There are 2 repositories under motion-sensor topic.
:video_camera: Complete HomeKit integration for all UniFi Protect device types with full support for most features including HomeKit Secure Video, and more. https://homebridge.io
Home Assistant Entity and lighting controller for managing devices with timers, scripts, and sun-based time restrictions.
A Kinect motion capture plugin for Blender
С# API for Xiaomi Mi Home devices
Translate ONVIF events (from IP Cameras) to MQTT messages.
Camera & Motion sensor support for Unifi Protect cameras in Homekit via Homebridge
Arduino Driver for TDK InvenSense consumer motion sensor ICM42670P
LED stairs
Build a motion sensing camera using Android Things
ESP8266 based  HomeKit Motion Sensor that works the same as Elgato Eve Motion
A firmware for ESP8266 based devices to be used as Homekit sensors and Thermostats.
ESP8266 Huzzah Deep Sleep Mode PIR Motion Alarm using IFTTT
Digital signal processing (DSP) such as FFT, FIR, time and frequency domain features calculations, on watchOS ⌚️, Swift APIs 🚀
A HomeKit firmware for a motion sensor infrared motion sensor - this an OTA firmware
Control devices smarter: by grouping, including triggers like motion, opening window, etc. and set target devices accordingly
Homebridge plugin for the AlarmDecoder interface for Honeywell and DSC Alarm Systems. Exposes the security system and all zones (via Contact Sensors and Motion Sensors) to Apple's Homekit. Control your alarm through Siri.
Raspberry pi project that controls jack-o-lantern via servo motor and PIR motion sensors
HueSense is a windows application that allows you to monitor all sensors connected to the Hue system
Linux driver for TDK InvenSense automotive IAM-20680 sensors family
ESP8266 Motion Detector to IFTTT
Extensive control of lights based on time of day with mode event in addition to motion, presence, lux, rain, and media player sensors
Arduino Driver for TDK InvenSense consumer motion sensor ICM45686
How to Build a Water-Resistant, Battery-Operated, Low-Power, Motion-Activated, 5 Mega-Pixel WiFi Camera
Reference Driver for TDK InvenSense consumer motion sensor ICM45686
Mobile sensor
Homekit HAP-NodeJS - Integration of HAP-NodeJS with WS2812(NeoPixel) ,DHT11 ,SONOFF, Raspberry Pi Camera
AirClicker is a cross-platform application developed using Kotlin Multiplatform, to control desktop mouse using the motion sensors of mobile devices (Android/iOS).
Occupancy\Motion sensor HLK-LD1115H-24G ESP32 or ESP8266, Arduino, connection to Home Assistant, Human Presence Sensor Radar
Ikea Molgan PIR LED light hack to add wireless Arduino functionality
Detect pulse rate using microsoft kinect
Android simple Sensors HAL for TDK InvenSense motion sensors
Reference Driver for TDK InvenSense consumer motion sensor ICM42670P
Homebridge Plugin HTTP & MQTT. Supports Light Bulb, Switches, Outlets, Fan, Garage Door, Shades / Blinds, Temperature/Humidity, Motion, Contact and Occupancy sensor, Air Quality, Smoke, Carbon Dioxide and Light Sensor.
Software for a smart mirror that informs the user of basic weather, time, and news events, and supports Google Calendar integration.
Arduino project to detect usage of a table football.