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6.9 Speech systems

The company Checklist Technologies developed a range of new Electronic checklists. For instance the EC-TS (Electronic Checklist-Text to Speech) displays text and turns the written text into speech. These devices leave the pilot "hands free". Besides very useful / safe in real life, this is also a very attractive functionality in a flight simulator cockpit. In general you will fly alone, no co-pilot ... only your PC. Besides the chance of feeling lonely, handling more complex situations / aircrafts can become less realistic due to an information overload. An automated checklist either in text only or in text-to-speech mode can be your solution. The same applies for the use of voice commands, if you need an extra pair of hands to fly the way you would prefer, this may be your solution.

6.9.1 Voice commands

By now there are very interesting solutions using voice commands. When used with Microsoft Flight Simulator it adds to the feeling that one is in the cockpit of an aircraft, giving instructions to a co- pilot.

Voice Buddy (eDimensional) is a combination of headset and software for speech recognition. Voice Buddy is among others prepared for the use with Microsoft Flight Simulator. It comes with interactive checklists for the stock aircraft. In addition to all the flight simulator commands, Voice Buddy also includes a collection of cabin announcements and cockpit standard operating procedure dialogs between pilot and co- pilot.

There is also an open source initiative SpeechBuddy that can be downloaded from AVSIM. It allows for speech recognition as an interface to Microsoft Flight Simulator. SpeechBuddy uses a scripting language that allows you to send keystrokes to Microsoft Flight Simulator, use the FSUIPC interface, play audio files or interact with the user using text-to-speech synthesis.

Currently the most advanced voice interaction is offered by VoxATC (VoxATC) provides a simulated ATC environment for FS2004 with integrated voice recognition. You are talking to the controllers and besides listening to your requests they check your read backs. Additional chatter is generated by intelligent agents that are either controllers or pilots currently in the airspace. VoxATC runs alongside FS2004 and replaces its native ATC.

6.9.2 Speech synthesis

Voice can add serious value to your simulator experience. A "talking" checklist or "talking" warnings can reduce the information overload in the cockpit, making it more realistic (or more fun) to fly more complex aircrafts. There are several commercial products around that add a "digital" co-pilot to the Microsoft Flight simulator.

A ready to use example is FS Hotseat (FSHhotseat). It facilitates the addition of sound with a predefined sequence of events, also it introduces a co-pilot who will read configurable checklists. An other example is FDC Live Cockpit (Oncourse Software). It adds realism by providing a host of audio enhancements which include full cockpit crew, cabin attendants, general ambience, and ATC chatter. Additionally it is possible to have your co-pilot perform various duties by turning on the Virtual Co- pilot mode. A similar product is FS Flight Keeper (Thomas Molitor).

A real "Bitchin Betty" as you find in a fighter jet is provided by FS Voice Message System (Rogers). You can use FS VMS to hear voice warnings when certain flight parameters are exceeded. Parameters can be set for altitude, angle of attack, bank angle, g-force, gear speed, ground proximity, ground speed, indicated airspeed, turn rate, turn coordination and vertical speed. These parameters can be set differently for the various phases of flight such as taxi, climb, cruise, maneuver, descent and approach. Also included is a flight logging feature which, among other things, includes descriptions of exceeded parameters in chronological order.

The downside of the above listed software packages is that they work based on real sound bytes. Only within a fixed framework a voice can be added / applied. If your ambitions are (a bit) higher, it is possible to develop your own digital co-pilot. During recent years developments with respect to speech generation reached the level that with moderate effort one can develop a text-to-speech software application.

For programmers the starting point is the Microsoft text-to-speech support (example on Coding4Fun). Starting with Windows XP Microsoft included a text to speech generator by default.

There are also commercial libraries that can be included with e.g. a Visual Basic program, the use of these libraries is often a bit easier than using the SDK. An example is TR Speaker component (Text-reader) which is an ActiveX control that adds text-to- speech capabilities to an application. This control aggregates the Microsoft Direct Speech Synthesis control (DirectSS). An other example is Speech Kit (Chant) that provides a text-to-speech library and also supports the .NET framework. This library provides your application a simple way to develop software that speaks by handling the low-level functions with text-to-speech engines.

If you are not deep in to software development, then there are even hardware solutions available. For instance DoubleTalk [Triangle Digital] which stands for a series of devices that can be connect to a PC by means of an ISA slot or serial interface. Using a dedicated text-to- speech chip it translates plain English text into speech in real time. Functionality that is included is unlimited vocabulary, on-the-fly voice control, tone generation, recorded audio playback, addressable voice channels, multiple input and output protocols, etc. A board level solution is TextSpeak [Digital Acoustics] that accepts RS232 input and provides a natural voice with unlimited vocabulary.