How to Use DFRobot C4001 mmWave Presence Sensor 25m: Examples, Pinouts, and Specs

The DFRobot C4001 mmWave Presence Sensor 25m is a high-precision sensor designed to detect the presence of objects or people using millimeter-wave (mmWave) technology. With a detection range of up to 25 meters, this sensor is ideal for applications requiring accurate and reliable presence detection. Its compact design and robust performance make it suitable for use in security systems, smart home automation, industrial monitoring, and more.

• Security systems for motion and presence detection
• Smart home automation (e.g., lighting and HVAC control)
• Industrial monitoring and safety systems
• Retail and public space occupancy monitoring
• Robotics and autonomous systems

The following table outlines the key technical specifications of the DFRobot C4001 mmWave Presence Sensor 25m:

The DFRobot C4001 sensor has a 4-pin interface. The pin configuration is as follows:

To use the DFRobot C4001 mmWave Presence Sensor, follow these steps:

1. Power the Sensor: Connect the VCC pin to a 5V DC power source and the GND pin to ground.
2. Establish Communication: Connect the TX pin of the sensor to the RX pin of your microcontroller (e.g., Arduino UNO) and the RX pin of the sensor to the TX pin of the microcontroller.
3. Configure the UART Interface: Set the UART baud rate to 115200 bps for communication with the sensor.

Below is an example of how to interface the DFRobot C4001 sensor with an Arduino UNO:

// Include necessary libraries
#include <SoftwareSerial.h>

// Define the RX and TX pins for SoftwareSerial
SoftwareSerial mmWaveSerial(2, 3); // RX = Pin 2, TX = Pin 3

void setup() {
  // Initialize serial communication
  Serial.begin(9600); // For debugging via Serial Monitor
  mmWaveSerial.begin(115200); // Communication with the sensor

  Serial.println("DFRobot C4001 mmWave Sensor Initialized");
}

void loop() {
  // Check if data is available from the sensor
  if (mmWaveSerial.available()) {
    String sensorData = mmWaveSerial.readString(); // Read sensor data
    Serial.println("Sensor Data: " + sensorData); // Print data to Serial Monitor
  }

  delay(100); // Small delay to avoid flooding the Serial Monitor
}

• Ensure the sensor is mounted in a location free from obstructions for optimal performance.
• Avoid placing the sensor near strong electromagnetic interference (EMI) sources.
• The sensor operates at 3.3V TTL levels for UART communication. Use a level shifter if interfacing with 5V logic devices.
• The detection range and accuracy may vary depending on environmental conditions such as temperature, humidity, and the presence of reflective surfaces.

1. No Data Received from the Sensor

   • Ensure the sensor is powered correctly (5V DC to VCC and GND connected).
   • Verify the UART connections (TX to RX and RX to TX).
   • Check that the UART baud rate is set to 115200 bps.

2. Inconsistent or Erratic Readings

   • Ensure the sensor is not obstructed by objects or placed near reflective surfaces.
   • Verify that the sensor is operating within the specified temperature range (-40°C to 85°C).
   • Check for sources of electromagnetic interference (EMI) near the sensor.

3. Sensor Not Detected by Microcontroller

   • Confirm that the microcontroller's UART pins are functioning correctly.
   • If using an Arduino UNO, ensure the SoftwareSerial library is properly configured.

Q: Can the sensor detect multiple objects simultaneously?
A: The DFRobot C4001 is optimized for presence detection and may not distinguish between multiple objects. For advanced object tracking, additional processing may be required.

Q: Is the sensor waterproof?
A: No, the sensor is not waterproof. It should be used in environments free from moisture or enclosed in a protective housing.

Q: Can the sensor be used outdoors?
A: Yes, the sensor can operate outdoors, but it should be protected from direct exposure to rain or extreme environmental conditions.

Q: What is the maximum detection angle?
A: The sensor has a horizontal detection angle of 120° and a vertical detection angle of 30°.

By following this documentation, users can effectively integrate the DFRobot C4001 mmWave Presence Sensor 25m into their projects for reliable and accurate presence detection.