A calculator Android app I’m writing needed an expression parser, so I researched how to build one. I started by reading a bit of Google’s Android Open Source Project Calculator source to get some ideas.
Ribbon Cutting
We’re celebrating Blue Paper Technology’s Site Founding Day today, the day after Oregon’s birthday. Welcome!
Chinchilla Cam: Installing the Raspberry Pi Camera Module and OpenCV
For some time we’ve caught rare glimpses of small, rabbit-like animals who seem to be living under our front porch. We’ve seen little, round ears bobbing past the window, footprints in the snow, and during one hot summer I found a dead chinchilla in the garage – the poor thing couldn’t take the heat.
So I’ve decided to capture photos of the little fellows – or at least try – using a Raspberry Pi, motion-detecting Webcam. The project as it unfolds is stored on my ChinchillaCam Repository on github.
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Does Superglue work with 3D Prints?
Having read Clifford Smyth’s excellent book, Functional Design for 3D Printing, I was anxious to try out his method of cutting a design into parts and gluing those parts together after printing.
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Travel is Broadening, 1873
In going through old family papers, I happened on a letter from my great-grandfather, John Foshay, to his wife, my great-grandmother, Martha (Whealdon) Foshay. It’s a letter composed mid-trip on a journey from Albany Oregon to California along what is now Interstate 5.
I love this letter for its sweet expressions of love, and for John’s vivid description of coach travel in the late 1800s in Oregon. Whenever I’m stuck on a plane waiting to depart, I think of John on the freezing floor of the coach, on page 2.
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Dog Water Bowl Scale Part 3: Final Assembly and Installation
In my previous post, I covered the mechanical construction of the scale. In this post, I finish assembling the scale, calibrating it, and installing it.
After painting I put feet on the scale so it won’t soak in water spilled on the floor.
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Dog Water Bowl Part 2: Measure Twice, Cut Once
In my previous post, I started working on the scale. In this post, I finish the woodworking, and painfully re-learn the woodworker’s adage: “Measure twice; cut once”.
I was so excited about the progress I’d made, and so eager to finish the drilling that I carefully measured, drilled the holes for one half of the Load Cell, then counterbored the hole for the first Load Cell nut… then discovered in my haste I’d counterbored the wrong side, and ruined the bottom plate of the scale.
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Dog Water Bowl Scale Part 1: Initial Design Work
Now that my Dog Bed Weight Scale is sending data, I’m going to have a go at a water bowl scale. The idea is that, like the bed, the bowl will periodically send its weight to a cloud. This data should tell me when Pippa drinks, when we refill her bowl, and (maybe) how much she drinks.
The work-in-progress sources on Github, contain the beginnings of the Arduino 101 Sketch, Bill of Materials (Parts List), mechanical design/construction details, and a day-by-day project diary.
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Dog Weight Scale Part 16: Data!
In my previous post I changed the uploader app to run when the Raspberry Pi turns on, and installed the scale under Pippa’s dog bed. In this post, I get interesting data from the scale.
The scale has been running for a little over a week now, and has been surprisingly reliable for a first version. There is some sort of bug in which, every few days, the scale stops supplying new data BLE notifications to the gateway. I plan to refactor the scale and gateway to avoid that, but that’s another post.
Today I looked at the data and saw some very interesting things.
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Dog Weight Scale Part 15: Scale is Installed and Uploading Real Data
In my previous post, I wrote the Raspberry Pi Node.js code to upload data from Pippa’s dog bed scale to data.sparkfun.com (update: site is down in 2021). This post covers how to make a Node.js program run automatically when the Pi is turned on. Oh, and at the end I installed the finished scale under Pippa’s bed.
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