LAN-connected Washing Machine Lets You Know When Your Clothes Are Done


[Micha’s] washing machine is equipped with a rather inaccurate timer, so it is always difficult to estimate when the load will be finished. Since it is located in his basement, he hated having to check on the machine continually to know when his clothes were done. Instead of hauling up and down the stairs over and over, he decided to hack in an “end of cycle” notifier of his own.

The washer has an LED that lights when it is finally done doing its thing, so [Micha] removed the LED and soldered in two wires, which he then connected to his Arduino. When the washer is finished and the LED should be lit, the Arduino senses that the input has been pulled low, signaling the end of the cycle. The Arduino was hooked into his home network via an Ethernet shield, enabling him to monitor the process from the comfort of the nearest web browser.

It’s a clever implementation, and it sure saves him a lot of time trudging up and down the stairs. Nice job!

44 thoughts on “LAN-connected Washing Machine Lets You Know When Your Clothes Are Done

  1. This goes far beyond applications in a single house-hold. I have long sought the laundromat which let me explicitly schedule time for a washing machine. Having a real-time display of current activity, along with historical usage data, would go a long way towards more efficient laundromat resource utilization.

    Anyone who has ever lived in a large-acreage apartment complex with a single, six-washer laundromat room would probably know the pain of which I speak, especially when you have to make six to eight repeated trips, speculatively carrying your laundry just in case a washer is actually free.

    1. Well at my dorms in college all of the laundry facilities were networked and you could log on to a webpage that would show you the statuses of all the machines and time left, etc. That technology has been out for a while but most apartment complexes are too cheap to implement anything like that.

      1. I looked into tapping into my G.E. washer for the reason stated in the post (the timer is really inaccurate).

        I’m sure others have tried. The main hurdle is the board is designed to have 120VAC all over. Only a few traces are DC or a reasonably low voltage.

    2. In our apartment complex, we had a paper calendar book where people would write their names on the hour that they wanted to use the washing machines. By the house rules, if you didn’t show up, the next person could grab the machine after 5 minutes past on the clock in the room.

      That worked perfectly fine even when people reserved more time than they actually needed, because you could just pop your laundry in if the machine was free.

      Then the company removed the book and made a web-service instead, and it all went to shit. Now you have to find a computer to check if a machine is available, and you only get six reservations a week, which means a maximum of three loads of washing and three times on the dryers.

      1. It’s not that the timers are “inaccurate” — it’s that a portion of the time (a potentially significant amount of the time) is spent filling the tub with water– at least on a traditional machine. The rate of fill and the amount of clothes both can vary, and this results in cycle times that can vary quite a bit. The “timed” functions of the wash cycle will always be very near to exactly the same, second-wise, but the timed functions have to wait on the fill processes to complete. The drain can also take different amounts of time, but typically not by much, unless the load selector (small, medium, full, extra, depending on the model and it’s features) is changed. (“full” loads take longer to drain than “small” loads)

        Another aspect of timing, again having to do with the fill, is the wash water temp- your choices are generally hot (all hot water) cold (all tap water) or warm (both hot and cold are used “equally”). If you watch it fill, you’ll probably notice that filling with “hot” takes longer than “warm”, and “warm” will take longer than “cold” (tap water, which may or may not be actually cold!).

        So yes, the times will vary, but no, it’s not the timer’s fault. ;)

        I’m working on a washer design that will fill a reserve tank set above the washer during the agitate wash cycle (timed) for the rinse cycle and fill it again during the agitate rinse cycle (timed) for the next load. The idea is to have a 4- or 5-inch pipe from the reserve to the washer so that filling happens as fast as possible without getting water everywhere. I think I can cut a typical wash cycle in half with this method, but we’ll see. I’m sure you’ll find it on hackaday when I publish! :)

  2. man this is the kind of post that makes me yell a 5 letter word…. “SMART” Why can’t all the washers and dryers have this. They would probly chare 200 more for that any ways. and this hacker done it on the cheap.

    1. Probably voiding the warranty. ;) Not a problem if the unit has outlive it’s original warranty, and/or any purchased insurance warranty plan. Detecting the light output of the LED could avoid internal modification, and possibly make it portable to other machines.

  3. Most dryers, going back to the nineties at least, have a ‘more/less dry’ setting that is supposed to be more efficient than using the timer anyway. There’s a moisture sensor in the dryer that detects how much moisture remains in the load and shuts off after a given point.

