My wife and I recently adopted Penny, a wonderful dog from the Denver Dumb Friends League shelter. She’s been a dream in terms of behavior and disposition, however as dads everywhere say, “A dog is a huge responsibility.” I often have meetings and need to leave her in her kennel while I’m gone. My wife may want to know how quickly she has to come home to prevent Penny from being locked in her kennel for too long, and sometimes I turn my phone off for meetings. The solution? An automated web page that records the status of the kennel, and if closed, when the door was closed.
Use the Raspberry Pi running the ‘Raspian’ OS to automatically sense a switch on the dog kennel door.
Use a Python script to read the switch and write the status to an HTML file.
Run an Apacahe Server on the Pi to make the HTML file.
Setup port forwarding on my home router to allow other networks to see the html file.
Use the simplest method to get something running quickly.
The project went really well! I am lucky enough to me a member of Denver’s hackerspace, Denhac, where I tinkered with things and learned from some experienced folks on the weekly Tuesday night hangout. I had some problems with the IP address of the system, but after a restart the issue seemed to go away.
Here is the python script and some notes I took along the way to help anyone looking to recreate my work: raspberrypidogdoorprogram
I took the server down for a few reasons: First, I don’t understand network security enough, and I’ve read that the setup I used isn’t very secure when forwarding ports from the outside world. And second, I get curious occasionally and prefer to have the system on my desk for more tinkering. Finally, the wife seemed to think that this is like taking a sledge hammer solution to a thumb tack problem, which is probably true. But it’s still cool that it works!
For those who know me, beer isn’t just about the drinking. It’s also about the brewing. I’ve casually brewed beer for years, only getting serious with my own setup a year ago. However brewing in front of a stove can be annoying especially when trying to brew 2 different batches at once. To make the experience better, I created a system that meets the following goals:
A pair of electric kettles based on the system that The Electric Brewery creates, running off a dryer outlet.
Variable power set with a knob, similar to a stovetop interface
The ability to shut one side off for only brewing one batch
Kettles that unplug from the system as to not disturb the other batch
Running off a microcontroller that allows for future design improvements
A quick and easy design, enabling fast development and implementation
I’ve got the entire system up and running, and it works great! I’ve already brewed one batch and I have plans for friends to come over this weekend to continue the fun. I’ve posted all of the design files at Element14, including a BOM (Bill of Materials) so anyone else can build, enjoy, and improve upon the system. Here’s a video of me showing it in operation:
I love watching how the growth of spaces like my own Denhac develops as people begin casually making things. Recently Denhac held a surplus sale and I think it really pumped up interest and made the space all around better. There were a few things that I noticed made it a success, so I wrote an article at Element14 about what was so great…
….The sale gave the space an opportunity to quickly figure out if any of the unused donated equipment and books are worth anything. What’s the best way to find out what something is worth? Sell it! It also allows the community beyond the membership circle to grab things that can be used for cool potential projects. I know that it can be difficult for hackers to let things go. All members have 10 projects on the pyre that could potentially use the spare parts, but there’s just not enough time to make it happen! Encourage the members to either start the project or let the parts go to someone who is ready to use them…..
I was recently thinking about how little time exists between a design being ‘completed’ and when it needs to be revised. Obsolete parts, bugs, manufacturing equipment changes, manufacturing locations and volumes will all drive changes to a design. Sometimes is makes a mockery of revision control systems.
My most recent Element14 article highlights the work maintenance and legacy engineers do when crisis hits, and how that can make for a great career opportunity.
I’m always happy to say it: maintenance people are the ones who keep the world turning. This isn’t worth noting because their job is fundamentally harder than other jobs. It’s not because they do something that others cannot. It’s because theirs is a craft of delivering, and delivering now. In addition to having the skills to take another person’s work (or errors) and make them sing again, these men and women need to respond instantly and be at the top of their game until the job is done.
I love everything about kits. I build what I use, I know how to fix it, and I can get any part I find broken. It is sad that there aren’t more people that are into this sort of thing because the DIY-ers don’t represent a significant enough portion of any market to drive manufacturers to offer their products as kits. Given that we are currently in full last-minute-gift-shopping mode, I thought this article about why kits are the way to go would be well timed:
…Now as I am older (read: paying more bills) I find myself identifying with some aspects of minimalist living. Living this way makes me lament the fact that more products aren’t sold as kits. I understand the reasons behind kits being unpopular: it is easier to buy than build, and the prices are lower thanks to cheap, non-serviceable production completed by people working for low wages.
But what so few consider is the inevitable occurrence of a ‘cheap and easy’ device breaking. Or worse, when an expensive name-brand device breaks because the manufacturer decided to offshore production and ‘optimize’ the design for cost savings. I’m tired of stuff breaking almost as often as the R/C car I’d drive off ramps at 25 MPH. What really drives me up the wall is when I attempt to repair it, finding that the device was designed only to make it beyond the 1-year warranty period and NEVER be serviced. Even when I do get into the device and determine root cause, finding a replacement part that I can buy for less than 50% of the entire unit’s purchase price is unlikely…