IRForum

What do you recommend for a beam break (light barrier) across a 4.5m wide driveway?

It looks like I need a TSAL6100 as an emitter in either the SendIR or DIY IR and the receiver would be either DetectIR or A.IR Shield Rx.
Are there any considerations if this was to be solar powered? Such as to reduce power usage.
I was thinking of controlling the emitter with this, https://www.adafruit.com/product/3500. Programmed with the Arduino IDE. It runs at 3.3V and has two high speed PWM outputs.
I was looking at this for the receiver, https://wisen.com.au/store/products/whisper-node-lora/. It's a 3.3V Arduino clone using the ATMega328p.

Another aspect I had thought of was to use two beams separated from each other so that the direction of the passing vehicle could be calculated and false alarms reduced. But, since these beams have some spread to them I can see problems with overlap unless emitters and receivers are separated and emitters rotated away from each other. See attached sketch.

Here's a project I stumbled across that got me looking at using a TSAL6100: https://blog.voneicken.com/2018/light-barrier/

Thanks,
Robin

Lots of approaches possible:

- Off the shelf - look at Aliexpress and search for "beam infrared". Many low cost solutions with enclosures you could use.
- As its only 4.5m....also consider PIR detectors or Ultrasound or even 'pseudo radar' modules

For a more DIY approach:
-TSAL6100 is a good choice.
- We also have a solution for beam/barrier called BeamIR see: https://www.analysir.com/blog/2015/09/2 ... t-barrier/ (In stock, but not currently listed in our shop)
The Tx module generate the IR signal without needing any MCU..so is essentially standalone. The Rx module has open collector & TTL output available.

It looks like I need a TSAL6100 as an emitter in either the SendIR or DIY IR and the receiver would be either DetectIR or A.IR Shield Rx.

Yes any of the above. Also our A.IR Shield Nano could be used to integrate the RF as well.

Are there any considerations if this was to be solar powered? Such as to reduce power usage.

Very much so. Use 33% duty cycle for the IR carrier. Make sure that any IR receiver is looking away from the Sun - where possible. It will be a trade off between current draw & resilience to interference,

I was thinking of controlling the emitter with this, https://www.adafruit.com/product/3500. Programmed with the Arduino IDE. It runs at 3.3V and has two high speed PWM outputs.

As above our BeamIR module generates the IR signal without any MCU required.

I was looking at this for the receiver, https://wisen.com.au/store/products/whisper-node-lora/. It's a 3.3V Arduino clone using the ATMega328p.

Lots of alternatives available & depends on your location & distance from the server

Another aspect I had thought of was to use two beams separated from each other so that the direction of the passing vehicle could be calculated and false alarms reduced.

You can achieve all this by adding mirrors (or similar reflector), plus you can have the Tx & Rx on the same side!

Solar: You may have to consider a lot here:
- with an always on beam @100ma peak & 33% duty cycle => 33mA draw. Typically for a powered connection.
- as in the article you linked....using a pulsed beam will reduce the avg current & interference. He uses 50%...but 33% duty cycle is OK
- having Tx & Rx on the same side of the driveway - greatly reduces complexity & power management.
- Probably a good idea to over-spec the panel & battery a bit if going the solar route - to avoid maintenance.

ETC.
Using ~5mm tubes can improve the targeting of the beam for both Tx & Rx. The 'Pro' approach would be to used focused optics.
If the Driveway is right beside the house(?)...you could potentially run it all from the house using mirrors/reflectors. (Or the 'radar' style solutions)
Tree & bushes can introduce interference, particularly when wet....if the beam is not focused/directional.

Thank you for your reply and great advice.
It's good that I don't needs a MCU for the emitter portion.
Luckily, my first attempt at this will be near the house and I won't need the solar option. However, the terrain and foliage is too complex for a mirror reflector setup directly from the house. I will give that option some more thought though for another location.
My sensors would need to be 5.5m apart but from the spec sheet that distance isn't a problem.
How much does the BeamIR set cost?

Thanks,
Robin

How much does the BeamIR set cost?

US$12.50 for Tx or Rx module individually or $20 for a pair. Plus $5.75 worldwide shipping.

They are 25x25mm each.

The Tx module also has dual IR Emitters (One can be disabled via jumper if required). (There is also a power selector jumper with 3 level settings).

The carrier is crystal controlled for higher stability (vs 555 or internal oscillators of MCUs) = better performance with changing temperatures.

If needed, you can tap into the IR carrier signal as well via spare outputs on the Header. (e.g. You could drive a SendIR module from this)

The Rx module had LED indicator and both Open collector output and a voltage level output. So you could drive a load(buzzer, light indicator or relay or input directly into an MCU). Extra precautions are required for driving relays & heavy loads.

If interested, you can order via https://www.analysir.com/blog/product/g ... ent-in-us/
Just enter the quantity to match the total $ amount and leave a note.