Aerial Rock Fragmentation Analysis in Low-Light Condition Using UAV - - PowerPoint PPT Presentation

Aerial Rock Fragmentation Analysis in Low-Light Condition Using UAV Technology

• T. Bamford1
• K. Esmaeili1
• A. P

. Schoellig2

1Lassonde Institute of Mining

University of Toronto

2University of Toronto Institute for Aerospace Studies

University of Toronto

APCOM, August 2017

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 1 / 26

Forecast

We use UAV technology to frequently measure rock fragmentation. In this work we found that: Lighting conditions greatly impact photographic analysis accuracy Artificial lighting applied evenly can improve prediction accuracy and enable measurement in low light conditions

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 2 / 26

Outline

1

Motivation and Problem Statement

2

Related Work

3

Methods

4

Results

5

Summary

6

Future Work

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 3 / 26

Table of Contents

1

Motivation and Problem Statement

2

Related Work

3

Methods

4

Results

5

Summary

6

Future Work

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 4 / 26

Motivation

Post-blast rock fragmentation influences: Comminution energy consumption Mill throughput rates Digging and hauling equipment efficiency Measuring it is important for optimizing a mining operation.

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 5 / 26

Motivation

Unmanned Aerial Vehicle (UAV) technology can measure rock fragmentation: Provide higher spatial- and temporal-resolution data Automate data collection Collect from typically inaccessible and hazardous areas Improve safety for technicians Frequently measure surface to predict internal distribution

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 6 / 26

Problem Statement

To frequently measure rock fragmentation consider: Night shifts in surface mines Underground working conditions However, UAVs equipped with common cameras in poor lighting: Difficult to delineate particles

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 7 / 26

Problem Statement

Two questions this work investigates: How much does poor lighting effect accuracy? Can artificial lighting reduce this effect?

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 8 / 26

Table of Contents

1

Motivation and Problem Statement

2

Related Work

3

Methods

4

Results

5

Summary

6

Future Work

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 9 / 26

Related Work

Limitations for photographic and 3D measurement of rock fragmentation: Limit Photographic 3D techniques Measure surface not internal distribution

• Particle delineation error
• Perspective distortion
• Inability to meaningfully detect fines
• Bamford, Esmaeili, Schoellig (UofT)

Rock Fragmentation Analysis Using UAV APCOM 2017 10 / 26

Related Work

3D techniques using LIDAR and stereo imaging control some limitations, however: Have not enabled automated measurement Currently capture from fixed locations Addition to UAV can be expensive

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 11 / 26

Table of Contents

1

Motivation and Problem Statement

2

Related Work

3

Methods

4

Results

5

Summary

6

Future Work

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 12 / 26

Methods

Compare UAV rock fragmentation measurement using commercial image analysis software with sieve analysis in different lighting conditions for: Controlled lab environment Outdoor Experiment

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 13 / 26

Methods

Compare UAV rock fragmentation measurement using commercial image analysis software with sieve analysis in different lighting conditions for: Controlled lab environment Outdoor Experiment

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 14 / 26

Table of Contents

1

Motivation and Problem Statement

2

Related Work

3

Methods

4

Results

5

Summary

6

Future Work

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 15 / 26

Results

Raw and delineated photos in ideal (a) and dark (b) lighting. a) b)

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 16 / 26

Results

Rock fragmentation analysis results for indoor environment.

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 17 / 26

Results

Illuminance Amount of luminous flux per unit area [lx] Error Area between sieve and estimate curves [percent passing × log(mm)]

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 18 / 26

Results

Distribution error plotted with illuminance measurement for indoor environment.

101 102 103

Illuminance of pile (lx)

2 4 6 8 10

Error (%passing log(mm))

Dark Indoors Dim Uneven Lighting a a a b Artificial Lighting c d ambient lighting Normal Indoors Very Dark

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 19 / 26

Results

Rock fragmentation analysis results for outdoor experiment.

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 20 / 26

Results

Distribution error plotted with illuminance measurement for indoor environment.

100 101 102 103 104

Illuminance of pile (lx)

4 6 8

Error (%passing log(mm))

Dusk Very Dark Pitch Black b a a Cloudy c Artificial Lighting Without Artificial Lighting ambient lighting

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 21 / 26

Table of Contents

1

Motivation and Problem Statement

2

Related Work

3

Methods

4

Results

5

Summary

6

Future Work

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 22 / 26

Summary

In this work we found that: Lighting conditions greatly impact photographic analysis accuracy Artificial lighting applied evenly can improve prediction accuracy

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 23 / 26

Table of Contents

1

Motivation and Problem Statement

2

Related Work

3

Methods

4

Results

5

Summary

6

Future Work

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 24 / 26

Future Work

Items that have been raised during this work: Test concepts in a mining environment Incorporate measurement uncertainty into analysis Configure better cameras (ex. high dynamic range) Light inaccessible areas Increase control over image analysis Understand trade-offs using 3D techniques

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 25 / 26

• mre-researchgroup.com

dynsyslab.org Thank you! Thomas Bamford thomas.bamford@mail.utoronto.ca

Bamford, Esmaeili, Schoellig (UofT) Rock Fragmentation Analysis Using UAV APCOM 2017 26 / 26