The Raspberry Pi imagenode in the barn can monitor outside air temperature and detect motion of critters wandering about. Here is an imagehub log that shows motion detected behind the barn, along with a couple of pictures that were taken when the coyote activated the motion detection.
Here is what the back of the barn looks like with the infrared "PiNoir" style PiCamera, a temperature sensor and the infrared floodlight that lights the seen after dark. First, a view of the full back wall of the barn:
And here is a closer view showing the infrared floodlight, the temperature sensor and the PiNoir infrared style PiCamera:
And, finally, a closeup of just the PiNoir PiCamera and the temperature sensor:
The Raspberry Pi is inside the barn and the PiCamera ribbon cable and the temperature probe cable are passed through holes drilled in the barn wall:
The "PiNoir" PiCamera module is the same as the usual PiCamera module and uses the same ribbon cable to connect to the Raspberry Pi computer. However, the lens has no infrared coating. Quoting from the Adafruit website: "The NoIR Camera has No InfraRed (NoIR) filter on the lens which makes it perfect for doing Infrared photography and taking pictures in low light (twilight) environments." Adafruit sells the PiNoir camera module for $30.
The temperature probe used is a waterproof DS18B20 digital temperature sensor, that is connected to GPIO pin 4 for signal (the other 2 wires are connected to the 3.3v pin and ground). The probe was purchased from Adafruit for $10. Adafruit also has a great tutorial for setting up and reading the probe in Python. You can see the code I used for reading the sensor in the imagenode repository.
The infrared floodlight is not connected to the GPIO pins, because it has its own photocell that turns the floodlight on at night and off in the daytime. I have tried multiple infrared floodlights and spotlights. The one I have had the best results with is an 8W IR floodlight available for $30 on Amazon. It sends out plenty of infrared light so that a PiNoir camera can see raccoons, rabbits and coyotes at night up to 20 feet away. Keep in mind that these 12V lights often come in Floodlight style or Spotlight style. For my uses (tracking critters and lighting areas like the inside of the barn or garage), the Floodlight style has been much better.
The imagenode software that captures images, detects motion and reads the
temperature sensor needs an imagenode.yaml file to specify the camera
parameters and the sensor parameters. Here is the one used for the barn camera:
# Settings file for imagenode.py barn camera
---
node:
name: Barn
print_settings: False
patience: 30
stall_watcher: True
heartbeat: 2
hub_address:
# Edit the line below to point to your Mac that will be the test hub
# H1: tcp://jeff-macbook:5555
# H1: tcp://jeff-thinkpad:5555
H1: tcp://192.168.86.70:5555
cameras:
P1:
resolution: (320, 240)
framerate: 16
vflip: True # change to True or False to suit your RPi PiCamera
exposure_mode: night
detectors:
motion:
ROI: (2,2),(98,98)
draw_roi: ((255,0,0),1)
send_frames: detected event # continuous or none or detected event
send_count: 4
delta_threshold: 3
min_motion_frames: 2
min_still_frames: 5
min_area: 2 # minimum area of motion as percent of ROI
blur_kernel_size: 15 # Guassian Blur kernel size
send_test_images: False
sensors:
T1:
name: Temp
type: DS18B20
gpio: 4
read_interval_minutes: 15 # read sensor every X minutes
min_difference: 1 # send if this much change in degreesFor more details about the settings in the imagenode.yaml file or the code to read the temperature sensor, see the imagenode project documentation.