ESP32-CAM Wildlife Camera Trap with Night Vision

Ecologists and forest departments need to know which animals use a trail and when, but sitting in a hide for nights on end does not scale — and camera traps sold commercially cost far more than a student budget allows. The DIY answer is a motion-triggered camera: a passive-infrared sensor detects the warm body of a passing animal and fires a camera in a fraction of a second, day or night. This project builds exactly that around the ESP32-CAM: an HC-SR501 PIR module wakes the controller from deep sleep, the camera captures a frame lit by an 850 nm infrared LED ring that animals cannot see, and the image is written to microSD with a date-time stamp from the firmware clock. The demo triggers on hand waves in the lab and shows the captured frames, the IR illumination in a darkened room, and the deep-sleep current that makes field deployment plausible. It is a neat package of embedded skills: interrupt-driven wake, camera pipelines, invisible illumination and power budgeting.

1. The unit is armed and the ESP32 enters deep sleep; only the PIR sensor stays powered, watching its detection cone.
2. A warm moving body crosses the PIR field; the sensor drives its output high, firing a wake interrupt on the ESP32.
3. The firmware boots the camera, checks ambient light, and enables the IR LED ring if it is dark.
4. The OV2640 captures a still frame, which is encoded to JPEG at the configured quality setting.
5. The image is written to the microSD card with a timestamped filename, and an optional second frame follows after a short delay.
6. The ESP32 returns to deep sleep, ready for the next trigger, drawing only the sleep current until then.

Tech stack:

• ESP32-CAM module (OV2640 camera)
• HC-SR501 PIR motion sensor
• 850 nm IR LED illuminator ring
• MicroSD card storage
• Battery pack with deep-sleep design
• LDR for day/night detection
• Arduino IDE (C/C++ firmware)
• Weatherproof housing guidance (buyer-fitted)

• [PIR motion trigger] The HC-SR501 passive-infrared sensor detects warm-body movement across its field and generates the wake interrupt — no continuous camera polling needed.
• [ESP32-CAM image capture] The OV2640 camera captures still frames on trigger, with configurable resolution and JPEG quality trading detail against SD card space.
• [Infrared night vision] An 850 nm IR LED ring illuminates the scene for night captures; the light is invisible to animals and to human eyes, so behaviour is undisturbed.
• [Timestamped SD storage] Every capture is saved to microSD with date and time in the filename, producing a sortable, reviewable image log of trail activity.
• [Deep-sleep power design] Between triggers the ESP32 sleeps at microamp-level current (design target), waking only on the PIR interrupt — the key technique for unattended field operation.
• [Day/night auto behaviour] A light-dependent check selects normal capture by day and IR-illuminated capture by night, so one deployment covers the full 24-hour cycle.
• [Adjustable PIR sensitivity] On-board potentiometers set detection range and trigger hold time, letting the student tune the trap to the target animal size and trail width.

• Working camera trap prototype (ESP32-CAM, PIR sensor, IR LED ring, SD card, battery pack)
• Complete firmware source code (PIR wake, camera capture, IR control, deep sleep, SD logging)
• PIR tuning guide (sensitivity and hold-time adjustment for different trail setups)
• Power-budget worksheet (sleep vs active current, estimated field life calculation method)
• Circuit and wiring documentation
• Project report PDF (camera-trap background, PIR physics, IR illumination, power analysis)
• PPT presentation for final review
• Viva Q&A preparation document (PIR sensing, camera interfacing, deep sleep, IR vs visible light)
• Setup and demonstration guide

• This is an unattended-field electronics prototype; the weatherproof enclosure, mounting and camouflage are fitted by the buyer following the included guidance.
• The firmware clock timestamps images from the ESP32's internal RTC, which drifts without network sync — for multi-week deployments a DS3231 add-on is documented as an option.
• PIR sensors detect moving warm bodies; a stationary animal or heavy rain/foliage motion can cause missed or false triggers — sensitivity tuning is part of the documented procedure.
• Night range is limited by the IR LED ring's throw (a few metres); this is a trail-closeup trap, not a long-range spotter.
• Battery life is estimated from the power-budget worksheet, not measured across a full deployment — the buyer validates it during their own field test.