Fall Detection Fails at 45° Wall Mount + Fan Interference (C1001 mmWave)DF Robot

Hi everyone,

I’m working with the DFRobot C1001 mmWave Human Detection Sensor for fall detection using an ESP32, and I’m facing a critical issue when the sensor is mounted at 45° on a wall.

 My Setup

Sensor: C1001 mmWaveMCU: ESP32Mounting:90° (ceiling mount) → partially working with ceiling fan running45° (wall mount, tilted downward) → not workingEnvironment: Indoor room with a ceiling fan

 Problem Description

1. At 45° Mounting:

No fall detection at all (0% success)All tracking values appear almost constant

Example from logs:

TrackX ≈ constant (~70)TrackY ≈ constant (~1036)BodyMove ≈ 1FallState = 0 always

Even during actual movement or simulated falls, values don’t change.

2. At 90° Mounting:

Values are dynamic:TrackY changes significantlyBodyMove increases during motionFall detection works (at least occasionally)

3. Fan Interference Issue

When the ceiling fan is ON:

Sensor sometimes detects false motionBodyMove increases even when no human is presentPossible noise in coordinate tracking

I suspect the radar is picking up fan blade movement (micro-Doppler effect).

Current Configuration

 

hu.dmInstallAngle(0, 0, 0);   // default (for 90°)

 

I tried adjusting for 45°:

 

hu.dmInstallAngle(45, 0, 0);

 

But behavior is still incorrect or inconsistent.

 Observations

At 45°, X/Y coordinates don’t updateLooks like:Coordinate system is not transforming correctlyOr tracking algorithm is failing completelyWith fan ON:Motion detection becomes unreliableHard to distinguish human vs background motion

 Questions

Does this sensor officially support 45° wall mounting, or is it strictly designed for ceiling (90°)?How exactly are TrackX / TrackY coordinates computed when the sensor is tilted?

Is there a correct way to configure:

for wall-mounted (angled) installations?

Why would coordinates freeze completely instead of degrading?Is there any way to filter out periodic motion like ceiling fans?Can sensitivity or thresholds be tuned to reduce fan interference?Is there access to raw radar data for custom processing?

 What I’m Trying to Achieve

Reliable fall detection from wall-mounted sensor (45°)Avoid false triggers due to fanUse X–Y tracking data for better analysis

 Summary

 90° mount → works (expected behavior) 45° mount → tracking freezes, no detection Fan ON → causes false motion signals

 Looking for Help

Recommended mounting configuration?Correct angle calibration?Any firmware limitations or known issues?Best practices for noisy environments (fan, AC, etc.)?

 

Thanks in advance for any guidance or suggestions!