Wikipedia

Off-road vehicle

Not to be confused withSport utility vehicle (SUV).

Anoff-road vehicle(ORV), sometimes referred to as anoff-highway vehicle(OHV),overland vehicle,oradventure vehicle,is anyvehicledesigned todriveon non-pavedsurfaces,[1]such astrailsandforest roads,that have rough, uneven, and low-traction surfaces. Off-road vehicles have been popularized through competitive off-road events, such as the annualDakar Rally,[2]which challenges vehicles to navigate harsh terrain across various countries.

Mercedes-BenzUnimogin the Dunes ofErg ChebbiinMorocco.The vehicle'sportal gearaxles provide high ground clearance.

History

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Nicholas II's Packard Twin-6 with Kégresse track, 1917

One of the first modified off-road vehicles was theKégresse track,a conversion undertaken first byAdolphe Kégresse,who designed the original while working forCzarNicholas II of Russia,between 1906 and 1916.[3]The system uses acaterpillar trackwith a flexible belt, rather than interlocking metal segments. It can be fitted to a conventional car or truck to turn it into ahalf-track,suitable for use over rough or soft ground.

After theRussian Revolution of 1917,Kégresse returned to his nativeFrancewhere the system was used onCitroëncars between 1921 and 1937 for off-road andmilitary vehicles.TheCitroëncompany sponsored several overland expeditions with vehicles crossingNorth AfricaandCentral Asia.

A huge wheeled vehicle designed from 1937 to 1939 under the direction ofThomas PoultercalledAntarctic Snow Cruiser,was intended to facilitate transport inAntarctica.While having several innovative features, it generally failed to operate as hoped under difficult conditions and was eventually abandoned in Antarctica.

Early off-road vehicles, such as the U.S.Jeep WagoneerandFord Bronco,the BritishRange Rover,and thestation wagon-bodiedJapaneseToyota Land Cruiser,Nissan Patrol,andSuzuki Lj's serieswere all had bodies similar to those of astation wagon,on a body comparable to that of alight truck,withfour-wheel-drivedrivetrains.Later, during the 1990s, as off-road vehicles became more popular, more companies started to produce their own line of what became known as Sport Utility Vehicles[4].Around this time, manufacturers began to add more features to allow off-road vehicles to compete in the consumer market with regular vehicles. Over time, this evolved into what we call theSUVtoday. It also evolved into the newercrossover vehicle,whereutility and off-road capabilitywere sacrificed for better on-road handling and luxury.

Technical details

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Swedish HägglundsBv206with wide rubber tracks

To be able to drive off thepavement,off-road vehiclesneed several characteristics: They need to have a lowground pressure,so as not to sink into soft ground, they need a lot ofground clearance,to not get stuck on obstacles, and they need to keep theirwheelsortrackson the ground, so as not to lose traction. Wheeled vehicles accomplish this by having a suitable balance of large or additional tires, combined with tall andflexible suspension.Tracked vehiclesaccomplish this by having wide tracks and flexiblesuspensionon the road wheels.

RussianGAZ-34039[ru]

The choice of wheels versus tracks is one of cost and suitability. A trackeddrivetrainis more expensive to produce and maintain. Wheeled drivetrains are cheaper and give a higher top speed. A tracked drivetrain has greater off-road capability.

Tiresplay a significant role for any off-road vehicle equipped with wheels, ensuring optimal traction to keep it moving. Theoff-road tiretread types vary depending on the terrain type. The most common types of off-road tires are A/T (stands for "All Terrain" ) and M/T (stands for "Mud Terrain" ). While the A/T tires perform excellently on the sand, they are barely usable in the mud. There are also unique Sand Blaster andMud boggingtires used for the most challenging terrains such as dirt, sand, and even water to maintain traction at extreme angles and high speeds (off-roadmotorsport).[5]

Most off-road vehicles are fitted withlow gearing.This allows the operator to optimize theengine'savailable powerwhile moving slowly through challenging terrain. Aninternal combustion enginecoupled to a standardgearboxoften has an output speed too high. The vehicle often has one of two things, either a very low ( "granny" ) first gear (like the all-wheel driveVolkswagen Transporterversions) or an additional gearbox in line with the first, called areduction drive.Some vehicles, like the Bv206 in the picture on the right, also havetorque convertersto reduce the gearing.[6]

Criticism

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Safety

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Main article:Criticism of sport utility vehicles

SUVsare built with higherground clearance,foroff-roaduse, and thus have a highercenter of gravity,[7]therefore increasing the risk of rollover. When an SUV turns, the vehicle's mass resists the turn. This carries the SUV's weight forward, thus allowing the traction from the tires to create a lateralcentripetal forceas the vehicle continues through the turn. The conflict between the topweightof the SUV's desire to go straight and thefrictionof thetireson theroadcauses the bottom of the vehicle to move away and out from under the SUV during a turn.

