Mike O’Connor
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mikeoconnor.bsky.social
Mike O’Connor
@mikeoconnor.bsky.social
570 followers 440 following 1.1K posts
By day - Machine Learning.

By night - Amateur photographer, tinkerer, drinker of IPA

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mikeoconnor.bsky.social
London with a baby is a different experience altogether.
A baby sitting in a pram at a crosswalk, as viewed from above and behind. The top of his head, and his little feet are visible. The crosswalk is in the UK, and has “<- look left” written on the street so that pedestrians know where the traffic comes from.
October 18, 2025 at 9:20 AM
mikeoconnor.bsky.social
Installed the unit in my utility closet this week. Two temperature probes for each loop - one for hot and one for cold. The flow gauges tell me how much water is circulating, so I can estimate the watts of thermal energy sinking into the floors in real time. Kind of amazed that it works so well.
Photo of the distribution block for my floor heating system which sends hot water to different parts of the house. The hot side is above, with labels corresponding to each of the rooms served by this circuit. There are thermistor probes zip-tied to the hoses. I later insulated them so that they more accurately measure the inlet and outlet temperature of each loop. The flow gauges on top of the hot water manifold indicate the volume per minute of water moving through the system. Water is precisely 1kg per liter, which makes it very easy to estimate the mass flow rate of the system. All I need to compute the heat dissipation is the specific heat of water, which is easy to obtain.
October 17, 2025 at 7:20 PM
mikeoconnor.bsky.social
Finally mustered up the courage to design a custom PCB in @kicad.org and send it off for manufacture. Only one bodge wire required, to deal with an island in my 3.3v plane. Very pleased with myself. This is a 16 channel temperature probe that I'll be using to monitor each loop in my floor heating.
Bare black PCB in my hand, with component footprints visible in the silkscreen. The board is titled "Raspberry Pi Pico W Thermocouple Multiplexer" The PCB with a handful of components placed on top of it, including the pico board and the two ADC chips with their corresponding screw terminals. View of the board in its enclosure from an off-axis, where the holes in the side of the enclosure are visible. The USB port on the long side of the enclosure allows the Pico to be plugged into power. Top down angle of the assembled board placed inside of a 3D printed enclosure. There are NTC thermistor leads strung through the side of the enclosure and connected to each of the 16 terminal blocks.
October 15, 2025 at 6:50 PM
mikeoconnor.bsky.social
I love it when a plan comes together
Time series chart of the freezer ambient temp as well as the water temperature. The water remained at the same temp from 9:30 until about 1:15, and has finally started getting colder again.
August 3, 2025 at 11:32 PM
mikeoconnor.bsky.social
Today I used the latent heat of water to precisely calibrate some thermometers I'm using to measure the temperature of the smoker in my garden. Water freezes at 0°C, but before it does, it sits at 0 for a while before crystalizing and continuing to cool off.
Screenshot of the temperature history of 2 thermometers. One in yellow is taken from an ambient air temperature sensor inside my freezer. It reads about -10 degrees, and the cyclical pattern of the compressor is visible in the trace of the temperature line. The other, in blue, is the temperature I'm measuring with a probe in an ice cube tray. The temperature dropped steadily until it hit the freezing point of water. It has since plateaued at that temperature while the latent heat of the liquid water is abosorbed by the freezer. Eventually, when it crystalizes, the temperature will continue to drop. but until then, this horizontal line serves as an excellent reference point for 0°C.
August 3, 2025 at 9:17 PM
mikeoconnor.bsky.social
My first car was my mom's hand-me-down Previa. It was powder blue, had all wheel drive with a manual transmission, and by the end of its life it had flames and a racing stripe painted on it. I loved it so much. One day, we'll be reunited.
A photo of the front of my van. Its racing stripe runs from the front to the back.
July 30, 2025 at 9:23 AM
mikeoconnor.bsky.social
First batch of blackberries came off the vines this weekend. So I made jam:
450 grams of blackberries in a bowl on my kitchen scale. Blackberries cooking in a pot on my stove, to become jam. The finished jam in a jar in my hand Jam on sourdough toast with butter underneath. Delicious
July 29, 2025 at 9:32 AM
mikeoconnor.bsky.social
It's official, I've joined the dark side. Can't wait to inundate you all with my AI and Machine Learning hot-takes.
