1. Sensing of temperature, humidity, and pressure in a MEMS remote aerial payload
Undergraduate student: Matthew Nakamura
PI: Assistant Prof. Joseph J. Brown
Office: Department Office:
Web:
Department of Mechanical Engineering, UH Mānoa

2. Q: How can we directly sense environmental conditions in air column?
A: MEMS environmental sensor payload with independent power and data transmission.
Mobile power:
9V battery
Base station
Payload

3. 8-week Design-Build-Test cycle
8/31 project start
10/10 operational electronics
10/18 casing prototyped, operation in lab
10/25 field operation
One undergraduate student, <$100

4. Bosch BME280 Environmental Sensor $20+shipping 1.8 µW when active
Temp: -40 to + 85 °C
Pressure: 30 – 110 kPa
Humidity: accuracy to ±3% RH
Size: 2.5 x 2.5 x 0.95 mm

5. Data Handling and Transmission
Arduino Nano microcontroller
1.4 W at full power
$22 + shipping
Transceiver NRF24L01, Nordic Semiconductor
37.2 mW when in use
2 MBps data rate
Clear line of sight needed
2.4 GHz channel
$12 + shipping

6. Combined System Total mass incl. battery: 114.53 g
Dimensions 10 x 6.5 x 2 cm
Volume: 130 cm3
Combined System
Microcontroller
Sensor
Transceiver

7. Unpackaged base station
Transceiver NRF24L01, Nordic Semiconductor
Arduino Uno microcontroller
Direct connection to computer USB

8. Live remote sensing operation

9. With 3 toy drones, not quite enough load capacity

10. Flight Test 10/25: Enough Capacity, Some Data Hiccups

11. Other sensor systems can be similarly implemented or added.
Conclusions
In 8 weeks we prototyped and operated a mobile environmental sensing payload.
Other sensor systems can be similarly implemented or added.
Shrink footprint by consolidating electronics, sensors, and packaging, and by device miniaturization.

12. Materials integration from fundamentals to applications
This work brought to you by: UHM Micro/Nano Lab Asst. Prof. Joseph J. Brown, Ph.D. Department of Mechanical Engineering University of Hawai‘i at Mānoa
Materials integration from fundamentals to applications
Applied Research Themes
Freestanding nano-thickness structure.
Interfaces: Structural, fluid, electromagnetic
Microdevice engineering
Nanomaterial-based fabrication
Further reading:
US Patent , issued March 2018.
J.J. Brown et al. Nanotechnology, 2016, 27,
N.T. Eigenfeld, et al. Advanced Materials, 2014, 26, 3962.
Acknowledgments:
Applied Research Lab, UH Mānoa
Micro/Nano Group members
Mechanical Engineering Department
Marvin Young for connection to ARL
Thermoacoustic transducer made with 34 nm thick nanobridges.