Priorities are strange. I have a huge list of projects on Bonesnapper Ridge, but what came up as the highest priority? The gate opener. Yep, even before power. This is the first project that I am going to build and blog about.
This topic is open for discussion. I would love to have your input on this build.
The Problem
During the construction and move-in phase, I have been going to town 2-3 times a day. Every time I leave, I have to stop the vehicle, get out, walk up to the gate, unlock it, open it, futz with making it stay in the right spot with a stick or a rock, walk back to the car, drive 20 feet, get out, go back and move that rock, close the gate, lock it, walk back to the car, get in and go. Then when I get back, I do the same thing in reverse. It's really not a big deal, just annoying to do so many times. And when it starts raining, it's going to be 100x more annoying.
Why build my own?
My uncle owns a large fencing company in the next county over. He has been in business for something like 45 years and has accumulated a large stock of parts. Apparently, some residents and businesses like to upgrade their gate openers regularly, and they just let him take the perfectly good functional parts. He told me that I can come down and search through the stock and pick out what I need. He has tons of actuators and all the parts that go with them to hook up to my gate. Probably even some keypads, though I am not sure if I can use those or not. So, why build my own? I have access to free parts, and not a complete system. So yeah, sounds like fun!
Also, I have been living behind a gate opener system for the last year and a half. It's a pretty pricey system, high-end stuff. And it has almost no features other than open/close, limit, IR sensor, and a lock. As far as programming goes, you can set multiple codes, and that's it. No logging, no alert, and no way to edit or modify a code/user. I managed the system for a bit and was absolutely surprised that there is no interface other than the keypad. I wanted some logging about who was coming in and out and at what times. Now I have the opportunity to build in all of those features. Let's talk about some of the possibilities:
Possible Features
- Web UI for create/modify/delete of codes/users.
- Logging of usages and possibly errors
- Notifications of the gate opening (SMS / Send pic to my phone of who is operating the gate?)
- Wireless Entry (LoRa for long-range open?)
- Isolated solar power for the entire system.
- Wyze camera for semi 2way comms?
- Other two-way communication?
- Keypads on both sides of the gate
- Limit switches for open/closed states
- IR Sensor for safety? (optional...)
I would like to be able to program it remotely, have a date and timestamped access log, and get notifications at the house (or anywhere I am) when the gate is opened. Those would be my main "upgrades" from the typical system (that I have experience with). Wireless entry is also key (see what I did there?) with a long enough range that the gate is already open by the time I get to it so I don't have to slow down or stop.
What will I have to build?
Since I know my Uncle has lots of actuators to pick from, I figure I will have to build everything else. I am hoping that he has Infrared Sensors and a solenoid-type gate latch at least. Those might be difficult to spec for weather resistance. I will need a motor controller, an MCU to control everything, various relays for IR and a latch, Solar power & batteries for the system, code for the MCU, and wireless entry FOB's and a receiver.
One feature that many gate openers have is detecting resistance on the gate and reversing the direction the actuator is running in so you don't squish anyone in the system. I'm not quite sure how to do this, other than the motor controller having some sort of detection of resistance. I know there are some stepper drivers that can do this, but I am not sure what type of motor the actuator will have. Does anyone know how to do this? Otherwise, the gate is two miles out a private road and there is virtually zero foot traffic up here. I *could* just put a sign on the gate that says, "Don't get squished. It will squish you" and be done with it.
Parts
Let's talk parts. The actuator is an unknown, and maybe I will end up with a couple to choose from. That will determine what type of motor controller I will need. Here is a list of potential parts:
- MCU: This could be a WiFi enabled Arduino, or a Raspberry Pi.
- Actuator: I would like to find an "arm" style actuator that attaches to the gate and the post. Usually, these are a ball screw type actuator.
- Motor Controller: I won't know what type of controller I will need until I get the actuator.
- Keypads: These will need to be IP64/IP65 rated.
- Limit Switches: There are plenty of industrial limit switches that are IP rated for outdoor use.
- Solar Power: I will need to build an isolated solar power system to run it 24/7.
- Control Box: Again, an IP-rated box that will house all of the electronics, solar charge controller, and batteries.
- Steel Square Tube: Probably 4" to make the keypad post/housing.
Power
Since I do not have any power here, and the gate is far enough away from the house that it does not make sense to run power out there, I will need to build an isolated solar power system. I think this part will be pretty easy. I will use a couple of small solar panels and an inexpensive solar charge controller to charge some type of batteries. Probably Sealed Lead Acid since they are affordable, but if I can find a suitable LifePo4 alternative that is affordable, I may go that route since they are quite safe.
A Raspberry Pi will take more power to run 24/7 than an Arduino type MCU and that could be a problem. I will have to account for that power draw plus the opening and closing of the gate X number of times on a battery charge. Same accounting will need to be done if I use an Arduino type MCU, but with less power draw throughout the day. If I decide to go Arduino, then I will have a server running at the house to host the access control and Web UI which will use more power overall (since that will have to be *at least* a Raspberry Pi, in addition to the Arduino). So maybe it makes more sense to have a Pi out at the gate that is 100% powered by that isolated system. What do you think? Pi or Arduino?
Existing Gate
Currently, there is quite an average agricultural style gate with an ~8" post in concrete on the hinge side, and a ~4" post in concrete on the latch side. The gate itself is pretty boring, and I fully intend to build my own gate once the shop is done and I have a nice place to weld. My uncle also offered me to look around his "pile of gates" to see if there was something better or build me a custom gate. I've always wanted to build my own gate, so I am leaning towards that, but if he has something good... It's not off the table.
There is not really a great south-facing spot right near the gate for the solar panels, I will have to set them back a good 40-50 feet to be in an area that gets good access to the sun.
Fabrication & Prep
I will have to do some grunt work for this installation. I will need to install a pole for the solar panel mount, which will probably also have the control box mounted to it. Trench from the control box to the first keypad, trench from that keypad to the gate, then to the second keypad. I will also need to fabricate posts of some sort for the keypads. The keypad and solar posts will need to be cemented into the ground. Ill have to run a conduit from each point to carry conductors.
Discussion Time
Well, those are my thoughts going into this project. I would love to hear any suggestions or ideas you may have on this topic. Everything is open for discussion, I know what I need to do, but I have not settled on exactly how to get there. I will be covering the build in the blog, and there will be an Element14 Presents Friday episode of the build!
I will give an update once I go sort through the parts at my Uncles shop. Hopefully by next week. Meanwhile, I will keep an eye on this post for any ideas or suggestions that come up
-Kaleb
Top Comments