Innovative Ideas In Steep Slope Logging

Hunter Harrill, Assistant Professor of Forest Operations

Humboldt State University

SWERI Seminar March 2nd, 2021

Overview

• Steep Slope LoggingOperations• New machinery

• New tools

• New techniques

Steep Terrain Challenges

• Many forests globally on ‘steep’ terrain (>40% slope or 22°)• Environment- Can be sensitive requiring

greater care & planning

• Safety- More exposure to hazards than especially tree falling and choker-setting

• Productivity- Lower than ground-based logging (i.e. long distances & cycle times)

• Costs- Higher than ground-based logging due to increased labor & specialized equipment

Cable-assist Historical Development • Forestry: late 80’s on Forwarders to match

Harvester capability on slope.

• Simple mechanical direct drive to sophisticated computer controlled integrated winch systems

• 2000’s expanded to harvesters…

• 800+ commercial units in use (Europe)

• In last decade expanded to New Zealand, Canada, Pacific Northwest & South America

Winch-assist machines

How Do They Work?

“Its all about stability & traction!”

Tethered Machinery Conclusions

• Technology well established

• It is a “step change” to felling & extraction on steep slopes

• It provides more stability & traction

• Best used with: 1) experienced operator with 2) purpose built machine on 3) stable & strong soils• When bottleneck is felling or yarding

Grapple Carriage Expansion

New cabs & control systems for older yarders

• Designed to optimize controls & ergonomics

• Simplified 2 joystick controls

• PLC Electronic controls • Electric over air or hydraulics• Fully programmable• Easy diagnostics

• Alarms & distance indicators

• Gives the precision required forsuccessful grapple yarding!

Tension Monitoring App

• Customizable

• Scroll and zoom

• Color-coded zones for SWL levels• Statistics for

operating time

• Help train operators

• New type of display

• Live streaming graph (e.g. hospital heart rate monitor)

New smaller yarders & yoaders/excavator yarders

Courtesy of Summit Equipment

European Technology• Diesel electric hybrids

• 70% less fuel use (multiple weeks between refuelling)

• 2000 hr service intervals (5 litres oil & standard filters)

• Electric winches = smooth control & variable continuous power• Highest torque at lowest speed• Constant pull over range of drum layers

• Automated controls

• Carriage battery for clamps and slack pulling & recharges on outhaul

Improved payload analysis tools

• Examples: CHPS & RoadEng

• Based of Logger PC & SkylineXL

• CHPS fully integrated into ArcMapas add-in program/toolbar

• Easy as 2 clicks

• Automates & optimize spans

• Covers a range of skyline systems & configurations• Can easily download profiles to

HarvestNav App in felling machine

HarvestNav App

Drones to aid set-up

• Flies synthetic strawline/haywire • 7mm Dyneema

• ≈40g/meter

• 7 tonne breaking strength

• Reduced man-power & time• 2 workers

• <30 minutes

Camera Systems

Tele-operated feller-buncher

Remote-controlled Volvo EC290 mobile tailhold

• Fast line shifts!

• No person required

• Remotely controlled by yarder operator

• Camera systems for guidance

Semi-autonomous forwarding and the future

• Machine pictured inuse for nearly a decade!

• Technology improving & extending to forwarders.• Multiple sensors

required

• Have to program & train computer system

• Conditions always changing!

Conclusions• There are a number of new

developments out there and more to come…• Success still dependant on engagement

and cooperation

• Stop talking about why it won’t work!• Ask yourself “how can we make it

happen?”

• Trying innovative techniques & equipment takes a collaborative approach !• Proven model- many

programs/examples exist