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