Screenshot of my LinkedIn header, with my new title as Machine Learning Engineer
July 23, 2025 at 1:42 PM
mikeoconnor.bsky.social
More #plotterart on the home-built #penplotter
July 3, 2025 at 6:39 PM
mikeoconnor.bsky.social
Also, shoutout to @openstreetmap.bsky.social, @qgis.fosstodon.org.ap.brid.gy and the Dutch government for the commitment to easily accessible geospatial #opendata. All of this was obtained and plotted using free online tools and software which makes me really happy.
A pen-plotter drawing of the city of Haarlem in The Netherlands. It's drawn on blue paper, reminiscent of a blueprint. The ink used for the bodies of water was gold metallic, highlighting the Spaarne river running up the right side of the image in a lazy winding pattern. The north embankment of the city forms triangular points, indicative of the city's old fortifications from centuries past. The handful of canals in Haarlem are also gold, and frame the outline of the old city in bright color against the blue background. The city itself is drawn with a mixture of white and black pens. The white outlines of every building in the city create a mixture of geometric and organic patterns, depending on the age of the neighborhoods being mapped. Black roads and bike paths are dark against the deep blue paper, only barely visible in comparison to the white house outlines. The rail line that passes through the north side of the old city cuts across horizontally, and is drawn in silver. The paper this was drawn on is 50x70cm and there is a visible margin around the outside where the pen plotter stopped drawing its lines. I'm really proud of this piece of art.
June 26, 2025 at 9:15 PM
mikeoconnor.bsky.social
#Plotter project number two:
June 26, 2025 at 8:24 PM
mikeoconnor.bsky.social
I streamlined the toolpath algorithm and it cut the print time down by 75%.
June 22, 2025 at 6:42 PM
mikeoconnor.bsky.social
I find this endlessly fascinating and it makes me want to write my own tool path algorithm. #plotter #plotterart
June 21, 2025 at 10:36 PM
mikeoconnor.bsky.social
Chuffed
June 20, 2025 at 10:17 PM
mikeoconnor.bsky.social
My wife, for Father’s Day, commissioned an illustrator to produce vector graphics of me and my son. I love them so much, and they provided the perfect image for me to plot on my new scratch-built pen plotter.
Black construction paper on a white table. The construction paper has a line drawing of a father and son. Their foreheads are touching, father‘s eyes closed. The pen is silver, and stands out strongly against the black paper background. The robot used to print the images visible in the margins of the photograph.
June 20, 2025 at 9:29 PM
mikeoconnor.bsky.social
Big things are happening
June 14, 2025 at 7:24 PM
mikeoconnor.bsky.social
Progress
June 12, 2025 at 10:25 AM
mikeoconnor.bsky.social
I told my dad to bring Reese‘s pieces when he came to visit this week. He asked me how many I wanted him to bring. My answer was to ask him how much he thought was a ridiculous amount, and to double that. He did not disappoint.
A photograph of three tubs of Reese’s pieces stacked on top of each other. Each tub is 1.75 kg. There’s an empty wine bottle standing next to them for scale. The wine bottle is dwarfed by the tower of Reese’s pieces.
June 9, 2025 at 7:28 PM
mikeoconnor.bsky.social
Echoes of ZIRP are still reverberating out there.
Picture of a washing machine, with the option to preorder it. The ad copy says the following: "Bespoke AI Washing Machine Enjoy a smart way to wash with AI Home, an intuitive control center. Personalise your washing by remembering your habits, plus, after the washing is done, it provides a laundry report."
June 3, 2025 at 10:29 AM
mikeoconnor.bsky.social
Splurged on a laser scanner and it did not disappoint.
May 29, 2025 at 4:46 PM
mikeoconnor.bsky.social
Hard to overstate how useful the 3d printer has been for projects like this.

#3dprinting
Linear rod and bearing for the gantry Various prototypes on my desk Two versions of the gantry bracket in my hand The loose pieces before assembly
May 23, 2025 at 8:45 PM
mikeoconnor.bsky.social
Scratch build A1 plotter design is slowly coming together…
May 23, 2025 at 8:42 PM
mikeoconnor.bsky.social
Been experimenting with glass-fiber ABS on the printer and I’m really happy with the results. Dimensionally stable, less warping, really rigid, and way cheaper than the carbon alternatives.

#3dprinting
Two bracket prototypes, one in white and one in gray ABS-GF.
May 22, 2025 at 11:08 PM
mikeoconnor.bsky.social
Gentle reminder not to forget about the pocket doors when drilling a hole through the wall.
May 11, 2025 at 8:05 PM
mikeoconnor.bsky.social
Did a large-format portraiture workshop today. Such a cool experience.

#photography
May 10, 2025 at 9:00 PM