Possible repurpose to a vehicle presence sensor

[Michael McSharry]

I would be happy with a CheaperRFID to MQTT plugin resembling your old xAP Cheaper RFID plugin. Thinking I wrote about this a while ago.

The subject has come up a few times such as How do RFID tags work with Homeseer? - HomeSeer Message Board

It is also possible to use mcsMQTT. It has a Serial capability for which you select the port if local or IP if remote and SPACE as the delimiter. The data received is a unique four character code such as " ABCD" or ""BB7F". I provided a walkthrough of doing this at Cheaper RFID with mcsMQTT - HomeSeer Message Board

[Wade]

Amazon.com: USB Garage Door Opener + 2 USB for Car Garage Door Opener Automatic Door Opening,Home Access Control Opener System Receiver with USB Door Opening Device,2.4G Bluetooth Connection (2) : Electronics


There is no way I would hook this to my garage door system, but...

The car portion of the instrument us a USB / Bluetooth dongle.
The home portion is the receiver.
Supposedly, when the Bluetooth dongle comes within 30 ft of the receiver, one set of the dry contacts will pulse.
Also supposedly, when the Bluetooth dongle leaves range of the receiver, another set of the dry contacts will pulse.
Use your favorite dry contact input system for your HS system.

If the USB port in the car powers off when you turn off your car, the receiver will think you car has left.
Either leave the USB dongle in a constantly powered car USB port, or if your USB port shuts off when the car is shut off, you will get arrival only signals.

'1st channel connect will door OPEN, 2nd channel connect will door CLOSE.'

At $9.99 per set, I am in for three. Unfortunately, I won't be hands on for over a week.

Cheers, Bill

Received one of these yesterday. It wasn't entirely clear to me how the Ch1 and Ch2 worked from the product description so I did some bench testing. Bill was correct in his explanation above.

BASIC OPERATION
As advertised, the dongle that came with the base unit was already paired and worked without any configuration. When the BT signal comes in range, the Ch1 contacts close for a fraction of a second. A blue LED on the board (not directly exposed to the outside but visible through openings in the case) comes on. The blue LED remains on while the dongle is in range. When the dongle is out of range (powered down in my testing), there is no immediate response at the base unit. After the dongle has been out of range for ~10 seconds, the Ch2 contacts close for a fraction of a second and the blue LED turns off.

If the dongle goes out of range but comes back into range within 10 seconds, the Ch1 contacts cycle but the Ch2 contacts do not cycle at the end of the original 10 seconds. This could be a useful delay to help filter brief signal drops if using the device for vehicle presence.

ADDITIONAL BT DONGLES
I ordered a pack of 2 extra dongles. I verified that those dongles did not activate the contact closures prior to pairing. Pairing another dongle was simple after which both dongles activated the contacts in the same manner.

If one dongle is in range (LED is on) and the second comes in range, the Ch1 contacts are cycled. If both dongles are in range and one leaves range, nothing happens. I.e., no cycling of Ch2 after 10 seconds if one dongle is still in range. I did not test with more than 2 dongles but would expect similar results.

THOUGHTS
The device appears to have promise for vehicle presence. It seems to me a separate base/dongle pair will be required for each vehicle for discrete tracking. Each base device will in turn need two sensors for interface with HS. This could be z-wave devices such as door sensors with external inputs, sonoff, Shelly, etc. I would like to hear what device(s) others end up going with. I suspect a sonoff flashed with Tasmota will be how I go since I have them in my current ecosystem and they're inexpensive.

A consideration discussed earlier in the thread is constant power to the dongle as most vehicles disconnect power to power ports either immediately on turning off the engine or after a fixed time period. Although at least one vehicle I've owned in the past few years had one port that remained powered continuously regardless of ignition key position. Now to figure out that and the HS integration...





The right button on the case doesn't have a corresponding button on the board and therefore doesn't do anything. The working button is for pairing dongles. Individual dongles cannot be deleted as far as I can tell. All paired devices are deleted by holding the button for 5 seconds.

[Bill Brower]

Wade Oh man! Thank you for the comprehensive write-up. Agreed, one set per vehicle.
Thank you again

[Bill Brower]

Wade,
The blue LED remains on while the dongle is in range. <--- Very helpful
I am now considering pulling that LED and swapping in an optocoupler. One less input per vehicle and simplified logic within HS events and device.

