linak-controller

(Previously idasen-controller)

Linak make motorised standing desks. They can be controlled by a physical switch on the desks or via bluetooth using an phone app. This is a script to control Linak desks via bluetooth from any other device.

Note: This script may not work with all Linak desks - see below for comaptible models.

Set up

Prerequisites

• Windows / Linux / Mac
• The device should have Python 3
• The desk should be paired to the device.

Working Desks

• Ikea Idasen - works (my desk!)
• iMovr Lander - reported working 43
• Linak DPG1C - reported working 32
• Linak DPG1M - reported working 32

If you find another desk model that works please make an issue to report it!

Install

Install using pip:

pip3 install linak-controller

Configuration

Configuration can be provided with a file, or via command line arguments. Use --help to see the command line arguments help. Edit <config_dir>/config.yaml if you prefer your config to be in a file. <config_dir> is normally:

• ~/.config/linak-controller on Linux
• C:\Users\<user>\AppData\Local\linak-controller\linak-controller on Windows
• ~/Library/Application Support/linak-controller on MacOS

Config options:

Option	Description	Default
mac_address	The MAC address (or UUID on MacOS) of the desk. This is required.
base_height	The lowest possible height (mm) of the desk top from the floor By default this is read from the desk.	null.
adapter_name	The adapter name for the bluetooth adapter to use for the connection (Linux only).	hci0
scan_timeout	Timeout to scan for the device (seconds).	5
connection_timeout	Timeout to obtain connection (seconds).	10
move_command_period	Time between move commands when using move-to (seconds).	0.4
server_address	The address the server should run at (if running server).	127.0.0.1
server_port	The port the server should run on (if running server).	9123
favourites	Favourite heights object where the key is the name and the value is the height	{ sit: 683, stand: 1040 }

All of these options (except favourites) can be set on the command line, just replace any _ with - e.g. mac_address becomes --mac-address.

Device MAC addresses

• On Linux, device MAC addresses can be found using bluetoothctl and bluetooth adapter names can be found with hcitool dev
• On Windows you can use Bluetooth LE Explorer.
• On MacOS you can pair the device with Bluetility, but you must use the UUID instead of the Mac Address.

Usage

The script accepts a number of commands:

Command	Description
	Running without any command will print the current desk height
--watch	Watch desk and print changes to height (and speed)
--move-to <value>	Move the desk to a certain height (mm) above the floor
--scan	List available bluetooth devices (using the configured adapter_name)
--server	Run the script as a server, which will maintain the connection and provide quicker response times
--tcp-server	Run the script as a simpler tcp only server
--forward <other commands>	Send commands to a server
--config <path>	Specify a path to a config file

Moving the desk

To move to a particular height you can run:

linak-controller --move-to 800

If you have configured favourite values in the config.yaml like this:

favourites:
  sit: 683
  stand: 1040

Then you can also pass the favourite name to the --move-to command:

linak-controller --move-to sit

Using the Server

You can run the script in a server mode. This will maintain a persistent connection to the desk and then listen on the specified port for commands. This has a number of uses, one of which is making the response time a lot quicker. Both the server and client will print the current height and speed of the desk as it moves.

Remember to ensure that the ports and IPs are configured in both the server and client config.yaml files (or provide them as command line arguments).

You can start the server like this:

linak-controller --server

And then on the same or different device:

linak-controller --forward --move-to 800

You can also use any of the favourites that are configured on the server:

linak-controller --forward --move-to stand

You can also directly post a JSON object to the server:

curl -X POST http://127.0.0.1:9123 --data '{"command": "move_to", "move_to": 640}'

There is also a simpler TCP server mode which you can with:

linak-controller --tcp-server

And then use any tool you like to send commands. For example you could use nc on linux:

echo '{"command": "move_to", "move_to": 640}' | nc -w 1 127.0.0.1 9123

If you use the linak-controller command to send commands to the server then you will receive live logging back from the server, which you will not receive if you post JSON or use the TCP server.

Troubleshooting

Connection failed

The initial connection can fail for a variety of reasons, here are some things to try if it happens repeatedly:

• Try ensuring that the desk is paired but not connected before using the script.
• Try increasing the scan-timeout and connection-timeout.

Connection / commands are slow

• Try reducing the connection-timeout. I have found that it can work well set to just 1 second. You may find that a low connection timeout results in failed connections sometimes though.
• Use the server mode. Run the script once with --server which will start a persistent server and maintain a connection to the desk. Then when sending commands (like --move-to sit or --move-to 800) just add the additional argument --forward to forward the command to the server. The server should already have a connection so the desk should respond much quicker.

Error message "abort" on MacOS

On MacOS the process may quit with a vague message like abort. This could be because the application running the process doesn't have access to Bluetooth. To provide access, open System Preferences -> Security & Privacy -> Privacy -> Bluetooth and drag the application running the process into the list (eg. Terminal or iTerm2). More info at the bleak issue

Scanning and connection issues on MacOS 12 (Monterey)

There was a bug with MacOS 12 that prevents connecting to bluetooth devices with this script see this issue or this bleak issue for more info.

You should update to MacOS 12.3 which fixes this issue.

Desk movement stuttering

Try lowering the move_command_period config value.

Recipes

There is a page with a few examples of different ways to use the script: RECIPES

Development

Install the dependencies with poetry:

poetry install

Then you can run the script with:

poetry run python -m linak_controller.main <command>

You can also install the project in editable/development mode with:

pip install -e .

To build the project for publishing run:

./scripts/build

And to publish the project to PyPi run:

./scripts/publish

Projects using this project

Other useful projects that make use of this one:

• Home Assistant Integration by @j5lien

Attribution

Some ideas stolen from:

• idasen-controller by @pfilipp for working out the functionality of the REFERENCE_INPUT characteristic which allows more accurate movement.
• linak_bt_desk by @anetczuk (forked from @zewelor) for general information (particularly the initialisation though)