SUVs are more likely to be in rolloveraccidentsthanpassenger cars.According to a study conducted in theUnited States,SUVs have twice the fatality rate of passenger cars and have nearly triple the fatality rate in rollover accidents.[8]

In the United States,light trucks(includingSUVs) represent 36 percent of all registered vehicles. They are involved in about half of the fatal two-vehicle crashes with passenger cars, and 80 percent of these fatalities are to occupants of passenger cars.[8]

Environment

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In theUnited States,the number of ORV users since 1972 has climbed sevenfold—from five million to 36 million in 2000.[9]Government policies that protect wilderness but also allow recreational ORVs, have been the subject of some debate within the United States and other countries.[10]

All trail and off-trail activities impactnatural vegetationand wildlife, which can lead toerosion,invasive species,habitat loss,and ultimately,species loss[11][12][13]decreasing anecosystem's ability to maintainhomeostasis.[14]ORVs cause greater stress to the environment thanfoot trafficalone, and ORV operators who attempt to test their vehicles against natural obstacles can do significantly more damage than those who follow legal trails.[15][16]Illegal use of off-road vehicles has been identified as a seriousland managementproblem ranked with dumpinggarbageand other forms ofvandalism.[17]Many user organizations, such asTread Lightly!and theSierra Club,publish and encourage appropriatetrail ethics.[18]

ORVs have also been criticized for producing more pollution in areas that might normally have none. In addition tonoise pollutionthat can cause hearing impairment and stress in wildlife,[19]according to theU.S. Forest Service,old-styletwo-stroke engines(no longer a component of new off-road vehicles, although some are still in use) "emit about 20 to 33 percent of the consumed fuel through the exhaust" and "discharge from two-stroke snowmobile engines can lead to indirect pollutant deposition into the top layer of snow and subsequently into the associated surface and groundwater."[20][21]In 2002, theUnited States Environmental Protection Agencyadopted emissions standards forall-terrain vehiclesthat "when fully implemented in 2012... are expected to prevent the release of more than two million tons ofair pollutioneach year—the equivalent of removing thepollutionfrom more than 32 million cars every year. "[22][23]

Civilian use

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Common[where?]commercial vehicles used for off-roading include four-wheel-drivepickup trucksandSUVssuch as theFord F-Series,Jeep Wrangler,andToyota Land Cruiser,among others. Typically, owners will perform additional modifications to the wheels, tires, suspension, and body to improve their performance off-road. Several decommissionedmilitary vehicleshave also been used by civilians, including theJeep CJand theAM GeneralHummer.Some, like the earlyLand Rovers,were adapted to military use from civilian specifications. Specialized off-road vehicles includeUtility terrain vehicles(UTVs),All-terrain vehicles(ATVs),dirt bikes,dune buggies,rock crawlers,andsandrails.

All-terrain vehicle

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This section is an excerpt fromAll-terrain vehicle.[edit]
The ATV is commonly called a four-wheeler in Australia, South Africa, parts of Canada, India, and the United States. They are used extensively in agriculture, because of their speed and light footprint.

Anall-terrain vehicle(ATV), also known as a light utility vehicle (LUV),[24]a quad bike or quad (if it has four wheels), as defined by theAmerican National Standards Institute(ANSI), is a vehicle that travels on low-pressure tires, has a seat that is straddled by the operator, and has handlebars. As the name implies, it is designed to handle a wider variety of terrain than most other vehicles. It isstreet-legalin some countries, but not in most states, territories and provinces of Australia, the United States, and Canada.

By the currentANSIdefinition, ATVs are intended for use by a single operator, but some ATVs, referred to as tandem ATVs, have been developed for use by the driver and one passenger.[25]

The rider sits on and operates these vehicles like a motorcycle, but the extra wheels give more stability at slower speeds. Although most are equipped with three or four wheels, six or eight wheel (tracked) models exist and existed historically[26]for specialized applications. Multiple-user analogues with side-by-side seating are calledutility terrain vehicles (UTVs) or side-by-sidesto distinguish the classes of vehicle. Both classes tend to have similarpowertrainparts.Engine sizesof ATVs for sale in the United States as of 2008 ranged from 49 to 1,000 cc (3.0 to 61cu in).

Other applications

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Military vehicle

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The military market for off-road vehicles used to be large, but, sincethe fall of the Iron Curtainin the 1990s, it has dried up to some extent. TheU.S. jeeps,developed duringWorld War II,coined the word many people use for any light off-road vehicle. In the U.S., the Jeeps' successor from the mid-1980s was the AM GeneralHMMWVseries. TheRed Armyused theGAZ-61andGAZ-64duringWorld War II.TheEastern Blocused theGAZ-69andUAZ-469in similar roles.

Experimental vehicle

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  • Experimental marsh buggy, 1928, stuck in mud.

Commercial vehicle

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  • Off-road bus in Iceland.

Scientific vehicle

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Expedition vehicle

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Vehicles used as the primary transport in anexpedition,not for profit, scientific research or personal use.

