A good friend had loaned me his trail camera during the COVID-19 lock down period of eight weeks. We’re still on level four with no end in sight. I returned his camera to him yesterday. I had learnt a lot using it and got some really great footage of animals roaming on my 1.6 hectare RaDAR playground.
In the meantime I’ve been experimenting using a cell phone activated through an infrared movement detector using the principle of a selfie stick. The signalling from the detector isn’t that intelligent though only having a NC (Normally closed) contact. The cell phone requires a decent timed signal.
So I introduced an Arduino NANO into the picture to handle all the critical processing and to make my camera a little more intelligent other than just using an infrared movement detector.
One of my CCTV cameras had failed so I replaced it with a spare I had. I dismantled the old camera removing the video section but keeping it’s infrared nighttime LED’s. I noticed they were controlled internally by a light sensor so that made the complexity of detecting night or day obsolete. I’ll simply turn the LED’s on, on movement detection switched through the Arduino like I do the camera.
Almost all camera apps react to a volume up or down signal and this is the principle on which selfie sticks work. Various resistor values across the mic connection are recognized by the app as commands. A 450 ohm resistor switched across the mic connections will be seen as a “Volume down” event and the camera activated.
Some apps react to short and “long press” events so the Arduino timing becomes critical. Having control of the source code makes that an easy task.
I’m in the process of building the “work in progress” into a heavy duty plastic container which includes a 7 A/Hr SLAB for long term battery supply to power the Arduino, detectors, infrared LED’s and to keep the cell phoned charged too. I intend to use my old Nokia 3 whose screen was cracked after a fall. The camera is still perfect!
Once everything is working and nicely tested I may paint it using camo colours. It’s simply a box you can place in the field somewhere strategic and enjoy looking at captured photos later.
It can even be used to capture trail runners as they pass specific points.
A work in progress – a “lock down” project 🙂
The initial code as a basic starting point ….. (Indentation removed by the WordPress editor)
// Intelligent cell camera
// by Eddie Leighton
// 20th May 2020
// ————————————-
int PIRSensor = 12; // NC Signal from PIR Sensor
int CAMERATrigger = 13; // Signal to relay board to trigger camera
int sense; // PIR Sensor sense variable
// ————————————-
void setup() {
//Serial.begin(9600);
pinMode(PIRSensor, INPUT);
pinMode(CAMERATrigger, OUTPUT);
//Serial.println(“Cell camera interface inititalised”);
digitalWrite(CAMERATrigger, HIGH); // Initialise trigger relay
}
// ————————————-
void triggerCAMERA() {
//Serial.println(“Camera has been triggered”);
digitalWrite(CAMERATrigger, LOW);
delay(500); // 470 ohm from ground to mic for 500 milliseconds
digitalWrite(CAMERATrigger, HIGH);
}
// ————————————-
void loop() {
sense = digitalRead(PIRSensor); // Test for PIR Sensor movement detection
if (sense == HIGH) {
triggerCAMERA();
}
delay(2000); // Allow two seconds for PIR reset
}
73 de Eddie ZS6BNE
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