[Jody] wanted to know when his garage door was open. He details his setup which uses a temperature sensor read by an Arduino to send over XBee radio to a computer running a Windows Service. We have seen this twice before, and is noteworthy as a lesson. The XBee radios have the ability to read analog data, relay digital signals, and a lot more. This means the Arduino is completely unnecessary. For example, the Tweet-a-Watt uses two of an XBee’s ADCs to measure voltage and current in a Kill-a-Watt power meter. Programming an XBee is really simple, with the help of tutorials from SparkFun and Adafruit. A bit of programming and soldering should get [Jody] back his Arduino. We hope this note will help you find more creative uses of XBees without microcontrollers.
[Via Make]
@Jody
Hey, everybody’s gotta start somewhere! When I looked at your blog it seemed like you’re more of a CS guy than an EE anyway, and Arduino is a good bridge for that.
I didn’t mean to sound so incredibly condescending earlier, I’m more frustrated with the fact that I feel like no matter where I go I see 10 Arduino projects to every 1 arm, msp430, or PIC project (hell or even just an ATMel project which isn’t an Arduino!). I understand that this is mostly due to the ubiquity of the platform and the fact that a lot of people are learning the ropes with it, but I really don’t like to see things like “How to read the datasheet for Arduino!” or “How to blink your second and third LEDs, for Arduino!” on sites which are ostensibly for more technically inclined people who’ve probably already figured this out.
And for those who haven’t figured it out, the sites shouldn’t cater to them, it should be a website with projects to aspire to! To inspire them to learn more on their own. I’m not saying that HaD has really fallen that far: the self-playing accordion, building your own 8-bit cpu, and op-amp only segway are all testaments to old school awesome. But sometimes I’m irked by other articles, and I let that leak into an annoyed comment.
The comment aimed at BiOzZ was a response to a somewhat lighthearted insult aimed at people pointing out you could build this cheaply (“come on guys where did you leave your freshmen EE?”). Yes I have a temper sometimes, which makes me totally susceptible to trolling and sometimes makes me an ass.
Sorry if I offended! And good luck on getting into the world of electronics! It’s wild and interesting and there’s nothing quite like knowing that your code has an effect on the physical world.
@Jody, Scuzz
I hope you don’t take anything I said negatively. You used an Arduino for it’s exact purpose. It’s meant to enable those who have very little knowledge of micro-controller and/or don’t want to spend the time delving into endless data-sheets to learn. You had an idea, and Arduino was an easy way to implement it. This is why we see so many Arduino projects, it’s just an easy tool that enables those with unique ideas to act on them; and unique projects get the most views on the web.
If anything I’m more critical of HAD for this. I see HAD as a showcase for those unique ideas, no matter what tools were used to implement said ideas. Sure, projects that clearly better use resources get extra brownie points, (and are good examples of projects to ‘aspire to’) but it shouldn’t be a pre-requisite to get showcased if the idea/project is unique/interesting enough. Heck, if we want to start criticizing projects for hardware efficiency, half the projects on here would be prime for the chopping block.
To openly criticize a project for it’s ‘efficiency’ opens open a can of ‘shoulda/woulda/coulda’ that can be taken to many levels evident in the comments. Who decides what level is appropriate? Everyone has different comfort levels and all of us will never agree on the best solution, so it’s wise to just avoid the conversation all together. Sure, I played the game this time, but believe me it was always to make this point from the beginning.
That’s just my $.02 and I’m sure other people disagree, but none-the-less that’s the way I feel. There’s teaching someone a better way to skin a cat, and then there’s picking someone out to embarrass them in front of the class. To me, this felt more like the latter, and I don’t like that.
Your project shines because it shows someones (with no formal expertise) ingenuity to solve a problem, so props. You clearly are a CS thinker so I can see why you chose the Arduino.
Okay I am not hating on the orginal system or the idea of just using the XBee. In fact both of them made me think a bit.
1. I could use XBees and may home server for lots of sensor type projects around the house.
2. Just how cheap could I build a garage door sensor. I think by scrounging I could do it for free of very close. Get a cheap RC toy and hack the transmitter so it uses some kind of contact switch on the door and then hack the toy so instead of motors it flips a realy or an optical isolator and attach that the a free com port (DTR) maybe, game port, and or an LED. Throw in some wall warts and you done.
3. An improved version of what he built. I was thinking of adding a safety feature. Add a CO dector and tie that into one of the IOs on the Arduino. That way you could use the Arduino to possible open the door and maybe turn on some vent fans as well as have the alarm sound. You could do that all with the XBee and some client server running on any number of devices but then if the server software wasn’t running the fans wouldn’t come on and the door wouldn’t open. You could also have the server software tweet you that something was going really wrong.
The thing here is that this was a great write up because it opens so many new ideas.
Isn’t that the goal?
A lot of the arguments against Arduino were based on the entirety of this person’s example, using a more expensive Arduino and not one of the “bare bones” models. Still more cost wasted on one of the nicer (and more expensive) wireless options.
The problem needing solving is remote temperature monitoring. (Actually it was door open sensing, but whatever..)
A very common application of Arduinos is proximity weather station projects.. how is this usually solved on the cheap?
They just rig really low cost transmitters to sensors.
Consider that you can buy a “JeeNode” (Arduino clone with mini AM transmitter) from Modern Devices… for about $18. This INCLUDES the wireless. Now plug the TMP36 into the JeeNode.
Buy a second Jeenode for a ‘receiver’ (or buy just the radio component sans ‘duino, and connect the reciver to whatever you have… another Arduino, a PC, hacked router etc.)
This neatly fixes the cost issues, without removing the time-savings of using a ‘duino.
Technically you -could- an eliminate the ‘diuno and pair the sensor and radio with a PIC, saving a few bucks. I would not go that far. Let the more embedded solutions dismiss the Arduino as a waste… doesn’t matter if you can do it cheaper with a PIC, because there will be someone out there who dismisses the PIC because you can also do it with just analog circuits.
Note: I’m not bashing any approach here. I was however a bit surprised no one suggested cheaper wireless solutions.
“Note: I’m not bashing any approach here. I was however a bit surprised no one suggested cheaper wireless solutions.”
Many people did, including myself, though most of my posts were a satire to make the point there’s a million ways to make something better and who’s to judge one over the other. Therefore, ‘The only way to win the war is to not play the game’ and we should all go back to enjoying cool projects.
The Garage door itself is overkill why not smoke and mirrors?