MDI ARCHIVES

HISTORY OF AIRPod 

Pictures from the unveiling of the AIRPod range - the AIRPod  AIRPod Cargo & AIRPod Baby

MDI AIR CAR - lifestyle, ecology, economy 

MDI's Compressed Air AIRPod

The AIRPod is one of five derivative vehicles designed by MDI based on its Compressed Air Engine (CAE) invented by Guy Nègre, CEO and founder of MDI. In 2007, MDI signed an agreement with Tata Motors for the application of CAE technology in India.

The core of MDI’s work is a piston engine powered by the expansion of electronically injected compressed air. MDI has developed two versions: a single fuel engine that relies solely upon compressed air, designed for urban areas only (e.g., AIRPod); and a dual-fuel version that uses compressed air and a combustible fuel (petroleum-based or biofuel). The compressor is onboard in the MDI vehicles, with the exception of the single-fuel AIRPod where it will be outboard but supplied with the car.

The MDI Engines consist of an active chamber and are made up of modules of two opposing cylinders. A proprietary connection rod allows the retention of the piston at top dead center during 70° of crankshaft rotation—providing enough time to establish the required pressure in the cylinder. These modules can be coupled to make groups of 4 or 6 cylinders for a range of uses from 4 to 75 hp.

• A range of low cost, high efficiency, zero emission vehicles, for private transport (including the small OneFlowAIR 3-seater urban model, the 3-seater MiniFlowAIR, the 6-seater CityFlowAIR — (formerly CAT - Compressed Air Transport), utility services (trucks, vans, etc.), public transport (minibuses and large buses), farm machinery, marine applications, and light aircraft applications.

• Being designed to have driving and safety performances similar or superior to existing vehicles in their respective classes.

March 19, 2007

   Many respected engineers have been trying for years to bring a compressed air car to market, believing strongly that compressed air can power a viable "zero pollution" car. Now the first commercial compressed air car is on the verge of production and beginning to attract a lot of attention, and with a recently signed partnership with Tata, India’s largest automotive manufacturer, the prospects of very cost-effective mass production are now a distinct possibility.

    The MiniC.A.T is a simple, light urban car, with a tubular chassis that is glued not welded and a body of fibreglass. The heart of the electronic and communication system on the car is a computer offering an array of information reports that extends well beyond the speed of the vehicle, and is built to integrate with external systems and almost anything you could dream of, starting with voice recognition, internet connectivity, GSM telephone connectivity, a GPS guidance system, fleet management systems, emergency systems, and of course every form of digital entertainment.

   The engine is fascinating, as is and the revolutionary electrical system that uses just one cable and so is the vehicle’s wireless control system. Microcontrollers are used in every device in the car, so one tiny radio transmitter sends instructions to the lights, indicators etc

    Most importantly, the 60 kph Air car is incredibly cost-efficient to run – according to the designers, it costs approx $2 per 100Km (about a tenth that of a petrol car). Its mileage is about double that of the most advanced electric car (200 to 300 km or 10 hours of driving), a factor which makes a perfect choice in cities where the 80% of motorists drive at less than 60Km.

MDI Air Car features

• The end product is a light weight vehicle that can reach speeds up to 110 kph.

• MDI's vehicle's have fibreglass bodies which makes them light, silent urban car. The car's body is tubular, light weight, and is held together using aerospace technology.

• The vehicles do not have normal speed gauges. Instead, they will have a small computer screen that shows the speed and engine revolutions. The system allows for infinite possibilities such as GSM telephone systems, GPS satellite tracking systems, programs for delivery people, emergency systems, internet connections, voice recognitions, map presentation, traffic information, etc.

• The seatbelt system is different from what we know. One part of the belt is anchored to the floor of the car, like traditional cars. The other part of the belt, instead of being attached to the side of the car, is also anchored to the floor of the vehicle. This helps to secure the bodies of the driver and passengers in the case of a collision.

• The vehicle's electric system is also revolutionary. MDI has bought a patent that is bound to reduce the important of electrical systems in all cars. The trick consists in using a small radio signal. The system makes the car 20 kilos lighter and considerably quieter.

