A velomobile (), velomobiel, velo, or bicycle car is a human-powered vehicle (HPV) enclosed for aerodynamic advantage and/or protection from weather and collisions.Frederik Van De Walle. The Velomobile as a Vehicle for more Sustainable Transportation , Retrieved on 23 November 2007. Velomobiles are similar to recumbent bicycles, pedal go-karts and tricycles, but with a full fairing (aerodynamic or weather protective shell) and are not to be confused with purpose-built mobiles for speed records. Fully faired vehicles with two wheels are generally called Streamliners and have set many speed and distance records.records
Though fast in their own right, velomobiles are considered much more suitable for the street than two-wheeled streamliners. Using three or more wheels can have advantages for everyday use, including the ability to stop and start unaided, better stability, cross-wind handling, etc., though there are arguments made that the multiple track machines (three or more wheels) have aerodynamic disadvantages due to the drag of the extra wheels and the surface contact points.A good discussion on bicycle wheel aerodynamics is here. In practice though, velomobiles continue to be close to their two-wheel cousins in performance.velomobiles continue to be close to their 2 wheel cousins in performance
There are few velomobile manufacturers; some are home-built. Some models have the operator's head exposed; this has the advantage of giving the operator unobstructed vision, hearing, and some cooling, with the disadvantage of being potentially more exposed to weather and less aerodynamic. Fully enclosed machines can suffer from heat or humidity issues as well as potential noise issues.
The typical drive traintypical drive train of a velomobile is not unlike a bicycle or recumbent. It will consist of a front bottom bracket with one or more chainrings, and a rear derailleur. Depending on the configuration of the velomobile there may be any number of idler pulleys, and chaintubeschaintubes along the drive train to manage and protect the chain. One of the defining characteristics of most velomobiles is that the chain and drivetrain components are protected from weather and the road.
History
Before World War II, built a small four-wheeled 'bike'-car for his son. Mochet built many models of small vehicles called "Velocar". Some models had two seats, most were pedal powered, but as the years went by, many were fitted with small engines.The Real History of the Recumbent Bicycle Retrieved on 26 March 2008. Mochet Velocars use a thin wood/plywood body on a steel frame.
Some other early velomobiles use a fabric body or "skin" sewn to fit loosely on closely spaced wires or tubes, then painted or "doped" with a liquid that dries and shrinks the fabric to a tight fit on the wire/tube supports. The approach was used widely on early airplanes, and has the advantage of light weight with relatively low-technology materials. It is sometimes called "bird cage" construction because the support looks similar to closely spaced wires used in construction of bird cages, and because the wire/tube support outline shows through once the fabric is tight. Some disadvantages of this approach are the cost of construction, due to the many interconnected supports; and that the shape is that of many flat panels, which limits smoothness of the skin and thus limits the aerodynamics.
In the 1970s, the People Powered Vehicle was produced. It was a two-seat, "sociable" tandem with a steel sub frame and molded plastic body. It was well designed and weighed something over 50 kg (110 lb); a recently restored version weighs 59 kg or 130 lb. However, it had flaws in the execution that doomed it as a practical, everyday vehicle. Positive features, such as easily adjustable and comfortable seats, independent pedalling for both passenger and driver, adequate cargo space and relatively good weather protection, could not overcome the negative features, such as a complex, heavy and badly spaced three-speed gear box, ineffective brakes, and pedals that slid on sleeve bearings on steel shafts, which made it difficult to use as an everyday vehicle.
In Sweden, a two-seat design called Fantom was sold as blueprints and became very popular; over 100,000 copies of the blueprints were sold, but few were actually completed. The downfall of these early 'bicycle' cars came when the economy improved and people chose automobiles.
Modern/contemporary velomobiles
Builders continued to make "one-off" velomobiles, but for a time none were available commercially. In the 1970s, Carl-Georg Rasmussen rediscovered Fantomen; he redesigned it and in 1983 started selling a production version called Leitra. Leitra velomobiles have been in continuous production since then (as of 2017), with current models evolved/improved from the originals.
There are many ways to build a velomobile. One modern design is "body-on-frame", in which a velomobile is made from a not-faired cycle plus a body. A standard cycle may be used, but often a custom cycle is used with special fittings to mount the body; the use of special fittings tends to improve fit and durability, and can also reduce weight. Body-on-frame construction allows flexible configuration: the body may be of any construction, as it does not need to be self-supporting, and various bodies can be used with various frames. Also, the body may be removed so the cycle alone can be used. However, the overall weight of body-on-frame is often higher than alternatives, as the body does have some intrinsic strength, yet this is not used to reduce the weight of the frame.
