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TWIKE History & Technology The TWIKE is a human-electric hybrid vehicle (HEHV) / light electric vehicle (LEV) designed to carry two passengers and cargo. It can be driven in electric-only mode or electric + pedal power mode. A human-electric hybrid vehicle is a hybrid vehicle whose drivetrain consists of a human being and an electric motor/generator (and one or more electricity-storage device(s) such as a battery(ies) or ultracapacitor(s)). It has characteristics of a bicycle or velomobile with the addition of faster acceleration and regenerative braking, allowing a cyclist to stop and go through traffic signals and hilly terrain at a higher average velocity. In addition, a human-electric hybrid vehicle will typically have a clutch and at least three wheels, allowing the operator to continue pedalling and charge up the electricity-storage device during traffic stops in preparation for a faster departure. Because the electric motor provides assist during starts and hill-climbing, the human portion of the drivetrain can be much simplified from that of a traditional (muscle-powered) multi-speed bicycle or velomobile- it may have only one gear. 
Pedaling extends the range of the vehicle but does not substantially add to the vehicle's top speed. The vehicle cannot be driven solely by using pedal power. Regenerative antilock braking captures energy from deceleration to recharge computer-controlled batteries. The TWIKE, constructed of lightweight materials (like aluminium and plastic), this 246 kg (542 lb) (unladen) tricycle vehicle uses a 336 volt, 3.3 kilowatt-hour nickel-cadmium battery or a 6 kilowatt-hour nickel metal hydride battery and 3 kilowatt electric motor for primary power to the drivetrain. The battery can be fully recharged from a common 230V house outlet in 1.5 to 2 hours (NiMH: 3 hours). Additional energy is reclaimed while driving through regenerative braking, and load is removed from the electric system by use of the pedalling system which transfers its input directly to the drivetrain (ie, both systems operate in parallel, not in series). TWIKE owners, who often refer to themselves as TWIKE pilots, host periodic gatherings and tours in Europe and the United States to popularize the vehicle and celebrate its driving experience, which enthusiasts describe as an entertaining form of cardio-vascular exercise. Hosted primarily by the TWIKE KLUB organizations in Switzerland and Germany, such events have included rallies and tours of Europe and the U.S.
Method of Operation
In motion, the TWIKE is controlled using a single joystick, more akin to the tiller on a sailboat than a computer 'drive-by-wire' joystick. It is generally capable of speeds up to 85 kilometers per hour (53 mph). Fully charged, the vehicle is capable of travelling between 40 and 90 kilometers (25–55 miles) per charge on the NiCd batteries, and up to 90 miles (140 km) per charge on NiMh, depending on terrain, speed, driving style, weight of passengers and cargo, and of course the amount of pedaling by the pilot and passenger. The TWIKE's on-board computer controls all aspects of battery charging, discharging and power utilization. Modification of user-controllable system parameters can significantly affect performance, yielding faster or slower acceleration and longer or shorter ranges (American TWIKE enthusiasts have reported achieving speeds in excess 105 km/h (65 mph)). Cost of OperationIn the United Kingdom, a kWh of electricity costs between 3 and 15 pence (average: 7 pence), meaning a full charge of a standard two-battery TWIKE would cost about 21-31 pence. In the United States, a a kWh of electricity costs generally 10 cents, subject to change, meaning a full charge would cost 30 to 45 cents. As with all electric vehicles (EVs) the price of battery replacement cannot be ignored as they will need to be replaced. Total cost of ownership per mile is a more accurate comparison to a typically fueled vehicle rather than the amazingly cheap 'fill-up' cost, but also includes other factors such as license & registration fees, parking fees etc. that are very specific to each owner/application. 
