Matthew Petroff Tue, 01 Apr 2014 22:22:55 +0000 en-US hourly 1 Quadcopter Landing Skids Fri, 07 Mar 2014 02:21:24 +0000 Continue reading ]]> One of my quadcopters recently had a hard landing that broke its landing skids. The skids that came with the frame kit consisted of 5mm carbon rods with flimsy plastic joints, and the crash broke both. I decided to replace the skids with a more durable pair by replacing the carbon rods with aluminum and the plastic joints with sturdier 3D-printed ones.

Landing Skid Joint

Once on the quadcopter, the new landing skids had similar give, but since they’re aluminum instead of carbon fiber, they should bend much more before breaking.

Quadcopter with New Skids

Update: The aluminum bends pretty easily, bending even if the landing isn’t that hard. Fortunately, it’s very easy to bend back and can survive a much harder landing than the original carbon rods.

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Snowy JHU Aerial Photos Sat, 15 Feb 2014 00:03:40 +0000 These photos were taken at Johns Hopkins’ Homewood Campus from a quadcopter the day after a snow storm.

MSE Library

The BeachGilman HallKeyser Quad

The full set is on Flickr.

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HTML5 Night Sky Viewer Sun, 09 Feb 2014 23:41:29 +0000 Continue reading ]]> For HopHacks last weekend, I wrote an HTML5 night sky viewer. Using D3.js and SunCalc, the 750 brightest stars are rendered using SVG and Javascript. One’s location can either be found using the HTML5 Geolocation API, or it can be entered manually. The keyboard is used to navigate, and mousing over a star will display some information about it. As it was written in a weekend, there may be bugs.

Here is the viewer:

The code is available on Github.

Night Sky

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Camp Workcoeman Website Redesign Tue, 21 Jan 2014 00:04:26 +0000 Continue reading ]]> I spent the last few weeks redesigning the Camp Workcoeman website. The site design is based on Bootstrap, without the jQuery components, and makes heavy use of SVGs. In addition, the header dynamically responds to the time of day—the sun’s out during the day, and the stars are out at night. Using SunCalc.js, it fairly accurately displays the sun and moon. Jekyll is used for templating and site generation.

New Site

Compare this to the old site, which was completely static HTML and Flash, making updates difficult.

Old Site

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Perambulations and Town Lines Sat, 28 Dec 2013 04:19:04 +0000 Continue reading ]]> Although abolished a few decades ago, for much of Connecticut’s history colonial, then state law required that towns regularly perambulate their boundaries and establish and renew bounds on said boundaries under penalty of a fine. This was to be done every year at first, before being changed to every three years and then every five years during the 1800s, before being struck from the books. This timetable was not always followed, as I was only able to locate perambulations from 1812, 1849, 1860, and 1914 in the case of the New Hartford and Barkhamsted town line. Perambulations were more frequent in the case of the Winchester and Barkhamsted line, although I only located the 1885, 1900, and 1921 perambulations. I’ve typed both perambulations, making some minor formatting changes and spelling corrections. Here are the New Hartford / Barkhamsted perambulations and the Winchester / Barkhamsted perambulations.

Quoting from chapter two, section fourteen of the 1866 Connecticut General Statutes, “Every town shall procure its bounds to be set out by plain and durable marks and monuments, which shall be a large heap of stones, or a ditch six feet long and two and a half feet wide, or ordinary depth, at every corner, and once in every eighty rods, in the lines running from corner to corner.” I have located most of the bounds closest to the southwest corner of Barkhamsted. Most of these bounds are stone cairns with the town initials carved into a stone on the top. Unfortunately, these bounds have not been renewed in close to a century, and I was not able to locate all of the bounds I looked for. Of the remainder, most were in good shape, although the letters carved into the stones were worn and difficult to read during the summer. In addition, the large flat rock marking the four-corners of the towns of New Hartford, Barkhamsted, Winchester, and Torrington was disturbed and is cracked in two.

Below is the second bound on the Winchester and Barkhamsted town line with snow making the markings clearly visible.

Winchester-Barkhamsted Bound #2Winchester-Barkhamsted Bound #2

Update: I have since found copies of 1858 and 1866 perambulations of the Barkhamsted and Winchester town line as well as the original copy of the 1860 New Hartford and Barkhamsted perambulation in Henry Norton’s survey minutes in the Connecticut State Archives (RG 069:037).

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