DIY Handbrake for under 25 bucks

[Mr. Vermeer]

I made my own handbrake (prototype) for a fraction of the cost that retailers dare to ask.

It's based on an aluminium hydraulic handbrake from China and uses a Hall-Sensor and a neodymium magnet to detect the motion of the handle. The Hall-Sensor is wired to a Pro Micro (Arduino) board which is used to connect to a PC. A microphone stand clamp is used to clamp the handbrake to my desk.

I made a very short video demonstrating the features of this prototype:

It's still a prototype and needs some improvements. For instance, the Hall-Sensor is only digital and simply outputs LOW or HIGH when in a certain proximity of a magnet. To create an analog handbrake, you would need a ratiometric Hall-Sensor that outputs the strength of the magnetic field as value between 0 and 5V.
Due to the design of the handbrake, the pivot point is not ideal for my setup and I had to improperly mount the handle. No big deal in this application, but it looks sloppy.
The spring I added was an old G27 gaspedal spring I had laying around. This proved to be too weak so I had to add some rubber bands to tighten it up. Spec'ing a proper spring is costly so if anyone has some suggestions, let me know!

I'll post links to all products used and Arduino code soon.

 

[Mr. Vermeer]

The parts I used are as follows:

- Handbrake:
https://nl.aliexpress.com/item/325630...

- Hall-Sensor:
https://nl.aliexpress.com/item/326539...

- Pro Micro:
https://nl.aliexpress.com/item/327752...

- Clamp:
https://www.thomann.de/nl/gravity_mst...

- Arduino Code:
https://drive.google.com/file/d/1YoXz...

 

[Mr. Vermeer]

UPDATE!

I sourced a better clamp:

It's a bit sturdier in vertical motions and slightly better at handling side to side motion. It's also easier to mount as you can use the predrilled holes of the plate that comes with the handbrake.

Link to where I bought this clamp is in video description.

 

[MoodyB]

You could also use a single monitor mount (£15 here in the UK) fitted upside down, with the handbrake bolted to the vesa plate.
This would give you height adjustment if you wanted it lower.

 

[Mr. Vermeer]

You could also use a single monitor mount (£15 here in the UK) fitted upside down, with the handbrake bolted to the vesa plate.
This would give you height adjustment if you wanted it lower.

Sorry for the late reply, but I imagine that wouldn't be sturdy enough. I've replaced the spring to a stiffer one and I have trouble clamping it down solidly enough. Maybe a monitor stand would work, but there has to be little flex in the stand itself.

 

[Mr. Vermeer]

UPDATE 2

Made the handbrake response analog and upgraded the spring to a stiffer one.

 

[stefbox99]

Did you update the code?

 

[jookie]

Arduino: 1.8.10 (Windows 10), Board: "Arduino Leonardo"

Sketch uses 7712 bytes (26%) of program storage space. Maximum is 28672 bytes.
Global variables use 280 bytes (10%) of dynamic memory, leaving 2280 bytes for local variables. Maximum is 2560 bytes.
processing.app.debug.RunnerException
at cc.arduino.packages.uploaders.SerialUploader.uploadUsingPreferences(SerialUploader.java:152)
at cc.arduino.UploaderUtils.upload(UploaderUtils.java:77)
at processing.app.SketchController.upload(SketchController.java:732)
at processing.app.SketchController.exportApplet(SketchController.java:703)
at processing.app.Editor$UploadHandler.run(Editor.java:2075)
at java.lang.Thread.run(Thread.java:748)
Caused by: processing.app.SerialException: Error touching serial port 'COM4'.
at processing.app.Serial.touchForCDCReset(Serial.java:107)
at cc.arduino.packages.uploaders.SerialUploader.uploadUsingPreferences(SerialUploader.java:136)
... 5 more
Caused by: jssc.SerialPortException: Port name - COM4; Method name - openPort(); Exception type - Port not found.
at jssc.SerialPort.openPort(SerialPort.java:167)
at processing.app.Serial.touchForCDCReset(Serial.java:101)
... 6 more
An error occurred while uploading the sketch
Invalid library found in C:\Program Files (x86)\Arduino\libraries\Processing: no headers files (.h) found in C:\Program Files (x86)\Arduino\libraries\Processing
Invalid library found in C:\Program Files (x86)\Arduino\libraries\Processing: no headers files (.h) found in C:\Program Files (x86)\Arduino\libraries\Processing
Invalid library found in C:\Users\jack\Documents\Arduino\libraries\Processing: no headers files (.h) found in C:\Users\jack\Documents\Arduino\libraries\Processing
Invalid library found in C:\Users\jack\Documents\Arduino\libraries\Processing: no headers files (.h) found in C:\Users\jack\Documents\Arduino\libraries\Processing
Exception in thread "Thread-21" java.util.ConcurrentModificationException
at java.util.LinkedList$LLSpliterator.forEachRemaining(LinkedList.java:1239)
at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481)
at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471)
at java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:151)
at java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:174)
at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
at java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:418)
at cc.arduino.contributions.libraries.LibrariesIndexer.rescanLibraries(LibrariesIndexer.java:167)
at cc.arduino.contributions.libraries.LibrariesIndexer.setLibrariesFolders(LibrariesIndexer.java:120)
at processing.app.BaseNoGui.onBoardOrPortChange(BaseNoGui.java:677)
at processing.app.Base.onBoardOrPortChange(Base.java:1333)
at processing.app.Editor$UploadHandler.run(Editor.java:2111)
at java.lang.Thread.run(Thread.java:748)
Invalid library found in C:\Program Files (x86)\Arduino\libraries\Processing: no headers files (.h) found in C:\Program Files (x86)\Arduino\libraries\Processing
Invalid library found in C:\Users\jack\Documents\Arduino\libraries\Processing: no headers files (.h) found in C:\Users\jack\Documents\Arduino\libraries\Processing

This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.

 

[Spyrious]

Hello.I will attempt to build this myself.I tried previously with a slider resistor,that didnt work well.Does the code work on arduino leonardo ?Thanks

 

[Jackpack]

Hello everyone, I have a problem that you will still know how to solve ... I have a very similar handbrake ... but I am not able to improve the detection of the signal before. I put a photo of when the signal detects me.
. Thanks to all