Sensor for altitude: acting on changes along the Y axis?


I’m looking for a sensor that measures either altitude or how heigh it has been moved.

Can any sensor relay this information to ST so I can make an automation trigger when the sensor is above a certain height?

This is a measurement of movement along the Y axis. (Similar to the way fall detection works except of course, that’s moving quickly downwards.) I’m not sure exactly which ones expose this information to smartthings in the new architecture, though. :thinking:

What are the specific details of the use case? There may also be some other ways of doing this.

edited to update because I was wrong about the original device class for these. My thanks to everyone who posted corrections.

Thanks for your reply.

Do you have an example af a accelerometer sensor?

I have two points and I need to know if they have moved further apart og closer together along the vertical axis.

I’m not sure what works now under the new architecture. Hopefully someone else will know. :thinking:

@ogiewon @Automated_House

The attributes for the x,y,z axis are not exposed to make automation conditions in the capability presentation.
Only the accelerationSensor capability is available, which is activated when a value of 1 is received in the acceleration attribute

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Disappointing, but of course I believe you.

I imagine that it is difficult to make routines to compare a capability ,threeAxis, that has one array attribute of three values, x, y, z.

To facilitate it, it would be necessary to make a capability with three independent attributes, one for each axis or a capability for each axis with an attribute.

The x, y, z measurements of that sensor measure rotation on those axes - pitch, yaw and roll - not distance traveled. That won’t be helpful for OP unless the altitude change can be mechanically translated into rotation. Those sensors work on a garage door because the door rotates to a horizontal orientation as it lifts.

You may be able to rig up multiple contact sensors with a single magnet. If the magnet moves up it trips the higher contact sensor; down trips the lower contact sensor.

Otherwise, you may be able to find an analog distance sensor that will work with the Fibaro Smart Implant. However, I doubt you’ll find a ST driver for the smart implant that’s already written to handle a connected distance sensor, so some coding would be required. You could also go the microcontroller route if you’re really up for building your own but ST integration would definitely be a challenge.

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Just to clarify concepts.

Acceleration sensors (Accelerometers) do not measure rotation or rate of rotation, that would be what a Gyroscope measures.

These are linear accelerometers and they measure linear acceleration along its sensitive axis.

In a garage door, what it measures is the acceleration of local gravity (1g= aprox 9.8 m/s²) in one of the three axes of the sensor.

If you have the (Z) axis pointing to the local vertical when the door is closed, then it will measure 1g x cos 0°= 1g of acceleration, or -1g depending on whether the axis is facing up or down.

The other 2 axes (X, Y) will be at 90° to the local gravity vector and will measure 1g x cos 90° = 0g

When the door opens the acceleration in the Z axis will vary from 1g to 0 g, (1g x cos of the angle of the Z axis with respect to local gravity g)

When the gate is fully open, the Z axis will measure 0g and the X or Y axis will measure 1g or -1g.

The open or closed event will depend on the axis used and the measured acceleration threshold.

The driver outputs closed when the acceleration on the chosen axis is >0.9g
It emits open when it is <0.1g.

I am not a software developer, but I have spent my professional life maintaining Inertial Navigation Systems and Autopilots, based on gyroscopes and accelerometers. :wink:

Therefore this would not serve you at all for your purpose of measuring how move one object has come to another.

For that you would have to find an analog distance sensor, as philh30 said.

You can make one with a sliding, non-rotary and linear potentiometer, not logarithmic like the volume ones and connect it to a fibaro smart implant to one analogic input:

If the potentiometer has 60 mm, 10kohm linear and you feed it with 10 vdc and fixing the cursor to the object you want to control:
1v = 6mm
0.1v= 0.6mm

You have to adjust it to the correct measurements of the cursor offset