Ikea Standing Desk Goes Dumb to Smart on LIN Bus

IKEA’s products are known for their clean, Scandinavian design and low cost, but it is their DIY or “assemble it yourself” feature that probably makes them so popular with hackers. We seem to receive tips about IKEA hacks with a consistent regularity. [Robin Reiter] has a Bekant Sit/Stand motorized table with buttons to raise and lower the surface, but it doesn’t have any memory presets. That’s a shame because it requires a lot of fiddling with the up/down buttons to get it right every time. It would be nice to press a button, go grab a Coffee, and come back to find it adjusted at the desired height. With a little bit of hacking, he was able to not only add memory preset buttons, but also a USB interface for future computer control.

The existing hardware consists of a PIC16LF1938 micro-controller with two buttons for movement control and a LIN bus  protocol which communicates with the automotive grade motors with integrated encoders that report position values. After a bit of sniffing around with his oscilloscope and analyzer, he was able to figure out the control codes for the motor movements. For some strange reason, however, the LIN signals were inverted, so he had to introduce a transistor signal inverter between the PIC master and the Arduino Nano that would act as a slave LIN node. Software was made much easier thanks to an Arduino library developed by [Zapta] for the LIN Bus signal Injector, The controls now have four buttons — two to replicate the original up/down movements, and the other two to act as memory presets.

The code, schematic and a simple wiring layout are posted on Github, in case there are others out there who’d like to replicate this hack. Check out the video after the break where he gives a walk through the code.

24 thoughts on “Ikea Standing Desk Goes Dumb to Smart on LIN Bus

  1. Great hack, although I might have just taken the whole stock controller out. He already interfaces with the lin bus to read out the height, it should be fairly straightforward to write to the motors directly and tell them what to do.

    1. Well the problem is that if you remove this board the LIN master is gone. There are several other packets that get sent and you have to first figure out what they do and then reimplement them.
      Then, the position values that get sent are somewhat special. I’m guessing they implemented some acceleration/deceleration stuff. But I don’t know for sure.
      It was just a lot easier :)

      1. There are Versions of such Controllers with only two Buttons which have memory.
        Some only move as long as you press some button, others do move to their position automatically.
        Some switch modes when you double press one button.
        Mostly they have some display to display whats going on.

        Also the connector to the membrane keyboard has 7 connections, if I recall it correctly, so there is room for more.

        My PCBs have hints they may be developed by http://www.intertek.de or maybe they are just tested by them.

          1. AFAIK IKEA only sells the version we know, worldwide, if it’s sold there at all. (The control is about 25€ as a spare).
            The legs and control are supplied to ikea by some third party for shure.
            You can search for other tables with memory and their manuals for inspiration.

  2. Nice hack. Hope the desk lasts longer than a year.
    On a separate note: I don’t know why people like IKEA or their furniture. Swedish Walmart with refaced Sauder pressboard is super cool. I think the catalog is probably my favorite part with all of the soupy inspirational quotes “It empowers me to nourish my child” etc. Then there are the unrealistic room setups where a kid would have to close the Murphy bed, drain the sink, move a tAble` slab to cover it, then put up the Lego catcher, pull the privacy screen covered in agnostic squares, and move the jar of fresh dill under the sink just to play with Lego bricks smh.

    1. The funky euro-style isn’t for everyone, agreed. They do have plenty of traditional furniture too.

      For the laminate and veneer pieces the design and quality of Ikea is much higher than Sauder / Wal-Mart dreck. Not all pressboard is made equal, and how Ikea designs tends to avoid the stress points and weak joins that plague cheap flat pack. The way they standardize design points across a range and build for mix-and-match construction on certain pieces make ‘furniture hacking’ easier.

      Most of the better Ikea furniture is also either fully solid wood or a mix of solid and plywood / pressboard. Because of their manufacturing process the better stuff also tends to be affordable for more people.

      Room setups are always ridiculous ideals, and the “mini room” layouts both work well in a store and illustrate possible layouts for space-constrained Europeans – their target market. Check out Pottery Barn or Restoration Hardware for more Americentric versions of the same silliness.

      Ultimately though, if it ain’t your thing it ain’t your thing. No worries.

      1. We had a Wal-Mart entertainment center that managed to survive a couple moves. On the third move, it spontaneously and instantly folded itself nicely into a flat pack again on a trip up the stairs. It was the last trip it made.

        That said, yes, Ikea furniture is way better and strikes a nice price/performance tradeoff for many people.

    2. As a European, let me explain:
      1. Our houses are smaller and ikea is good at producing devices which take advantages of smaller space.
      2. They strike an excellent price-performance ratio.
      3. They are low price because of mass manufacturing, any other furniture chain will sell the same quality for more.
      4. Because they are cheap, you can change your whole house every 10-15 years and not be bankrupt.
      If you move between countries you will realize that
      5. It is sometimes cheaper to sell the old one and buy new than to ship your furniture.
      6. You will spend little time picking new one up, because you know what is available, all stores sell the same thing.

  3. Not knocking the project by any means, but couldn’t you wire up a new switch to the existing button contacts for up/down and use a pair of limit switches at the desired heights to cut the juice? Isn’t as flexible perhaps given the limit switches would have to be rigidly mounted relative to the floor, ceiling or perhaps just the table legs.

  4. Those with limited budgets might try alternatives. Instead of a standing desk, get an art/craft/drawing table that elevates and tilts. They cost less new and thrift stores often sell them for under $20. Just make sure it’ll go high enough for use standing..

    If you’re space is limited, look into collapsible drying racks for clothes. The wood ones tend to be flimsy, but most of the metal ones are study and stable enough to work with a laptop or tablet. Best of all, they collapse, so you can fold them up and put them away. Thrift stores often have them for under $10.

    Both illustrate useful life hacks. Things for computers and offices often have inflated prices, perhaps because a business is covering the costs. Look for that same functionality in a more frugal and competitive arena, and the markup isn’t nearly as great.

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