I Hacked My Standing Desk with a Raspberry Pi | Hacker News Reader

I Hacked My Standing Desk with a Raspberry Pi

medium.com

Good on the guy for getting his goal over the line! Not the most elegant approach perhaps, but it works and going from nothing to working is worth a lot.

I'm with the group that thinks a Wemos D1 or other ESP8266 micro is probably a better match for the application (if you want to keep open a Wifi control option; if not, literally any microcontroller board would be fine), but if you know Linux and python and not C or have never touched a microcontroller before, not a lot of harm in going for the PiZero.

What I like about microcontrollers is that they just work for years on end. I've got one at home that's been running for about 10 years now, untouched (which makes sense, since most of our gadgets work that way as well).

Yeah, this is certainly not the most elegant or efficient solution to the problem in terms of power usage, processing power, etc. But honestly, I don't really care.

My criteria were: 1. What's easy? 2. What's cheap? 3. Raspberry Pis are cool. I wouldn't mind playing with one.

I actually have programmed a microcontroller in C before (an Atmel Butterfly) but that was... 15 years ago? I haven't written C in at least 5 years.

I'm fairly optimistic that the Pi would have continued for years. It has no connection to the internet, and the code is extremely simple. If I were designing a device that somehow needed to run without being touched for 10 years, then definitely a microcontroller would have been the way to go. Or maybe even just a timing circuit, no processor involved.

Totally understand, I enjoyed the writeup, and applaud the outcome; thanks for sharing it!

Well, instead of a teensy, the esp32 is sure a good bet.

But since you've got the Pi, the next logical step is to get an rtc upgrade and run chrony/openntpd and a backup dns cache. Why not? I mean its right there on the desk. Could add a quick binary clock for practicality.

Since you might now be dependent on the thing, its easy to add snmp for monitoring, hack in some rrdtool or whatever to graph your sit/stand time, maybe a serial connection to monitor your UPS power situation, and you get a free Pi-hole by now! Probably a little overkill to run wireguard on the thing, though.

But honestly, why stop there? Have it control some functional LED lighting[0] (Zack uses an ESP32 instead of the pi--must not care about clock drift. The biometric sensor is also a little expensive and uncomfortable looking.) with suntime[1] for a perfectly and coherently illuminated environment.

For the extremely paranoid, yet lazy and obsessive (who does that not describe?) you can grab an extra wifi dongle with raw monitoring mode to have some fun with trackerjacker[2]. Use an innovative static base station running map mode, so when an influx of unknown devices with increasing strength and/or known vehicle SSIDs or PAN beacons are detected, just go full Red Alert (using those very practical leds) and score a quick win by raising the desk and commanding your IoT lighting for a deft escape.

Maybe you can use this for the girlfriend too, since by now you've already got rrdtool or cacti or whatever graphing the desk height and trackerjacker output from her iPhone and Jeep Latitude hotspot, you could also use that capability to gain insight as to when it should reach out and trigger your coffee maker's ESP32, certainly while raising the desk.

[0] - https://www.youtube.com/watch?v=g6n8XLmZ__I

[1] - https://github.com/SatAgro/suntime

[2] - https://github.com/calebmadrigal/trackerjacker https://reconshell.com/trackerjacker-maps-and-tracks-wifi-ne...

I have a similar desk and I was going on a similar path before I noticed the company that made the desk’s motor has a BLE adaptor for 15$ which solved my problem completely.

My desk was made by LINAK, who also provides some IKEA standing desks too. Here’s the adaptor if anyone is interested: https://www.linak.com/products/accessories/bluetooth-adapter...

I use a script that’s triggered with a keyboard shortcut which I find super cool.

That BLE adapter plug looks very similar to the port where the controller plugs into for my Ikea bekant standing desk. I'm curious if it works with the bekant. Since same company makes parts for Ikea. thanks for the link. Do you know where I can purchase that adapter? Preferably in the U.S or have it shipped to the U.S?

Some IKEA desks are Linak but I'm not sure if Bekant is.

I got it by reaching out to a local distributor of Linak products in my country as I couldn't find any online website selling it at the time. You might try that, they might even know if it's compatible (or at least would know how to check).

Oh, I would suggest getting the new controller instead of the dongle since that one supports both BLE and it has physical buttons which is always great.

That would be amazing.

Well that's nifty.

This reminds me of many years ago when the entire office got motorized sit-stand desks. We had frequent competitions ..3.2.1.<Who can raise their desk quickest>. Utterly pointless as all tables raised with the exact same speed* but very funny. One day the repair guy came to the office and I explained the situation to him and he somehow managed to tune the electric motor in my desk, so it would raise my desk a lot quicker than the others. The look on the others face when I unleased my new super power. priceless :)

I wonder if the pi would have beaten me?

*Desks with the same number of monitors (weight) would raise with the same speed.

For me the major inconvenience is having to add yet one more power adaptor to typically overcrowded socket outlets. I wish we had a common system of power adaptors that allowed to get some volts from already existing plugs! I reckon this wouldn't always work, but it should be possible to get the power required from a Pi Zero from practically any already existing supply...

