Hi friends.
I am looking for a ESPHome solution that scans the gate area before it allows the gate to close; particularly the gate clearance area. I used to have an inbuilt IR sensor but that has stopped working… My research seems to suggest maybe an ultrasonic sensor would work… but I am not sure how to implement it. any suggestions? It is unlikely i have power there… unless i draw from the gate… so prefer a battery powered solution, thanks v much in advance community 
Esp battery powered is quite challenging if it needs to be responsive (not in sleep 99% of time).
And how would it command the gate if it’s not wired?
What you mean with inbuild? Normally gates use separate ir-beam brake sensors.
Yeah I would have thought a break-beam solution using power from the gate would be the way to go.
Battery powered would definitely be more of a hassle.
But I guess other beam bouncing solutions might do the job too if you get the right sensor that can get the distance and field of view right.
Will you get wifi out there?
Won’t the sensor need to interface/interlock with the gate? So might as well share power?
I’m sure I’ve seen a fair few other similar projects on the forum to this.
What’s wrong with gate power supply? I use it without problems for my esp32 which controls gate, electronics has more than enough reserve for that. You just need to convert it’s 24VAC to 5VDC. If you use switcher for that draw from 24VAC will be even smaller. I use graetz and module similar to THIS - it’s just an example, make sure it can handle input voltage of about 35V or more.
Regarding sensor: perhaps you should look LD2450, which is, as i read presence sensor with multiple targets options (it can report multiple persons). The topic about it exists here on this forum.