• There are no keys - just an access card that can be read by the car from your pocket.

• In the single energy mode MDI cars consume around $3 every 100 km.

• When there is no combustion, there is no pollution.

• The recharging of the car will be done at gas stations, once the market is developed. To fill the tanks it will take about to 2 to 3 minutes at a price of $4 90. After refilling the car will be ready to driver 200 kms.

• There is the alternator motor on board, that is used in reverse mode to fill up at the mains (in at least 4 hours).

• Because the engine does not burn any fuel the car's oil (a litre of vegetable) only needs to be changed every 50,000 km.

• The temperature of the clean air expulsed form the exhaust pipe is between 0 and 15 degrees below zero and can be subsequently channelled and used for air conditioning in the interior of the car.

Compressed air tanks

   One of the most frequently asked questions is about the safety of the compressed air storage tanks. These tanks hold 90 cubic metres of air compressed to 300 bars. Many people ask whether this system is dangerous in case of an accident and if there is a risk of explosion. The answer is NO. Why? Because these are the same tanks used to carry the liquid gas used by buses for public transport. The tanks enjoy the same technology developed to contain natural gas. They are designed and officially approved to carry an explosive product: methane gas.

   In the case of a major accident, where the tanks are ruptured, they would not explode since they are not metal. Instead they would crack, as they are made of carbon fibre. An elongated crack would appear in the tank, without exploding, and the air would simply escape, producing a loud but harmless noise. Of course, since this technology is licenced to transport an inflammable and explosive gas (Natural gas), it is perfectly capable inoffensive and non-flammable air.

   It is fitting, therefore, that MDI has reached an agreement with the European leader in aerospace technology Airbus Industries for the manufacture of the compressed air storage tanks. With a remote supervision arrangement, Airbus Industries oversees the making of the storage tanks at each MDI factory. The coiled carbon fibre technology used in the construction of the tanks is complex and requires a substantial quality control process which the multinational company, home of the Airbus aircraft, will provide for our vehicles.

Brake power recovery

   The MDI vehicles will be equipped with a range of modern systems. For example, one mechanism stops the engine when the car is stationary (at traffic lights, junctions etc). Another interesting feature is the pneumatic system which recovers about 13% of the power used.

The body

    The MDI car body is built with fibre and injected foam, as are most of the cars on the market today. This technology has two main advantages: cost and weight. Nowadays the use of sheet steel for car bodies is only because of cost - it is cheaper to serially produce sheet steel bodies than fibre ones. However, fibre is safer (it doesn't cut like steel), is easier to repair (it is glued), doesn't rust etc. MDI is currently looking into using hemp fibre to replace fibre-glass, and natural varnishes, to produce 100% non-contaminating bodywork.

The Air Filter

   The MDI engine works with both air taken from the atmosphere and air pre-compressed in tanks. Air is compressed by the on-board compressor or at service stations equipped with a high-pressure compressor.

   Before compression, the air must be filtered to get rid of any impurities that could damage the engine. Carbon filters are used to eliminate dirt, dust, humidity and other particles which, unfortunately, are found in the air in our cities.

   This represents a true revolution in automobiles - it is the first time that a car has produced minus pollution, i.e. it eliminates’ and reduces existing pollution rather than emitting dirt and harmful gases. The exhaust pipe on the MDI cars produces clean air, which is cold on exit (between -15º and 0º) and is harmless to human life. With this system the air that comes out of the car is cleaner than the air that went in.

The chassis
   Based on its experience in aeronautics, MDI has put together highly-resistant, yet light, chasses, aluminium rods glued together. Using rods enables us to build a more shock-resistant chassis than regular chasses. Additionally, the rods are glued in the same way as aircraft, allowing quick assembly and a more secure join than with welding. This system helps to reduce manufacture time.

Electrical system

   Guy Nègre, inventor of the MDI Air Car, acquired the patent for an interesting invention for installing electrics in a vehicle. Using a radio transmission system, each electrical component receives signals with a microcontroller. Thus only one cable is needed for the whole car. So, instead of wiring each component (headlights, dashboard lights, lights inside the car, etc), one cable connects all electrical parts in the car. The most obvious advantages are the ease of installation and repair and the removal of the approximately 22 kg of wires no longer necessary. What’s more, the entire system becomes an anti-theft alarm as soon as the key is removed from the car. 