I have the same complaint. My standing desk already has about 6 different power bricks and a few more plugs all of which have to be carefully wrapped and stuffed into a cable keeper.

The solution i am working on is that i am repurposing a PC power supply and then bought several high amp buck converters. I am wiring the 12v and 5v rails to the different buck converters to get the required 19v for my monitors, 24v for speakers, etc. All of this is a single unit much smaller and I can cut the wires to length to reach each device exactly.

A few years ago, I saw these[0][1] on a daily deals site and I picked up a couple. There are a number of them floating around the internet and I'm sure some other manufacturer makes something similar.

They work really well for a small(?) constant load. I use mine for a Chromecast because my TV doesn't have always on USB ports.

My only complaint is that it's a little large, so if you have a tight configuration on a powerstrip, it might not fit with other bulky adapters in the adjacent slots.

0: https://www.walmart.com/ip/Twist-Charge-USB-Charger/33490454 (Walmart link because I'm sure it will stay around after they're sold out).

1: The meh.com listing with more information: https://meh.com/forum/topics/2-for-tuesday-bracketron-twist-...

That's an interesting invention! I'll check if there are european versions, thanks

Buck-boost converters can be bought for like $2. I'm sure the pi could have been powered off the voltage going to the button panel.

Came for the massive overkill, stayed for the abysmal soldering!

It gets worse: check out the comment above about adding chron and NTP with a Wi-Fi dongle...

Doesn't anyone know how to program an MCU timer anymore? I mean, prescalers and clock trees really aren't that scary...

I've been using a Pi for some similar timers, and given the price-point, there's a lot to be said for them. The most relevant example here would be one that reads my calendar (ical over http) and only fires on days I'm working. "Doesn't fire when I'm in a meeting" wouldn't be a huge stretch either. Or at home, "doesn't fire if the lights are turned off" would stop the desk bouncing around when I'm not working.

I'm not sure NTP over wifi is a big deal either. The problem space here isn't millisecond accuracy, it's regaining time after a power-off, as the pi lacks an RTC.

Yeah I get it: it's a fun hack to learn about GPIOs and REST APIs. But it's a solution to a lack of self-discipline, which I find offputting.

A short while ago I tried to replace a 5mm x 5mm surface mounted push switch.

It didn't go well. Now I am learning KiCAD...

Guilty as charged... but hey, it works!

You're not wrong.

Less worried about the Pi, and more worried about a big heavy thing moving about on its own on random time intervals. Do these desks have some sort of torque-exceeded safety shut off that keeps from squishing your cat or similar?

Mine will stop if something gets in the way or bumps it. The ones I had at work before COVID were the same and made by a different company. As another user said though, they can be a real pinch hazard. Had one cut a cable once.

Some standing desks require you to hold the button when they move, presumably so that they could skimp on the testing requirements and/or hardware needed to safely stop when the desk hits an obstruction.

BTW, this is often totally undocumented (often blatantly on purpose) and you basically need to find a video review of the desk in question where you can see the desk move on its own or else it's not guaranteed it will do that & you will spend a ~minute every time you want to rise or lower the desk to the standing/sitting position.

Do you think that particular model would still stop, if some DIY hack had "hotwired" the button inputs to its controller?

Why would its behaviour change? The hotwire is just replacing the button. The desk would react the same way if a human hit the button

I don't know. For example, would the mechanism that stops the motor on resistance work properly in a given product model, if (from its perspective) the human was holding down the button, or pushing the button repeatedly, even when there was an obstruction?

Another thing I'd also look at, for a particular model, was how faithful the electrical/mechanical interfacing of the hack, and whether that had implications for system operation safety.

Yes. I assembled the desk myself. The motor controller is a separate unit from the pin pad.

The desk, at its lowest sitting position, still has plenty of clearance for nearly all household pets or unsupervised infants.

My thought was "Save yourself some time/effort and do what I do: set a timer to remind you to stand."

Looking at the picture, it's in close proximity to other horizontal surfaces at similar levels.

Mine has a so called "active anti-collision", I've seen it in action once when I forgot my chair was still rolled under.

https://www.zenspacedesks.com.au/product/professional-series...

(Author here) Yeah, this. I probably wouldn't have done this if the desk hadn't had an anti-collision feature. I made an edit to the article to explain.

Generally no, the desk is a serious pinch hazard since it is so heavy!

It would be hard to detect a problem going down since the leg could just lift off the ground.

If it were me, I'd add a quick warning beep about 5-10s before actually doing the lifting.

This is a cool project.

Edit: removed my stupid comment about leaving stuff exposed to the internet - that was a DIFFERENT article I read about a similar project after this one! [0] My bad… it’s late here…

TLDR; this article inspired me to go down a rabbit hole…

[O] https://medium.com/google-developer-experts/hey-google-set-m...