See also

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References

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Notes

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  1. ^"Off-Road Vehicle Act"(Web).New Brunswick Acts and regulations.Attorney General, New Brunswick, Canada. June 27, 1985.Retrieved2007-10-17.
  2. ^"Dakar Rally".Retrieved2024-11-08.
  3. ^MiG-registeret
  4. ^"Gone without a Trace: These Are the Forgotten SUVs".Car and Driver.2018-03-05.Retrieved2024-11-21.
  5. ^"Mud terrain vs all-terrain tires – pros, cons & comparison".offroadium.com.Retrieved2017-04-17.
  6. ^https://pioneerrentals.ca/wp-content/uploads/2019/04/Hagglund_BV206D6_en.pdf[bare URL PDF]
  7. ^Rodney E. Slater (U.S. Transportation Secretary) (April 9, 1998)."Secretary Slater Proposes New Label; Warning of Rollover Danger for Sport Utility Vehicles".News Release.National Highway Traffic Safety Administration. Archived fromthe original(Web)on 2007-02-13.Retrieved2007-05-17.
  8. ^abJeffrey W. Runge, M.D. (Administrator, National Highway Traffic Safety Administration) (February 26, 2003)."The Honorable Jeffrey W. Runge, M.D. Administrator National Highway Traffic Safety Administration Before the Committee on Commerce, Science, and Transportation United States Senate"(Web).Testimony before the Committee on Commerce, Science, And Transportation, United States Senate.National Highway Traffic Safety Administration.Retrieved2007-05-17.{{cite web}}:CS1 maint: multiple names: authors list (link)
  9. ^"Forest Service Rule Revs Up Off-Road Vehicle Fight"(Web).Article.Environment News Service (ENS). July 8, 2004.Retrieved2007-06-24.
  10. ^van Wagtendonk, Jan W. (2003)."Role of Science in Sustainable Management of Yosemite Wilderness"(PDF).USDA Forest Service Proceedings RMRS-P-27. 2003.USDA Forest Service.Retrieved2007-06-24.
  11. ^Rice, Kathleen C."National Collection of Imperiled Plants – Pholisma sonorae".Center for Plant Conservation.Retrieved8 June2012.
  12. ^"Mojave lizard may get protection; off-road vehicles are cited as threat".Los Angeles Times.12 January 2008.Retrieved2 May2015.
  13. ^"Officials seek to protect desert reptile".Las Vegas Review-Journal.Retrieved2 May2015.
  14. ^"Technical Notes"(PDF).Conserving Natural and Cultural Resources on Department of Defense Lands; Case Studies from the DoD Conservation Program (Page 13).US Department of Defense. 2004. Archived fromthe original(PDF)on 2007-06-28.Retrieved2007-06-24.
  15. ^Kristine Sowl & Rick Poetter (April 16, 2004)."Impact Analysis of Off-Road Vehicle Use for Subsistence Purposes on Refuge: Lands and Resources Adjacent to the King Cove Access Project"(PDF).Izembek National Wildlife Refuge (page 6).US Fish and wildlife services Alaska. Archived fromthe original(PDF)on 2007-06-28.Retrieved2007-06-24.
  16. ^"Recreation Management Goals and Strategies"(PDF).Capitol State Forest Recreation and Public Use Plan—Part II (Page 45).Washington State Department of Natural Resources. Archived fromthe original(PDF)on 2007-02-21.Retrieved2007-06-24.
  17. ^"Chapter 11. Field Management Status"(Web).Land Management (11.5.2 Identified Concerns of the Parks Department).Central Pine Barrens Joint Planning and Policy Commission.Retrieved2007-06-24.
  18. ^"Codes of Ethics Advocated by Groups Outside of Ontario"(Web).Trail Ethics.Trent University. January 16, 2007.Retrieved2007-06-24.
  19. ^"The Impacts of Off-Road Vehicle Noise on Wildlife".Archived fromthe originalon 2010-12-25.Retrieved2009-01-19.
  20. ^"Chugach National Forest – Home"(PDF).Retrieved2 May2015.
  21. ^"Addressing the Ecological Effects of Off-Road Vehicles".Archived fromthe originalon 2008-11-28.Retrieved2009-01-19.
  22. ^"New Air Pollution Rules Target Off-Road Vehicles"(Web).Article.Environment News Service (ENS). September 17, 2002.Retrieved2007-06-24.
  23. ^"Final Rule for Cleaner Large Industrial Spark-Ignition Engines, Recreational Marine Diesel Engines, and Recreational Vehicles"(Web).US Environmental Protection Agency. March 6, 2006.Retrieved2007-06-24.
  24. ^"24556 Demonstrate knowledge of the safe operation of a light utility vehicle (LUV)"(PDF).NZQA.2019.
  25. ^"Standards for All Terrain Vehicles and Ban of Three-Wheeled All Terrain Vehicles; Proposed Rule".Consumer Product Safety Commission (Federal Register). 10 August 2006. Archived fromthe originalon 13 January 2008.Retrieved26 December2007.
  26. ^"How Many Wheels Did The Original ATV Have? – ATV Trail Reviews".24 August 2021.Retrieved2022-02-22.

Bibliography

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  • Allen, Jim; Weber, James J. (2021).The Four-Wheeler's Bible: The Complete Guide to Off-Road and Overland Adventure Driving(3rd ed.). Beverly, MA, USA: Motorbooks.ISBN9780760368053.
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Media related toOff-road vehiclesat Wikimedia Commons

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