Using ALS to automatically dim light

[totti93 (Lora Gracewood)]

Hi,

I am working on a school project where we are trying to test if it’s possible to use the ALS in smartphones to automatically dim lights through e.g. a ZigBee connection - would any of you happen to have any experience with this or can see it work?? (btw. I’m not an expert in lighting!) Really appreciated your help!

Best regards,

[rpwong (Russ)]

Hi Lora,

I’m not sure what you mean by “the ALS in smartphones”. Does that mean the ambient light sensor?

If so, then yes it’s possible, but with openHAB it would be in a roundabout way.

1. An app called HabPanelViewer would have to be installed on an Android phone to get data from the light sensor. You can’t download this app from Google Play Store or install it on an iPhone.
2. HabPanelViewer would send the data to an openHAB server.
3. If the value drops below a certain level you set, then a rule would trigger to dim the lights
4. The rule would send a command through a ZigBee USB stick to your ZigBee lightbulb/switch.

So as you can see, you’d need a lot of hardware to make it work, and would have to spend time setting up the openHAB server.

You’d also have to think about how to program the rule to avoid unwanted behaviour. For example, if you put the phone in your pocket, the light sensor would trigger the rule.

This will work with any lightbulb/switch that openHAB can control, so not just ZigBee devices.

I hope that answers your question!