Nothing’s exposed to the Internet here. The pi zero is part of a closed loop.

Oops - see my edit!

My first instinct was also to wince when the Pi Zero came out, since this is a very simple application, perfect for, say, Sparkfun's Arduino Pro Mini.

Which is ten bucks. A Raspi Zero is five bucks. Sure, there's... something elegant about using less computer for more money but... what?

I'm sure someone has a link to an Alibaba ripoff for like fifteen cents (might even be why I'm saying this) but like: five bucks and you already know Linux?

Really, why not?

Here's a few of my reasons:

* Patching/attack surface. I don't want to maintain a full Linux OS, and I expect (hope) that the network stack on something like an Arduino or ESP is both secure by obscurity (I know...) and by lack of functionality.

* Some things are much easier on a simpler chip as well, like bit-banging access to a NeoPixel, due to the lack of a multitasking OS.

* Bootup times on simpler chips are mostly imperceptible. They power up and begin running your code. (Arduino includes a short pause you can remove, or you can bypass the Arduino boot loader entirely and program the AVR directly.) Even the slimmest of Linux distros can't beat it.

Ok, those are all good reasons to choose Arduino, for some other applications of which this isn't one.

I would also just use an Arduino here, I've got a box of tiny ones (Adafruit feather) which would be plenty for this application, and I'm already familiar with the platform. From bit-banging Neopixels, as it happens.

But for running an incredibly simple cron job on a standing desk, none of these are compelling. It makes perfect sense for someone who knows Linux, and doesn't want to learn Arduino, to just break out a Raspi Zero and do what he did here.

It's air-gapped, so the risk of it getting pwned to mine Monero or whatever is pretty minimal. There are no real-time considerations for an action which happens once an hour +/- a few minutes, and boot-time for an application where the first action is around an hour from power-on is also not decisive.

The SD card is another one, the Pi will be logging and constanly reading and writing to the SD card until it eventually fails.

It's 3 characters to switch it to read only mode, and just a few more to save the system clock across boots.

Surely the raspi linux distro has that disabled by default?

It does not.

Realistically the attack surface of a Linux running almost nothing, in a local network, is also very small.

Pi Zero isn't really 5 bucks. At least not anywhere i have ever found. All official dealers who sell it charge a minimum of $6-7 shipping and also limit you to a single unit per order.

The best deal I have found is ordering from adafruit where you can get 1x with headers and 1x without headers. Then you end up paying only $8-9 each. And that's for the zero. The zero W (wifi) is $10.

If you are lucky enough to live near a micro center, they sell them at the correct price "over the counter", in person only. They limit you to one per transaction to avoid reselling.

My parents live near one of the stores, and I will always stop in to grab one.

I think the real value is the Pi Zero W. Stick them in appliances wall over the house. SSH into them if you like. Send them over the air updates. Program them with the same Linux tools you know and love.

Also, as far as I know there aren't a ton of Pi clones, since it's not fully open hardware. I believe the Broadcom chips in there are pretty closed.

A few years ago I thought it would be funny to reverse engineer this same desk and add a small wifi board inside the control box. There is even a digital signal which controls the number display

My plan was to slowly move the desk up while keeping the display the same, or something else nefarious like that.

Nice (very quick) hack.

I was hoping to find something about how he was reading the stored height information from the desk so that he could either automatically or over SSH set the desk to specific heights though.

His hack just moves the desk up for a second approximately every 50 minutes. So I guess he just lets it go to max height when he's away, manually sets the height to where he needs it to stand, and just goes back to sitting whenever he feels like it.

Those 1, 2, 3... buttons on the front are presets they already configured. It's triggering their "standing up preset" button once every 45 - 60 mins and then they press the "sitting preset" whenever they want.

(Author here) This is correct. The control box remembers my ideal standing height and goes directly to it on one button press.

"Wha- where is all of this traffic coming from?" *checks stats "Oh..."

Anyway, I'm the guy in the article. AMA.

Have you done any productivity hacking in the new office?

Epic lol - it goes up. It goes down. “The hardest part of my life was pushing the single button when a random timer went off- fortunately I have a lot of free time” rofl

Wow, Medium.com pages load slowly these days.

Stop writing on Medium.

Was the soldering done blind folded? Even that wouldn't explain the fact the strands were not twisted or tinned or anything...

Good for the author, but the article leaves "MOM GET THE CAMERA!" impression.

>Then I just plugged the Pi into a USB power brick, and… it worked!

Might as well attach a diesel-fueled generator and a pentium 4 to the back of the desk.

The project seems like a perfect opportunity to play around with some arduino-like board. It could probably be embedded inside the control panel and powered from the desk itself.

> Good for the author, but the article leaves "MOM GET THE CAMERA!" impression.

I agree but still think there's value in having this kind of content abound on the internet as it gives beginners with zero experiance a good starting point.

> Might as well attach a diesel-fueled generator and a pentium 4 to the back of the desk.

Maybe but it's 5 bucks so who really cares.

Reply on news.ycombinator.com