Another modern design is the , using aluminum sheet formed and riveted to make the fairing and the structure in one piece. This approach is sometimes called monocoque or "unit" construction; it was used in airplanes before 1920. Labor costs to build an Alleweder are significant due to the many rivets and rivet holes. Also, the choices of aerodynamic shapes are limited by the formability of the aluminum sheet. That said, aluminum is relatively inexpensive, and as of 2017 Alleweders can be often be bought for less than other designs; they can also be bought as kits, to reduce out-of-pocket cost. Aluminum can also be repaired relatively easily, and aluminum, which is homogeneous, can be recycled more easily than many composite materials.
Another common modern design is a monocoque shell, often made of fiber-reinforced plastic or "FRP", plus sub-frames of welded aluminum tubes. FRP can be used to produce a wide range of shapes, and thus can improve aerodynamics over approaches such as "birdcage" and aluminum-sheet monocoque. FRP can also use fibers with high strength-to-weight ratio that in velomobiles can save several kilograms compared to other designs. A wide range of fibers may be used, but those which reduce weight while retaining strength and toughness often increase the price significantly—e.g., a premium of 1000 Euros to save 3 kg. In addition, it is often hard to segregate and recycle the FRP materials. But despite the cost and other issues, the aerodynamic and weight advantages mean that (as of 2017) monocoque FRP is a common way to build velomobiles.
As of 2017, most velomobiles are tricycles with two front wheels. A tricycle has the advantage over a bicycle that it does not fall over when stopped. In addition, when a cross-wind hits a fairing, it makes a big force; faired tricycles are less likely to get blown over than faired bicycles. Although three wheels have practical advantages, they also have more aerodynamic drag than two wheels, so land speed record cycles are often bicycles. Although four wheels were used as far back as the Velocar, they are not today common. As of 2017, there is at least one 4-wheel production model, the QuattroVelo. Four wheels tends to further hurt aerodynamics and weight compared to three; but for a given width, four wheels is much more laterally stable than three wheels. Also, four wheels can be placed in a way that increases luggage capacity a lot compared to three-wheel designs.
Most velomobiles drive the rear wheel(s). This approach is simple and can often use many standard bicycle parts. Velomobiles with two rear wheels may drive just one wheel, or may drive both. Driving a single wheel is the simplest and lightest approach. Driving both wheels can improve traction but also increases complexity, cost, and weight. A solid axle may be used, but increases friction/drag in corners and thus can slow down the vehicle. One alternative is a differential, which is the approach used in most cars. A second alternative is to use a pair of ratchets, where the slower wheel is driven and the faster wheel coasts. Rear drive often uses "idler" pulleys to route the chain; front-wheel drive can eliminate idlers, so offers less friction and also less weight. It can also increase luggage capacity. However, front drive with two front wheels uses some non-standard components, and as of 2017 is used only rarely.
As with other cycles, a velomobile may use suspension. Suspension tends to improve rider comfort, and can also improve speed—it takes energy to "bounce" the velomobile and rider, so a suspension can reduce the energy lost to bouncing. However, suspension adds cost, weight, and maintenance. Common velomobile designs include no suspension, front-only suspension, and front+rear suspension.
As of 2017, there are several commercial makers of velomobiles. At the same time, there are still many "one-off" makers. Individual designs (both one-off and production) emphasize specific features. For example, some emphasize aerodynamics and light weight to improve average speed, even if cost, ease of entry/exit, comfort, and other "practical vehicle" attributes are reduced. By analogy, many automobile makers make performance cars with limited seating and cargo and worse emissions and fuel economy. In contrast, other velomobile designs sacrifice performance features in order to improve cost, entry/exit, comfort, carrying capacity, and so on. By analogy, many automobile makers offer cargo vans. As of 2017, individual makers sometimes offer models spanning a range of features—for example, there are Milan models used in racing but also a Milan "cargo" model with enough luggage volume to carry a (not-pedaling) human passenger and other bulky items.
All current (2017) velomobiles are produced in low volume, with "big" makers producing one or a few velomobiles per week. Velomobiles use some standard bicycle parts, but also many parts specific to velomobiles, and thus made in low volume. The use of "more parts" (e.g., 3 wheels instead of 2) and "more low-volume" parts makes velomobiles more expensive. The only attempt at a mass-produced velomobile, which was in the mid-1980s, flopped. This was the Sinclair C5. The C5 was a delta trike (one front, two rear wheels) with electric assist designed to be mass-produced and sold for a low price. The C5 was poorly designed; it was heavy, had only one gear and had no adjustment for the distance between the pedals and the seat, which is important to get a comfortable pedalling position.
A concept and a potential assessment concerning low-cost velomobiles for daily short trips as well as strategies for reaching a critical lot size for mass production was the subject of a research project called RegInnoMobil.Research project "RegInnoMobil" about low-cost velomobiles for short daily trips Retrieved on 19 January 2010.
Racing
Velomobiles have also been used in Australian HPV Super Series since 1985, and more recently, other events in Australia like the RACV Energy Breakthrough, the Fraser Coast Technology Challenge, and the Victorian HPV Series.