The robotically driven vehicles could save billions each year in fuel. The demonstrator vehicle weighs 52 tonnes and is powered by twin, 500hp V8 diesel engines which operate a complex hydrostatic drive system as well as hydraulic systems handling the 4-wheel steering and aircraft pick-up and clamp actuators.
Once this testing is completed it is planned that the demonstrator vehicle will be shipped to Toulouse airport where the TaxiBot will be used in further tests in February 2010 with an Airbus owned A340-600 airplane weighing approximately 350 tonnes. The Ricardo team on the TaxiBot programme will continue to support the development work throughout this next phase based at Toulouse.
The demonstrator, a six-wheeled vehicle, is capable of towing Boeing 747 and Airbus A340 airliners.
The Taxibot is based on a Krauss Maffei PTS-1 aircraft towbarless tractor that has been redesigned, modified and rebuilt by Ricardo to install IAI’s idea of a turret and energy absorption systems and controls.
On engaging with the TaxiBot, the nose wheel of the aircraft enters the vehicle turret that can rotate freely and hence take steering and braking requests directly from the nose wheel.
With the TaxiBot engaged the flight, crew can manoeuvre the aircraft around the taxi-ways of the airport, relying solely on auxiliary power units for on-board power and air conditioning needs.
The towing vehicle has the potential to reduce fuel costs and emissions, since at present aircraft taxiing to and from the airport terminal gate and runway is a major source of CO2 emissions, fuel consumption.
Ricardo has been involved in the project for IAI for 15 months and in June 2009, IAI and Airbus signed a memorandum of understanding for development of the Taxibot concept.
At present, the prototype assumes an operator in the vehicle, however, the control architecture of the vehicle allows for autonomous tug operation, so in future no tug driver would be needed for taxiing.
IAI’s Taxibot is a a tow-bar-less robotic tractor that would allow both wide and narrow body commercial airplanes to taxi to and from the gate and the runway without using their jet engines, while remaining under full pilot control at all times and removing all hazards to ground vehicle drivers. Unlike systems like Wheeltug, the system requires no modifications to airliner fleets. It does share the advantage of letting the pilot move and steer the aircraft on the ground, using the same controls and motions they’ve been trained to use during full engine maneuvers.
The Taxibot demonstrator is currently powered by 2 diesel engines, which drives 6 hydraulic motors in a typical “one in each wheel” hydrostatic drive architecture. For the prototype and serial production, IAI says that other hybrid electric solutions will be considered.
EADS and IAI report that an initial evaluation of this concept has shown promising results. IAI believes “Taxibot” could reduce annual fuel costs from $8 billion to less than $2 billion, CO2 emissions from 18 million tons to less than 2 million tons per year, and noise emissions by a significant margin. That last component is a less attention getting environmental component, but its significance will rise. The US Department of Transportation-led study “Trends in Global Aviation Noise and Emissions from Commercial Aviation for 2000 to 2025″ predicted that despite noise level improvements in next-generation airplanes, the number of people forced to deal with serious aircraft noise will rise from 24 million in 2000 to 30.3 million by 2025.
A June 2009 Memorandum of Understanding between IAI and EADS aims to take the next steps, and validate Taxibot’s potential. Airbus will participate in the feasibility studies, using an Airbus-owned A340-600 long haul airliner as the test subject. In addition to the ground tests in Toulouse, France, the MoU assessment phase will also cover regulatory, legal/product liability, environmental, and financial evaluations.
If all goes well during those 2009 assessments and subsequent operational demonstrations, IAI and EADS would look to a 3-way partnership with a vehicle manufacturer, in order to certify, produce, and sell Taxibot tractors to airports. Under current plans, Taxibot would be ready for first deliveries by the Q3 2011.