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A Review of UAS

Magnetometers

R. S. BellGeophysicist & geoDRONEologist

September 29, 2017

SEG Near Surface Technical Section

International Geophysical Service, LLCTel: 303-462-1466 e-mail: rbell@igsdenver.com www.igsdenver.com

SEG 2017 Annual Meeting Post-Conference Workshop

Drones Applied to Geophysical Mapping

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sUAS geoscience data and applications

Color Photographs

Near Infrared

Short Wave Infrared

Thermal Infrared

Magnetic

vegetation stress (NVDI)

soil and rock type \ alteration zones

groundwater seeps

thermal emissions \ process managementgaseous emissions

rock type variation / alteration zones

structural mapping

buried objects & UXO

infrastructure

LiDAR

Multi- / hyper- spectral

ground surface

up-to-date photomosaic base map

land surveyin g \ vertical structure inspections

digital elevation model / digital surface model

biological species ID and inventory

assets / project work flow / security

high definition photo-geological mapping

subsurface

ElectroMagnetic (EM)

Color Video (4K)

point cloud of elevations / 3D surfaces

digital elevation model / digital surface model

Gamma Ray Spectrometry geological mapping / hazard detection

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The Evolution of Magnetometer

Technology as it pertains to Drones

2) adapt existing technology

- airborne Cesium magnetometers (i.e.the current state of the art) are appropriate for

larger UAVs but are too heavy and power hungry for effective use with drones. Geo-

positioning of data is tied to aircraft navigation system.

1) use existing technology

- magnetometer manufacturers reduced the weight of their current magnetometers

but were not able to reduce the power requirements. In some cases, the geo-

positioning is tied to the aircraft navigational systems in others, a separate GPS is

located with the magnetic field sensor.

3) create innovative solutions re-engineered conventional older technology i.e. three axis fluxgate magnetometer

invent new sensing technology i.e. micro-fabricated atomic magnetometer (MFAM)

locate a GPS antenna with the magnetic field sensor0

precisely measure altitude of sensor

improve altitude control of aircraft

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UAS Magnetometers Optically Pumped Magnetometers

GEM Systems (http://www.gemsys.ca/)

Scintrex (http://www.scintrexltd.com)

Geometrics Inc. (http://www.geometrics.com/)

Fluxgate Magnetometer (3 axis)

Mobile Geophysical Technologies (http://www.mgt-geo.com/)

Bartington Instruments (http://www.bartington.com/) LEMI Sensors (http://www.lemisensors.com/)

Micro Fabricated

Atomic Magnetometer

GEM Systems

GSMP35UAV

Geometrics, Inc.

3 Axis Fluxgate

Mobile Geophysical

Technologies

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UAS Potassium Magnetometer

Potassium Magnetometer by GEM Systems Solutions

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UAS Potassium Magnetometer

Monarch UAS gradient magnetometer

Monarch UAS Magnetic Gradiometer

Speed: 70 km/hr (cruise)

50 km/hr (stall)

Range (with gradiometer payload): 1.5 hours

Weight: 22 lbs

Wingspan (sensor separation): 3.2 meters

Operation limits: 13.0 km from control

(upgradeable to 80.0 km)

Sensor type: potassium, optically pumped

Sensitivity: 0.3pT

Range: 15,000 to 120,000 nT

Gradient Tolerance: 50,000 nT/m

Sample rates: 1, 5, 10, & 20 Hz

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Potassium Magnetometer by GEM Systems Solutions

AirBird

GSMP 35U, GPS, radio link, laser altimeter

weight= 3.6 kg (7.9 lb)

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Cesium Magnetometer by Scintrex Scientific Sensors, Ltd.

Scintrex CS-VL

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3 axis Fluxgate Vector Magnetometer

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Fixed Wing Installation

3 axis Fluxgate Vector Magnetometer

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Fluxgate Magnetometer

adapted for use with a hexacopter

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Micro Fabricated Atomic Magnetometer

adapted for use with a drone

→ Power – 2.5 W per Sensor

→ Weight – Less than 2 lbs.

→ 15 cm3 sensor elements

→ Sample Rate – 1000 Hz.

→ Sensitivity – 1 pT/√Hz

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Micro Fabricated Atomic Magnetometer

adapted for use with a drone

prototypeweight: 2.3 kg ( 5.1 lb)

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