    That said, this is a rather cool idea. It could use some refinement, but for a proof of concept this is great. I probably would have wired in a really loud buzzer. ^.^

    1. LOL my dryer wen too when I was reading andar_b’s comment. My dryer’s main control has a setting that supposed to turn off the dryer when the cloths reached a predetermined level of “dry”, generally I have to run the dryer 30-60 minutes more. No I’m not over loading it, and yes the lint filter is clean.

  4. I would have done this differently, using a sensor to detect LED on/off, attached to the Arduino.

    Actually I’ve been working on a similar problem: wireless detection of washer/dryer state 100′ away. I’m using a Zipit Z2 device running embedded Linux (with wifi), along with a microphone. The goal would to sample the noise every minute or so, compare it to “washer going” or “dryer running” sounds, and send info to another machine.

    1. They had it in 1996 when I showed up, and I think it was fairly new then. It ran through unused phone lines.

      As I recall someone tried to sue them once for patent infringement, but the MIT version far predated anything else.

  5. Does the amount of time it takes to get done change significantly between washings? Wouldn’t it be simpler to just time it one time and the next time simply set an alarm for XX minutes?

    Also, this reminds me that I really need to do my laundry, bleh! Oh how I miss the old days when you could just dump your laundry in the basket and they would magically become clean (thanks mom!).

  6. This would be perfect for a university dorm (besides of course MIT, they have it, right?) or a condo laundry room, mabye the next version should have a way to enter user info and have the washer email the user when its done. “Come get your undies or I’m eatin’em!”

  7. Great work. I did a similar thing with my dryer awhile back, I used a clamp on type hall effect sensor on the power line, no need for modding. The same circuit could also monitor anything, tvs, computers, coffee pot.

  8. This sounds like a good hack, but if going that far, why not just have it go ahead and send a txt/email. Then you would know without even having to go look…
    (Does this mean I’m extremely lazy or what! :p )
    Just my 2cents worth… Keep on hacking
    Have a Nice Day!

  9. I did almost this exact same thing to monitor a lapidary (rock cutting) saw, which takes 15 to 30 minutes to complete a cut and is in my garage. I used a Parallax Propeller and ENC28J60 and it also controls the feeder and stops the saw automatically if there is a problem.

  10. I have toyed with the idea of a laundry done indicator – would be nice for both washer and dryer. Our appliances are old enough that they just have a dial indicator. (No alarm, etc.)

    If you wanted to get fancy, one could add an accelerometer to warn one of out of balance loads on the washer. (Extra credit if it can tell you where the heavy part is after the drum has stopped.)

    Since control systems are so cheap now it is surprising that basic washing machines still have such limited controls. Even on new machines, if I need it to do a second rinse, or I want it to soak for 10 minutes, etc. I have to do the control by hand. (May be available on fancy machines – but “Iron is expensive; silicon is cheap” – J. Pournelle )

    Such added control and notification would be especially useful for low water use machines. They take a lot longer to do a load of wash than traditional machines, and are more likely to need additional rinse cycles to remove soap or bleach.

    Network connected washers have been around in one form or another for a while. I seem to recall a news item about a project that IBM or some such did in the early to mid-90s. (Can’t find the clipping at the moment.)

    FWIW – Here is a more recent trial:

  11. Seems like overkill. All you really need to do is keep an eye on a clock. If the timer is lousy, just take your time getting down there. An unbalanced load indicator, on the other hand, would be extremely useful.

    The only problems I’ve ever had in communal laundry rooms is when someone leaves their stuff in the washer and dryer for 12 hours at a time.

    Maybe it’s me but doing laundry is just not that inconvenient. Then again, I make it a point not to live at too fast of a pace.

  12. I put an xbee with a tilt sensor on my washer and dryer. When the tilt sensor moves over far enough the xbee starts up, sends a message to another xbee hooked up to an arduino that has an ethernet shield connected to my local network. Shortly thereafter I get a tweet and a light on my mantelpiece lights up.

    It will be great when all of these devices have something like this.


  13. Dude, try a Baby Monitor! Stick the one next to/on top of the machine. You just stick the receiver wherever. Then you can just turn it on and hear what is going on. Most also have a VOM so you can see it as well.

    Also I would have been fine with an extension LED coupled to the machine’s original that is ran into the kitchen or whatever. If you make a cutesy housing for it, could be cool.

    Bravo on fixing your problem and learning a little Arduino skills in the process :)

  14. our house-owner installed some cheap wlan-webcams and an open wlan only for these webcams, so everybody in the house can see if a machine is free. maybe the easiest solution ;)

  15. Just wanted to make a comment regarding shock hazard. Many of the low voltage supplies in appliances are not isolated from the incoming AC power. It would be much safer to use a method of detection which does not require electrical connection.

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