One of the most expensive and critical parts of an EV are its batteries, and they have to be periodically replaced depending on numerous factors such as age, battery care (how they were charged/discharged, what temperature they were stored at) as well as the number of charging cycles. Depending on single-charge range requirements and how different battery types operate near their end-of-life, reduced range may not necessitate replacement allowing the batteries to be used past the maximum charging cycles listed (ie, if new batteries can take you initially 40 miles a charge, and the batteries are listed as max 1500 charging cycles, that's 1500 charging cycles at full 40 miles range. But if you only drive 5 miles between charging stations, as long as the batteries can go 5-8 miles per charge you may be able to get quite a bit more than 1500 charging cycles). Selection of the battery chemistry (Lead-Acid, NiCad, NiMH, Li-ion, Li-pol) is a trade-off based on the qualities of the battery: Deep Cycle (Marine or RV) Lead-Acid batteries are the most often in EV's, since they are fairly rugged, require little care, cheap and readily available. The trade-offs are they take a long time to charge and have one of the lowest (worst) energy to weight ratios. Simply put, they don't go as far. Most Lead-Acid based EV's require charging times of 8 hours or more (overnight) for a full charge. NiCad and NiMH have shorter charge times (2 hours for a full charge for a Twike at European 230V/16A) and therefore allow for quick partial charges for when you underestimate how far you are from your normal charging destination and need to grab a quick get-me-there charge on the road. They are also significantly more energy dense (energy/weight ratio) than Lead-Acid. The trade-off is that they are more expensive, less easily acquired and require more careful care. Each battery chemistry also comes with its own drawbacks and it behooves the EV owner to become familiar with battery technology prior to purchase or ownership. See http://www.powerstream.com/BatteryFAQ.html Calculations made from data from the UK Twike site (http://www.twike.co.uk) on August 6th, 2007. Monetary conversions to US$ on August 28, 2007 NiCd, 2 x 3.6Ah - max 40 miles, max 1500 charging cycles, cost £3,180 (US$ 6,371) - will cost £2.12 (US $4.25) per cycle or 5.3 pence (US $0.11) per mile at best driving - will last between 30 and 60.000 miles NiCd, 3 x 3.6Ah - max 55 miles, max 1500 charging cycles, cost £4,270 (US$ 8,555) - will cost £2.84 (US$ 5.69) per cycle or 5.2 pence (US$0.10) per mile at best driving - will last between 45.000 and 82.500 miles NiMH, 2 x 8.9Ah - max 90 miles, max 700 charging cycles, cost £6,980 (US$13,984) - will cost £9.97 (US$19.98) per cycle or 11.1 pence (US$0.22) per mile at best driving - will last between 35.000 and 63.000 miles Availability for PurchaseOriginally developed in Switzerland, the TWIKE is now manufactured in Germany by FINE Mobile GmbH and may be driven on public roads by drivers with a full driving license. In the United States, there are fewer than 10 TWIKES currently in operation.[1] The Twike is registered with the US DOT as a motorcycle, and thus is legal to import or to drive anywhere motorcycles may be ridden. This is a Federal designation, which applies in all 50 of the United States. Import to Canada and Mexico is possible, pending government approval in those countries or an equivalent NAFTA ruling. The 2007 Neiman Marcus® Christmas Book offers the TWIKE for sale. The NM® exclusive edition features a sporty British racing green exterior to balance its silver-grey interior, velour carpeting, and leather seats. ($40,000; page 89) Normal pricing for a TWIKE is between 17.800 € to 32.200 €, depending on the model chosen. History
 More than 750 TWIKES have been sold, most of them operating on the streets of Switzerland and Germany. They are also driven in the United Kingdom, Austria, the Netherlands, Italy, France, Spain, Belgium, and the United States. The TWIKE I was developed for the 1986 World EXPO in Vancouver / Canada by a group of Swiss students. It won the "Functionality Award" for the best ergonomic design in the Innovative Vehicle Design Competition (IVDC) and a first prize in the International Human Powered Vehicle Speed Championship . The TWIKE I was completely driven by human power. Inspired by the success of the TWIKE I, a group of enthusiasts including Ralph Schnyder and Peter Zeller began to develop the TWIKE II as a step towards a vehicle for everyday road use. It was developed in cooperation with Alusuisse-Lonza Services, has been shown on the HEUREKA exhibition in Zürich, and took part in the 1991 Tour de Sol Alpin. The TWIKE II featured a belt pedal drive with infinitely variable mechanical transmission and a DC motor powered by NiCd batteries to help propel the vehicle. The suitability for everyday use turned out to be significantly improved. In 1992, the newly founded TWIKE Ltd. decided to develop the TWIKE II into a production vehicle and began looking for capital and customers. Production of the TWIKE III began in 1995 and during 1996 the now reformed TWIKE AG produced and sold 190 vehicles, mostly in Switzerland and Germany. The TWIKE III was already equipped with an asynchronous AC motor and 336V NiCd batteries - the system that is still in use today. In 1998, FINE Mobile GmbH launched its German TWIKE production line and finally became the exclusive producer of the TWIKE after taking over the rights of the SwissLEM AG in 2002. Today the TWIKE is produced in Rosenthal, a small village in Hessen near Marburg. See also
External links
ReferencesThis article is licensed under the GNU Free Documentation License. It uses material from Wikipedia Encyclopedia article "Twike" |
