You may meet airport assistants Heather, Emily and Carla, or any number of their co-workers, in terminals across the globe.These charming ladies are on hand to help you with your travel needs, anything from directions and security regulations to liquid restrictions and boarding card details -- the kind of things that can often baffle infrequent fliers.But there is one difference to these helpers – they are virtual assistants, life-sized projections that are being rolled out at airports from Azerbaijan to the US in a bid to help travellers make their journeys more efficient.By using the latest in rear-projection technology, a high resolution, colour 3D-like holographic image is projected onto a flat two-dimensional sheet of acrylic in the shape of a woman. The life-like digital avatar is placed in key points around the airport, such as just before security, and reads out pre-recorded messages covering a variety of common topics.“The uniqueness of the hologram has really caught the attention of many of our new passengers, especially families,” said Nicola McCabe, head of customer service at East Midlands Airport in the UK.Some of the avatars have a sensor that activates the messages when someone is close by, others repeat their pre-programmed speeches on a loop. They’re designed to calm travellers’ nerves with a comforting yet informative voice, can speak multiple languages if necessary (some US airports program theirs in both Spanish and English, for example) and don’t need time off to go to the bathroom.New York’s Newark, JFK and LaGuardia airports have rolled them out, as has Boston’s Logan, Washington, DC’s Dulles and Azerbaijan’s Baku airport. A number of European airports have trialled the avatars too, including Paris’ Orly and the UK’s East Midlands, Edinburgh and London City.“We have had great feedback from our passengers,” said McCabe, “Ensuring that they were positioned in the right location to benefit passengers was something that had to be tried and tested. We now believe that they are in the correct place to engage with passengers before they proceed through security.”Virtual border guards are also being tested, with the US Customs and Border Protection trialling a kiosk at Dennis DeConcini Port in Nogales, Arizona, a border crossing between the US and Mexico. Called AVATAR (Automated Virtual Agent for Truth Assessments in Real-Time) and developed by the US government and the University of Arizona, an official figure (a man nicknamed Elvis) projected onto a screen conducts the interviews and can detect small changes in movement and behaviour to see if a traveller is telling the truth.The system uses three sensors to assess responses: an infrared camera that can detect pupil dilation and where the eyes are focusing; a high-definition camera to pick up changes in facial expression; and a microphone that analyses the pitch and frequency of the voice. Travellers stand in front of the kiosk to answer the yes or no questions, and if any unexpected physiological responses are picked up by the detectors then the person is passed on to a real border guard who conducts a more intensive interview.At Munich Airport a virtual assistant of a different kind is being introduced. Called InfoGate, passengers use an interactive screen to talk to a member of the airport information team via a live videoconference. The centrally-located team can link into any of the six booths located around the airport and answer questions immediately on all aspects of travel. During the conversation, both passenger and staff see each other as life-sized screen images in real time.