Additionally, I may set up an HS event to text me in the event the vehicle has left and the garage remains open after xx minutes.

wrb

[Wade]

I am now considering pulling that LED and swapping in an optocoupler.

Bill, I'd like to know more about this. I understand the concept, but would you mind talking through the steps of making it happen? Not sure I'm up to the tiny soldering work but might give it a try given how inexpensive these are.

[Pete]

Here device / USB pair got damaged during shipping and was refunded for my order from Amazon. Went back to Amazon and new deal is one USB dongle and device which I may order in the next couple of days.

For 5VDC here in the automobile went to autonomous wired micro 12VDC to 5VDC devices rather than using my 12VDC. Rewired the power using Fuse taps depending on whether it is 12VDC constant or ignition on 12VDC.

It looks much like an ESP dual relay switch and the JTAG ports are their for upgrading the firmware to Tasmota. Historically here have not used BT for automation. That is me though.

[McQueeSteveul]

'1st channel connect will door OPEN, 2nd channel connect will door CLOSE.'
Sports devil

[Bill Brower]

Bill, I'd like to know more about this. I understand the concept, but would you mind talking through the steps of making it happen? Not sure I'm up to the tiny soldering work but might give it a try given how inexpensive these are.

I have opted to go another direction. I will still use the LED as the primary indicator, but I found these on Amazon:
Songhe LM393 Light Detection Optical Sensitive Resistance Sensor Module Photosensitive Sensor for Arduino 3 pin (10PCS): Amazon.com: Industrial & Scientific

They have analog and digital outputs, have adjustable sensitivity and are 3.3 or 5.0 V compatible.

[Wade]

I have opted to go another direction. I will still use the LED as the primary indicator, but I found these on Amazon:
Songhe LM393 Light Detection Optical Sensitive Resistance Sensor Module Photosensitive Sensor for Arduino 3 pin (10PCS): Amazon.com: Industrial & Scientific

They have analog and digital outputs, have adjustable sensitivity and are 3.3 or 5.0 V compatible.

Also a nice solution, and the price is right.

I notice the one at the amazon link appears to only have digital output based on the description and images, although versions both with and without analog output are shown on the schematic.

[Bill Brower]

I may have mixed up the image. I really only wanted the DO anyway. Later

[Bill Brower]

Success. I have the light detector board mounted On the Bluetooth receiver board with the photo receiver directly above blue dongle present LED. That blue receiver LED stays on while the dongle is in range. The light detector pulls the DI low. I'll have ESP relay that info to HS.

[Michael McSharry]

A technique I have used in the past with a driveway alarm is to connect the alarm’s DO to a QUICHIP that produces a RF code. These chips are used in the 4-button RF fobs. The Sonoff RF bridge or SDR will recognize the code and forward via Ethernet the event notification. mcsMQTT.pdf describes the QIACHIP. It is a very cheap way to provide notifications without needing to deal with wires. One QIACHIP has four inputs so can handle the two relays with a single device. In mcsMQTT this can be represented as a single input with two states via VSP association or as two separate devices in HS.

[Bill Brower]

Michael McSharry Nice. I really dig ESP based microcontrollers running ESP Easy. From there I can split the signals to my Hubitat, HS4, anywhere that takes MQTT, and Pushover via HTTP. I’ll have HS4 connection alive LED indicators and an LCD display, just because I can.

[AshaiRey]

I have opted to go another direction. I will still use the LED as the primary indicator, but I found these on Amazon:
Songhe LM393 Light Detection Optical Sensitive Resistance Sensor Module Photosensitive Sensor for Arduino 3 pin (10PCS): Amazon.com: Industrial & Scientific

They have analog and digital outputs, have adjustable sensitivity and are 3.3 or 5.0 V compatible.

Since this is the 'cool automations' thread here's a tip.
These cheap sensor modules can easily be used for other things by replacing the LDR for something like a NTC resistor. When doing that it will reract on a preset temperature. Detecting a soundlevel is also possible according me. They are also used as soil sensors. Many more things to think about.

[jon00]

Looks like the USB Bluetooth devices average around 1 milliampere (5V).

Just an idea, if you don't want to mess with your car's electrics to get a permanent 24/7 feed, I expect you could use a USB power bank for this.

A cheap 5000 mAh version would last for weeks without charge. Keeping this plugged in to your cars supply would charge it whenever the vehicle was used.