On-the-go Caliper and Counter Device for Shade and Fruit Tree Nursery Inventory

Management

J.S. Owen Jr., W. Shi, S. Singh, H.M. Stoven, K. Lewis

Seasonal Counts for Inventory

Images by Jim Robbins

Automation of Inventory

Processes for Nurseries

Dr. James Robbins – Extension Specialist

Image by Jim Robbins

Caliper as an Estimate of Grade

Tallymaster – 2003

On-the-Fly Tree Caliper

Measurement

2 Class 3 lasers, 60 Hertz camera

On-the-Fly Tree Caliper

Measurement

Capture multiple frames per tree at

varying angles

Caliper

2 Class 3 lasers

Caliper estimation at 60 times per second (60 Hz)

Filtered from light

Algorithm incorporated to process staked trees

Caliper measured at:

distance of 10 to 20” from tree

6” (±2”) above the graft union or soil travelling 3 mph

Field Caliper GUI User can specify if stakes are used and diameter of stake

Reports optimum measuring distance range and maximum

allowed traveling speed to ensure adequate estimates per

tree (approx. 12)

Unstaked Tree Accuracy

+/- 2.5mm

Unstaked Tree Accuracy

0

20

40

60

80

100

120

140

160

180

200

4 5 6 7 More

Caliper Ests Manual Utool

Num

ber

of

trees

Nursery tree grade

Staked Tree Accuracy

Staked Tree Accuracy

Limitation for staked trees

Need to know the caliper of the stake

Caliper of stake and tree must be significantly different (ratio of

stake caliper to tree caliper)

Left figure shows stakes deemed acceptable, right figure shows

stakes that are not viable.

Staked Tree Accuracy

Counter Software

Graphic User Interface to include user

input, pausing and saving data

On-the-Fly Tree Counter

J frank Schmidt, OR - 45 Sergeant crabapples travelling < 3 mph. Trees

were counted 5 times with an average accuracy of 97%

Willow Drive Nursery, WA - 20 apple small caliper seedlings travelling

approx 2 mph. Trees were counted 10 times with an average accuracy of

95%.

At Dave Wilson Nursery, CA - 50 cherries trees travelling approx 2.5 mph.

Each of the tree cultivars were counted 10 to 20 times with an average

accuracy of 97%

At J frank Schmidt, OR - 45 Gymnocladus seedlings travelling approx 2.5

mph. Each of the tree cultivars were counted 4 times with an average

accuracy of 97%

At J frank Schmidt, OR on 708 Staked 2 year old red pointe maple (½ - 1 ¼

caliper, 12 inch spacing) 91 to 90% accuracy. Low accuracy was result of

a dust film on lens.

Localization

Post-processed

Device: U-blox 6T

Cost: $300 to $400

Sub-meter accuracy

Field tested

○ Spring (WA)

○ Fall (OR)

Tractor track:

raw data in

red

Processed

data in green.

Localization

Tractor’s speed plot: during travel at

~3.0 mph

Localization

http://www.cascrop.com/