From horses, through steam and diesel, to electric and robotic

horse-drawn Fresno scraper digging water-supply ditch

A portable engine; a precursor to modern engineering vehicles

An early gasoline-powered tractor

Heavy equipment circa 1922

Until the 19th century and into the early 20th century heavy machines were drawn under human or animal power. With the advent of portable steam-powered engines the drawn machine precursors were reconfigured with the new engines, such as the combine harvester. The design of a core tractor evolved around the new steam power source into a new machine core traction engine, that can be configured as the steam tractor and the steamroller. During the 20th century, internal-combustion engines became the major power source of heavy equipment. Kerosene and ethanol engines were used, but today diesel engines are dominant. Mechanical transmission was in many cases replaced by hydraulic machinery. The early 20th century also saw new electric-powered machines such as the forklift. Caterpillar Inc. is a present-day brand from these days, starting out as the Holt Manufacturing Company. The first mass-produced heavy machine was the Fordson tractor in 1917.

The first commercial continuous track vehicle was the 1901 Lombard Steam Log Hauler. The use of tracks became popular for tanks during World War I, and later for civilian machinery like the bulldozer. The largest engineering vehicles and mobile land machines are bucket-wheel excavators, built since the 1920s.

"Until almost the twentieth century, one simple tool constituted the primary earthmoving machine: the hand shovel – moved with animal and human powered, sleds, barges, and wagons. This tool was the principal method by which material was either sidecast or elevated to load a conveyance, usually a wheelbarrow, or a cart or wagon drawn by a draft animal. In antiquity, an equivalent of the hand shovel or hoe and head basket—and masses of men—were used to move earth to build civil works. Builders have long used the inclined plane, levers, and pulleys to place solid building materials, but these labor-saving devices did not lend themselves to earthmoving, which required digging, raising, moving, and placing loose materials. The two elements required for mechanized earthmoving, then as now, were an independent power source and off-road mobility, neither of which could be provided by the technology of that time."^[1]

Container cranes were used from the 1950s and onwards, and made containerization possible.

Nowadays such is the importance of this machinery, some transport companies have developed specific equipment to transport heavy construction equipment to and from sites.

Most of the major equipment manufacturers such as Caterpillar,^[2] Volvo,^[3] Liebherr,^[4] and Bobcat have released or have been developing fully or partially electric-powered heavy equipment. Commercially-available models and R&D models were announced in 2019 and 2020.^[5]

Robotics and autonomy has been a growing concern for heavy equipment manufacturers with manufacturers beginning research and technology acquisition.^[6] A number of companies are currently developing (Caterpillar and Bobcat) or have launched (Built Robotics) commercial solutions to the market.

Images

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  The Caterpillar D10N bulldozer evolved from tracked-type tractors and is characterized by a steel blade attached to the front that is used to push other equipment and construction materials, such as earth.
• 
  The bucket excavator Komatsu PC210-LC.
• 
  The wheel trencher MARAIS SMC 200 R.
• 
  Iron bar reinforced foundation piles are driven with a drilling machine, concrete pump, mixer-truck, and a specialized auger that allows pumping concrete through its axis while withdrawn.
• 
  Fixed crane in a coal mine in Germany
• 
  Caterpillar D9L bulldozer, excavators and other heavy equipment vehicles parked near a quarry in Israel
• 
  Bucket wheel excavators in Garzweiler surface mine, Germany
• 
  Wheel loader
• 
  Grader cleaning and leveling
• 
  Heavy duty excavator with large bucket equipped.
• 
  Landfill compactor (tamping tip)
• 
  Komatsu Dozer pushing coal on the job site
• 
  A wheeled front loader tractor equipped with a large bucket elevated by hydraulic rams.
• 
  Folded conveyor on a tracked grinder

• Military engineering vehicles
• 
  The militarized Caterpillar D9 armored bulldozer allows for earthmoving projects in a combat environment. In the picture: IDF Caterpillar D9R.
• 
  The militarized Huta Stalowa Wola backhoe loader in Poland which is subsidiary of LiuGong China
• 
  Military scraper
• 
  PiPz Dachs armoured engineering vehicle of the German Army (2008)
• 
  Temporary roads deployment complex during the "Armiya 2021" exhibition

Ownership cost

To classify as an ownership cost an expense must have been incurred regardless of if the equipment is used or not. These costs are as follows:

Depreciation can be calculated several ways, the simplest is the straight-line method. The annual depreciation is constant, reducing the equipment value annually. The following are simple equations paraphrased from the Peurifoy & Schexnayder text:

Operating cost

For an expense to be classified as an operating cost, it must be incurred through use of the equipment. These costs are as follows:^[10]

The biggest distinction from a cost standpoint is if a repair is classified as a major repair or a minor repair. A major repair can change the depreciable equipment value due to an extension in service life, while a minor repair is normal maintenance. How a firm chooses to cost major and minor repairs vary from firm to firm depending on the costing strategies being used. Some firms will charge only major repairs to the equipment while minor repairs are costed to a project. Another common costing strategy is to cost all repairs to the equipment and only frequently replaced wear items are excluded from the equipment cost. Many firms keep their costing structure closely guarded as it can impact the bidding strategies of their competition. In a company with multiple semi-independent divisions, the equipment department often wants to classify all repairs as "minor" and charge the work to a job – therefore improving their 'profit' from the equipment.