Light sensor
Vacation time was coming up and we needed a way to open and close the chicken coop. This project design began as an analog system with an automotive power window motor control (H-Bridge) and a couple of alarm door switches. However, the switches were of the normally open (NO) type. I needed normally closed (NC). We decided that rather than ordering NC switches it’d be “easier” to use an ESP8266 to control a relay module and provide real time status via wifi. An RTC module rounded out the hardware. This was a rather large shift from the original design … cool.
Cordless screwdriver
I had acquired a Black&Decker rechargeable screwdriver from a thrift store sometime in the past and this became the basis of our motor. It has a docking station which made it convenient for mounting. For the brains of the operation I used a NODEMCU 0.9 that I had laying around. I found two alarm reed NO switches that would make the limit sensors. A photocell for daylight detection and a surplus power brick that has 12VDC & 5VDC outputs. Some 2×4 lumber and a small piece of plywood for the door. A short amount of kite string is used to lift and lower the door.
I cut the the plywood into a 12″ x 18″ door. The 2×4 was cut into a frame with a notch to allow the door to slide up and down. The notch was cut using a router with a 3/4″ bit. A 1″ hole was drilled on the top of the frame to allow the string to freely move the door up and down.
I found an existing Arduino program on github that looked like I could use as a starting point. After a number of changes I was able to get a functioning unit. We installed it into the chicken coop and after a few days of beta testing we opened the hole and went live with it. The chickens took to it right away.
For my software I chose to use the ESP8266 instead of the ESPDUINO board, add a motor run timeout, & door sensor validation. Version 2 will have OTA updates and an LCD display.
