Requirements for A Multi-Component Communication System
A multi-component communication system consists of a collection of techniques, aids, symbols, and strategies in which the individual can use interchangeably depending on the individual's context, skills, communication partners, needs, etc. In order to be considered an optimal communication system, a multi-component communication system must fulfill certain requirements. The following is a brief list of the most important requirements that the communication system must fulfill in order to be effective. (The list was based on Chapter 3, page 54 in the text Augmentative Communication, An Introduction)
1. Provides All Communication Functions
All communication functions including basic needs, conversational needs, writing, drawing, and computer access must be fulfilled in order for the system operator to have the ability to communicate to his or her maximum extent. For instance, the individual must be able to tell someone they are hungry, carry on a typical conversation, print out a homework assignment, draw a picture, and hook up his or her system to a computer.
2. Compatible with Other Life Aspects
The multi-component communication system must also be compatible with the user's seating system, such as a wheelchair. It must not interfere with any environmental controls the individual may need to operate the controls in his or her home. Finally, the AC system must not interrupt the user's mobility in any way.
3. Unrestricted Communication Partners
The augmentative communication user must be able to communicate with not only people familiar with his or her device, but also with strangers. The system must be useable in group settings, classroom settings, and face-to-face conversation. Likewise, it is necessary for the system to incorporate an obvious yes/no that may be seen at a distance.
4. Useable in All Environments
The multi-component communication system must be useable in harsh and noisy environments. Similarly, the user must be able to operate the system at work, school, home, church, and in an unlimited amount of contexts.
5. Unrestricted Vocabulary
The individual using the communication system must be able to say any word, phrase, sentence, or idea he or she wishes. Therefore, the system must incorporate an unlimited vocabulary.
6. Most Effective Communication Possible
The communication system must operate at its maximum rate possible without fatiguing the user. The system must incorporate functions for the user to convey basic needs and yes/no answers at a distance. It must be interruptable and incorporate the ability to express emotions as well as words.
7. Promotes Growth
The augmentative communication system must promote growth in vocabulary, grammer, and topics for the user.
The communication system must be easy to use, as well as aesthetically pleasing in order to increase motivation by the user and his or her communication partners.
The price of the system must be affordable for the user, along with low maintenance.
Three Main Components of the Augmentative Communication System
The augmentative communication system is very complex and incorporates a variety of symbols, transmission techniques, vocabulary, strategies, and messages. However, the augmentative communication system may be broken down into three main components: human/technology interface, processor, and activity output. The following sections discuss these basic components in more detail.
1. Human/Technology Interface
The human/technology interface represents the interaction between the human user and the assistive technology. In an augmentative communication system, the human/technology interface is further broken down into a control interface, selection method, and selection set.
The hardware that the augmentative communication user accesses the device with is referred to as the control interface. The control interface selected for an augmentative communication user to interface with the AAC device is based on the most functional anatomical sites available. Augmentative communication devices are most commonly operated using a standard keyboard, a joystick, a switch, or a multiple switch arrangement. However, actual physical contact is not always necessary to access a communication device. Eye gaze and voice recognition are two examples in which the need for physical contact is eliminated.
The selection method refers to the way the augmentative communication user selects items from a selection set. There are two general types of selection methods: direct selection and indirect selection, or scanning.
The part of the augmentative communication device that displays a collection of symbols and/or vocabulary to the user is called the selection set. Symbols are something that stands for or represents something else. Symbols may be divided into two types - aided and unaided. Aided symbols require some type of external device (e.g. communication board, pencil, paper) for use. Unaided symbols require no type of external device (e.g. facial expressions, gestures, ASL) for use. There are numerous aided and unaided symbol systems that exist, as well as combinations of both.
The second main component of the augmentative communication system is the processor, which refers to the specialized techniques that are used to increase the rate or accuracy of messages. The processor is further categorized into components of rate enhancement and vocabulary expansion, vocabulary storage, and text editing.
3. Activity Output
Activity output is the third main component of the augmentative communication system that transmits the message to the communication partner. Visual display, voice, and print are the three types of activity output.