What is LoopString?
LoopString is a cloud-connected IoT automation platform that lets you monitor and control edge devices from a web dashboard. Design custom control systems visually, deploy them to Raspberry Pi hardware, and track everything in real time.
How It Works
LoopString connects three layers:
- Edge Devices — Raspberry Pi units running Node-RED handle sensor reading, actuator control, and PID loops locally
- Cloud Backbone — Firebase provides real-time data sync, user authentication, and historical storage
- Web Dashboard — A React application for monitoring, configuration, and control
Data flows in one direction for safety: sensors publish readings through Node-RED to Firebase Realtime Database, and the dashboard subscribes to those updates. Commands flow in reverse — the dashboard writes to Firebase, and Node-RED on the Pi picks up the command.
Key Components
Dashboard
Your central control panel. View live sensor readings, toggle actuators, adjust PID setpoints, configure alarms, and review analytics — all from your browser or mobile device.
Configurator
A visual drag-and-drop editor for designing automation flows. Select sensors, actuators, and controllers from the parts library, wire them together, and deploy directly to your Pi.
Parts Library
A catalog of supported hardware — temperature sensors, relays, motor controllers, Sequent Microsystems HATs, and more. Each part comes with pre-built Node-RED templates.
Node-RED Engine
Runs on the Raspberry Pi to execute your automation flows. Handles real-time sensor polling, PID control loops, actuator commands, and data publishing to the cloud.
Supported Hardware
- Raspberry Pi — Primary edge compute platform (Pi 3B+, Pi 4, Pi 5)
- Sensors — DS18B20 (temperature), BME280 (temp/humidity/pressure), MH-Z19 (CO2), Atlas Scientific EZO (pH, EC, DO), analog sensors via ADC
- Actuators — GPIO relays, PWM outputs, Sequent Microsystems relay/MOSFET HATs
- Protocol Bridges — MQTT, Modbus RTU/TCP, S7comm for industrial PLCs
- Additional Platforms — Arduino, ESP32, and PLC devices via Pi gateway
What You Can Build
- Environmental monitoring — Track temperature, humidity, CO2, and air quality
- Grow room automation — Control lights, fans, heaters, and irrigation on schedules or PID loops
- Aquaponics and hydroponics — Monitor pH, EC, dissolved oxygen with closed-loop control
- Home automation — Smart relay control with scheduling and remote access
- Industrial monitoring — Connect PLCs and industrial sensors via Modbus or S7comm
Next Steps
- Creating an Account to get started
- Adding Your First Device to connect a Raspberry Pi
- Configurator Overview to design your first automation flow