add one
• Many online generators exist.  I used abarcode.net

I printed mine and stuck it to my old card with packing tape.

My kids are both avid readers, but neither have been good with maintaining a reading log, sometimes requested by their teachers.

I thought if I reduced the effort required to maintain the reading log, they’d be more likely to track the books they read.  I created a website where, using a smart phone, they could just take a picture of the bar code on a given book.  The website would read the bar code, and make a call to the Google Books API to retrieve the book title and author, and add it to the reading log.

It was used for a month or two, and then the novelty wore off.  We’re back to just reading books, as opposed to tracking what we read, which I guess is the important thing anyway.

In the past, I’ve worked with AWS, but I thought I would use the Google Cloud platform for this project to try something different, and now my free trial has expired, so the site is no longer up.

I wanted to use the QuaggaJS in-browser (Javascript) bar code reader, which would save sending the bar code picture to the server, but, in testing, the Java based Zxing was much better at consistently reading the bar codes, so the website gets the user to take the picture of the bar code, sends the picture to the server, and the bar code is converted to an ISBN server-side.

I haven’t documented it, but source can be found here: https://github.com/raudette/readinglog

Willowdale is a game I made with my kids where you can explore our neighbourhood.  You can read more about how we created it in  Creating A Game.

The Game

You can access the game at
http://willowdale.s3-website-us-east-1.amazonaws.com/

Controls

• Arrow keys to navigate
• Enter key to advance dialog
• Move your character to the ladders to move from one map to the next

Hints and Things to See

We’re not gameplay experts – if you want to explore, disregard the following.  However, if you just want to see what we’ve implemented, you can check out the following:

• Walking into the kitchen at 55 Ellerslie will trigger dialog
• Walking into the patio stones in the middle room of 55 Ellerslie will take you to Candyland
• From Candyland, you can walk into Belle the fairy’s home.  Walking near Belle in her home will trigger dialog