Speech Recognition and Synthesis

The application of speech recognition (SR) in aviation is rapidly evolving and moving toward more common use on future flightdecks. The concept of using SR in aviation is not new. The use of speech recognition and voice control (VC) has been researched for more than 20 years, and many of the proposed benefits have been demonstrated in varied applications. Continuing advances in computer hardware and software are making the use of voice control applications on the flightdeck more practical, flexible, and reliable. There is little argument that the easiest and most natural and ideal way for a human to interact with a computer is by direct voice input (DVI). While speech recognition has improved over the past several years, speech recognition has not reached the level of capability and reliability of one person talking to another. Using SR and DVI in a flightdeck atmosphere likely brings to mind thoughts of the computer on board the starship Enterprise from the science fiction classic Star Trek , or possibly of the HAL9000 computer from the movie 2001: A Space Odyssey. The expectation of a voice control system like the computer on the Enterprise and the HAL9000 computer, is that it be highly reliable, work in adverse and stressful conditions, be transparent to the user, and understand its users accurately without having to tailor their individual speech and vocabulary to suit the system. Current speech recognition and voice control systems are not able to achieve this level of performance expectations, although the ability and flexibility of speech recognition and its application to voice control has increased over the past few years. Whether or not a speech recognition system will ever be able to function to the level of one person speaking to another remains to be seen.