Smart Vision. Smart Decision.

Presenter: Danny Hajicek Software and Electrical Design Engineer

How payload technology can optimize UAS-based agricultural

aerial imaging operations

Danny.Hajicek@fieldofviewllc.com Fieldofviewllc.com

Outline !  Why UAS for imaging? !  Camera options !  Post processing hurdles !  Direct georeferencing !  Input data timing and sensor accuracy !  Camera triggering !  Optimization matters / Limited time

“On demand” 5cm resolution

Scheduled 1m resolution

6 day revisit 5m resolution

16 day revisit 30m resolution

Availability and Resolution

High Resolution DSLR or MILC !  Color imagery (RGB)

!  High resolution !  Simple to manage !  Red, Green, Blue

!  False color imagery (CIR) !  Converted (NIR, Green, Blue) !  Purpose-built (NIR, Red, Green)

Multispectral Cameras

Image Processing !  Stitch multiple images

into single mosaic !  Georeferencing

!  Ground control points !  Position (and attitude)

metadata !  Mosaic requirements

!  Coverage of AOI !  Sufficient image overlap

Agisoft PhotoScan Pro

Sensor Positioning

Positioning Challenges

!  Maintain flight line !  Pushed by wind !  Autopilot not tuned !  Incorrect altitude

!  Camera fault !  Poor flight planning !  Typically not realized

until mosaicking is attempted back at the office

Coverage Verification !  Quality control

!  1st visit success => profit !  Must happen quickly and

on-site !  Actionable visualization

!  Direct georeferencing !  Use position/attitude to

calculate image placement !  Can be highly automated !  Sensor accuracy affects

results

Effects of Sensor Accuracy !  GPS accuracy

!  Single frequency GPS ≈ 3m !  Dual frequency GPS ≤ 1m !  Augmented GPS ≤ 0.5m

!  IMU accuracy !  Autopilots ≥ 1° !  Medium grade IMU ≤ 1° !  High grade IMU ≤ 0.05° !  Placement accuracy

depends on altitude 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00

10.00

0 500 1000 1500 2000 2500 3000

RSS

Err

or (m

)

Altitude (ft)

Effects of Sensor Accuracy !  Autopilot data

!  Low sensor accuracy !  Meant for navigation, not

direct georeferencing !  No confidence in results

!  GPS/IMU accuracy !  Single frequency GPS !  0.25° pitch/roll !  0.75° heading

Single frequency GPS, 0.25° pitch/roll, 0.75° heading (VectorNav VN-200 GPS/IMU)

Association Accuracy "  Accurate GPS/IMU "  Dedicated attitude/position photo

association processor

GeoSnap VN-TC on an ADC Lite

Camera Interface Options "  Hard wired "  Infrared "  Serial

GeoSnap VN-TC on a Mini-MCA

GeoSnap VN-SLR on a Canon 6D

Intelligent Triggering Achieve required overlap, without capturing extraneous images

Wind Wind Wind

Traditional Time based Enhanced distance based Efficient distance based with pitch/roll disable

Big Picture "  Commercial Operations

!  Slim margins in Ag !  Successful = optimized

Smart Vision. Smart Decision.

Presenter: Danny Hajicek Software and Electrical Design Engineer

How payload technology can optimize UAS-based agricultural

aerial imaging operations

Danny.Hajicek@fieldofviewllc.com Fieldofviewllc.com