MFAM: Miniature Fabricated Atomic Magnetometer for

Autonomous Magnetic Surveys

Bart HoekstraRahul Mhaskar

Drones Applied to Geophysical Mapping Workshop SEG 2017

Unmanned Vehicles –The Future of Geophysics

Drones Applied to Geophysical Mapping 2

REMUS 100 AUV (Source: KONGSBERG)

Modern Robotic Guards (Source: Robotic Assistance Devices)

Liquid Robotics Wave Glider (Source: Liquid Robotics)

X8 Fixed Wing UAV (Source: Feiyu-tech)

→ Autonomous Platform→ Decrease Field Time

→ Survey Difficult to Access Places→ Decrease Risk to Field Personnel

SEG 2017

Implications for Geophysical Sensorson Un-Manned Platforms

→ Reduce

→ Weight

→Power

→Size

→ High Sample Rate

→ Simple Operating Interface

→ Deployment Flexibility

Maintain sensitivity and other critical parameters

Drones Applied to Geophysical Mapping 3SEG 2017

MFAM Critical Specifications

→ Power – 2.5 W per Sensor

→ Weight – Less than 2 lbs in airborne configuration

→ 15 cm3 sensor elements

→ Sample Rate – 1000 Hz.

→ Sensitivity – 1 pT/√Hz

Drones Applied to Geophysical Mapping 4SEG 2017

MFAM Instrument

MFAM Module

Physics Package

Physics Packages

Sensor Driver

Senso

rC

on

nectivity

Application Interface

Application ConnectivityCable

Physics Packages Sensor Driver

MFAM System Architecture

Drones Applied to Geophysical Mapping 5SEG 2017

MagArrow Prototype

Autonomous, fully self-contained drone-mounted magnetometer with similar

performance to existing Cesium Magnetometers

Photos courtesy of Ron Bell of International Geophysical Services

Drones Applied to Geophysical Mapping 6SEG 2017

Autonomous Platform

Photos courtesy of National Energy Technology Laboratory

Package includes• Wi-Fi for Downloading

• Battery• GPS for Timing and Positioning

Drones Applied to Geophysical Mapping 7SEG 2017

Sensor Validation

G-859MFAM

Data courtesy of Ron Bell of International Geophysical Services

Drones Applied to Geophysical Mapping 8SEG 2017

MagArrow Prototype Results

Drones Applied to Geophysical Mapping 9SEG 2017

Survey ProductivityIGS Landfill Survey Same survey area same line spacing

Ground Survey – 3 daysMagArrow Survey – <1 hour

15 minutes of field time

Soccer Fields

• Survey Speed – 7 m/s• Internal Battery runs for 2.5 Hours• WiFi downloading of data during

platform battery swap

Drones Applied to Geophysical Mapping 10SEG 2017

Hardware Features

→ Easy to use – begin data collection within minutes

→ Visible status LEDs to ensure that the system is functioning correctly

→ Internal GPS for timing

→ Hot-swappable battery

→ 1000 Hz Sample Rate

→ Orient sensors to eliminate dead zones

Data courtesy of International Geophysical Services and processed by Scott Thomas

Drones Applied to Geophysical Mapping 11SEG 2017

Software Features

→ App based interface for system health monitoring

→ GPS data and PPS synchronization status

→ Data export to ASCII file or direct import into Geosoft

→ WiFi download – no physical connection

→ Remote update – Field upgradable

→ Commercially Available Batteries

Drones Applied to Geophysical Mapping 12SEG 2017

Benefits of Magnetic Surveying Using Drones

→ Shorten exploration time 10X

→ Survey over inaccessible and hazardous terrain

→ Higher spatial resolution than traditional airborne surveys

→ Easy to export data

→ Less expensive than either airborne or traditional ground surveys

→ No operator input required during survey

Drones Applied to Geophysical Mapping 13SEG 2017

In Summary

→ ~2.5 pounds

→ 2.5 hour battery life and a built-in GPS, On-Board Storage and WiFi connectivity

→ High sample rate and sensitivity

→ Easy to use

→ Full unit commercially available next year –module and development kit available now!

Drones Applied to Geophysical Mapping 14SEG 2017

Photo courtesy of Ron Bell of International Geophysical Services

Drones Applied to Geophysical Mapping 15SEG 2017