Page 796 - Automotive Engineering Powertrain Chassis System and Vehicle Body

Automotive instrumentation and telematics C HAPTER 23.1

The average fuel cost per mile C can be found by user speaks. There are two major categories of speech
calculating recognition software: speaker dependent and speaker
independent.
C ¼ðD P =MPGÞ fuel cost per gallon Speaker-dependent software recognizes the speech of
a specific individual who must work with the system. The
There are many other useful and interesting opera-
tions that can be performed by the variety of available user is prompted to say a specific digit a number of times
until the software can reliably identify the waveform
systems. Actually, the number of such functions that can patterns associated with that particular speaker. By this
be performed is limited primarily by cost and by the process, the system is ‘‘trained’’ to the individual user. It
availability of sensors to measure the required variables.
may not be capable of recognizing other users to whose
speech it has been trained.
Speaker-independent voice recognition software can
23.1.15 Telematics
recognize spoken digits regardless of the user. It is gen-
erally more sophisticated than speaker-dependent speech
Communications to and from an automobile has become recognition.
routine as a result of both cell phone and satellite tech- The cell phone connection can also be used to provide
nology. In addition, the technology is evolving for area online navigation or other services by contacting a service
broadcast of road condition information on radio station with operators trained to provide this type of service.
subcarriers. Technology is also evolving that will permit Alternatively, the cell phone can be used to provide an
Internet connections via cell phones, making the car in internet connection to an on-line navigation service that
effect on Internet node. Automobile Internet connec- transmits data to the car for display on an electronic
tivity opens a limitless range of services for the driver, map.
from on-line navigation help to on-line diagnostic and/or The telematics technology is presently in its infancy
road service for mechanical problems. and is certain to grow spectacularly in capability and
One of the major issues in telematics is how to present flexibility, providing the motorist with virtually limitless
the information and services that are potentially available
services. Telematics functionality is probably limited
to the driver without distracting from the driving tasks.
more by imagination than by technology.
Of course, the various services can be made available
to passengers without necessarily distracting the driver.
For example, video monitors in rear seats can provide 23.1.16 Automotive diagnostics
entertainment, game playing on any standard computer
Internet terminal via on-board DVD, or wireless con- In certain automobile models, the instrumentation com-
nection, be it cell phone or satellite links. puter can perform the important function of diagnosis of
On the other hand, the use of any subsystem that the electronic engine control system. This diagnosis takes
provides information such as is described above is place at several different levels. One level is used during
potentially distracting to the driver. The simple act of manufacturing to test the system, and another level is
dialing a standard cell phone requires the use of at least used by mechanics or interested car owners to diagnose
one hand and at least a momentary look at the cell phone. engine control system problems. Some levels operate
Some state legislatures are passing laws prohibiting the continuously and others are available only on request from
driver’s use of a standard cell phone while driving. an external device that is connected to the car data link for
The driver’s distraction through cell phone use is diagnostic purposes by a technician.
somewhat alleviated by voice-activated cell phone dialing In the continuous monitor mode, the diagnosis takes
in which the cell phone user verbally gives the phone place under computer control. The computer activates
number, speaking each digit separately. Included within connections to the vehicle sensors and looks for an open-
the cell phone is a very sophisticated algorithm for or short-circuited sensor. If such a condition is detected,
recognizing speech. Speech recognition software iden- a failure warning message is given to the driver on the
tifies spoken words or numbers based on patterns in the alphanumeric display or by turning on a labeled warning
waveform at the output of a microphone into which the light.

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