Design and Evaluation of Sensor Housing for Boundary Layer Profiling Using Multirotors

Area of Science:

• Atmospheric Science
• Aerospace Engineering
• Sensor Technology

Background:

• Traditional Unmanned Aerial System (UAS) sensor mounts create turbulent airflow and heat interference, compromising atmospheric data accuracy.
• Descent profiles are particularly unreliable due to sensor exposure to propeller wash and inconsistent aspiration.
• Existing configurations lack adequate radiation shielding and are prone to bias in atmospheric boundary layer measurements.

Purpose of the Study:

• To develop and evaluate a novel sensor housing for airborne Temperature-Humidity (TH) sensors on multirotor UASs.
• To mitigate issues of radiation shielding, propeller-induced turbulence, and inconsistent aspiration.
• To enable reliable atmospheric boundary layer profiling during both ascent and descent.

Main Methods:

• Designed a modular sensor housing mounted above UAS propellers to utilize rotor-induced pressure deficits for consistent laminar airflow.
• The housing shields sensors from artificial heat sources and wet-bulbing effects, drawing air from outside the rotor wash.
• Conducted extensive flight tests up to 500 m Above Ground Level (AGL) with high UAS speeds (up to 5 m/s).

Main Results:

• The novel housing design ensures consistent sensor aspiration, independent of UAS orientation to ambient wind.
• Flight tests demonstrated reliable measurements of atmospheric boundary layer phenomena.
• A low standard deviation of errors confirmed good agreement between ascent and descent profiles.

Conclusions:

• The developed sensor housing effectively shields airborne sensors from environmental interference and propeller wash.
• This design significantly improves the reliability of atmospheric boundary layer measurements from multirotor UASs.
• The housing is compatible with various UAS platforms and suitable for diverse aerial sensing missions.