Here's a brief look at how the AIR Car (formerly CAV's - Compressed Air Vehicle) engine will run:

Low speeds: When the car is traveling 35 miles (56 km.) per hour or less, the engine runs only on air compressed to 4,500 pounds per square inch (31,028 kilo-newtons per square meter). The compressed air is stored in reinforced carbon-fiber tanks, which have a capacity of about 80 gallons (304 liters) and are attached below the chassis.

Higher speeds: When the driver accelerates above 35 miles (56 km.) per hour, the CAV's computers automatically kick on a small fuel burner positioned between the motor and the compressed air tank. Fossil or bio fuel will power that heater, but not through traditional internal combustion. Instead, the heat generated by the burning liquid fuel is the central element in generating greater speed. Heat automatically adds pressure to compressed air. So any boost in acceleration means higher pressure in the air that drives the engine's pistons. Voilà, more power.

Compressed air refills: Owners can generate a full tank of compressed air by plugging the car into a home socket. A recharge takes about four hours. Service stations may also offer compressed air refills, taking about three minutes to complete. The estimated cost of a full refill is less than $3.

CO2 emissions:icials, however, promise that the car will be put through all of the usual regulatory wringers. In the meantime, they're saying that there will be zero CO2 emissions at speeds of less than 35 miles per hour. Driven faster, the AIRCity will emit 2.52 ounces of CO2 per mile (4.41 grams per kilometer), according to MDI officials.

That's strikingly lower than the 1.192 pounds of CO2 per mile (333.8 grams per kilometer) that the average American auto puts out, according to data from the U.S. Department of Transportation. And the AIRCity CO2 output is also considerably less than the 6.58 ounces of CO2 per mile (115.2 grams per kilometer) that's emitted by Toyota's Prius Plug-in Hybrid. Source

Some Features of the AIRPod

• The AIRPod is not a car, but an urban "transporter" on compressed air. A certification as a car is not needed, and neither is a driver's license for use in Europe.

• “We have already identified keen demand for off-road applications of the AIRPod in the thousands of units throughout Australia, New Zealand and the Pacific”, said Dr Arnoux, “this gives us time to get through the certification processes in Australia and New Zealand for on-road applications.”

• It has no steering wheel, no dashboard nor pedals: you use the joystick for steering, braking and accelerating.

• It needs an "air station": unlike the other MDI models, it cannot be refilled by plugging it in the mains at home.

•  It has an external airbag under the floor, which opens when the emergency brake pedal is used this absorbs the kinetic energy of the crash outside the Pod. The Pod itself is made of composite materials that constitute a safe cell protecting the passengers

• These prototypes will be improved in the field of suspension, noise and drivability. The control buttons for the lights, the windscreen wipers, etc will be added to the joystick

• MDI intends to equip the side windows of the AIRPod with a hinge system permitting to open them in an awning way.

• The AIRPod's can be parked perpendicularly to the sidewalk, the one next to the other, as the access is through the windshield and the car is only 2 m long.

•  It has one engine, and differentiate the access to each rear wheel. This way the AIRPod can still rotate (no reverse gear?)

• The AIRPod's being prepared for Geneva Motor Show have rear view mirrors and headlights, also some new look and ergonomics.

• MDI announces that it is working on an air pump that will enable to fill up the compressed air tanks of your car at home in three minutes, at a price of 2,5 Euros.

• According to Australian IT MDI-Energy Ltd, a joint venture of MDI and IndraNet Technologies Ltd (New Zealand) there will be a dual energy version of the AIRPod. Adding a very small amount of biofuel an range of 360 miles will be reached.

• AirFrance-KLM is interested in the AIRPod's.. They will test them from spring 2009 during 6 months on the tarmac.

Photos by Nick Kurczewski

      One single front wheel               |                  Chain in carter                              |   Rear wheel with chain in carter             |       Aluminum chassis                   |     Rear light & indicator light