Classifications

• • G—PHYSICS
  • G08—SIGNALLING
  • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
  • G08B21/00—Alarms responsive to a single specified undesired or abnormal condition and not otherwise provided for
  • G08B21/02—Alarms for ensuring the safety of persons
  • G08B21/06—Alarms for ensuring the safety of persons indicating a condition of sleep, e.g. anti-dozing alarms
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
  • B60K28/00—Safety devices for propulsion-unit control, specially adapted for, or arranged in, vehicles, e.g. preventing fuel supply or ignition in the event of potentially dangerous conditions
  • B60K28/02—Safety devices for propulsion-unit control, specially adapted for, or arranged in, vehicles, e.g. preventing fuel supply or ignition in the event of potentially dangerous conditions responsive to conditions relating to the driver
  • B60K28/06—Safety devices for propulsion-unit control, specially adapted for, or arranged in, vehicles, e.g. preventing fuel supply or ignition in the event of potentially dangerous conditions responsive to conditions relating to the driver responsive to incapacity of driver
  • B60K28/066—Safety devices for propulsion-unit control, specially adapted for, or arranged in, vehicles, e.g. preventing fuel supply or ignition in the event of potentially dangerous conditions responsive to conditions relating to the driver responsive to incapacity of driver actuating a signalling device

Definitions

• This invention relates to a driver alertness monitor for measuring time taken by a driver to react to a stimulus generated while driving and comparing the measurement with a standard thereby to indicate the state of alertness of the driver.
• driver includes any person who is in control of land based or water or air borne transport.
• an alertness monitor comprising means for calibrating reaction time of a human subject in normal conditions to provide a standard, means for measuring reaction time of the subject when carrying out an activity and means for comparing the measured reaction time with the standard and for generating a warning signal when the measured reaction time is greater than the standard.
• the monitor disclosed in WO 93/08739 adapts to the individual subject under test, the stimulus is presented at random intervals and there is no provision for taking into account whether the individual whose reaction time is tested subsequent to calibration is already in a state of alertness. If such a monitor were to be used to test the reaction time of a driver of a motor vehicle, for example, it cannot be assumed that the driver would welcome receiving random stimuli when in a state of alertness.
• the invention is characterised in that there is provided a control means for controlling intervals of measuring reaction time so that measurement is carried out more frequently when deterioration of reaction time is determined and less frequently when the reaction time is less than the standard.
• the invention thus provides a driver alertness monitor which becomes more sensitive as the driver's performance capability deteriorates but not being an irritating intrusion while the driver is alert.
• the invention also provides a driver alertness monitor which monitors the driving performance capability of the driver and which provides information indicative of the performance so that the driver may make an informed decision.
• the invention will test and compare to a standard or previous calibration and then decide how best to modify the test interval.
• the monitoring of the driving performance capability is effected by means, in accordance with the invention, operation of which does not adversely affect the driver's control of the vehicle and operation of which can be effected by the driver in any hand position of hand control means while controlling the vehicle.
• the invention also provides a facility for interactivity with the driver and for diurnal variation, in particular for increasing sensitivity for periods of a twenty four hour cycle when a driver is less likely to be in a state of alertness.
• FIG. 1 is a general arrangement of one embodiment of a driver alertness monitor in accordance with the present invention
• Figure 2 is a flow diagram indicating a method of calibration in accordance with the present invention
• FIG. 3a and 3b together comprise a flow diagram indicating a method of testing driver alertness in accordance with the invention
• Figure 4 is a diagrammatic representation of information as would appear on a coded light box and on an alphanumeric display of the monitor.
• Figure 5 is a diagrammatic cross section of an embodiment of a manually operable transducer in accordance with the invention.
• FIG. 6 is a diagrammatic representation of another embodiment of a transducer in accordance with the present invention.
• Figure 7 is a diagrammatic representation of another embodiment of a transducer in accordance with the present invention.
• a driver alertness monitor in accordance with the present invention comprising a central processing unit 1 located in a motor vehicle and having connected thereto a transmitter/receiver 2, and an audio amplifier 3 controlling a speaker 4.
• the transmitter/receiver 2 is adapted to communicate by cableless data transmission using ultrasonic, IR or RF signals with a coded light box 5 and an alphanumeric display 6, both included in or being located adjacent an instrument panel of the vehicle, and a transmitter 7 carried on a steering wheel 10 of the vehicle and operated in response to signals received from a transducer 9 in the form of a steering wheel cover and being operable when squeezed by a driver 8.
• the arrangement is such that, when an audible stimulus is generated by the speaker 4, the driver responds by squeezing the steering wheel cover thereby operating the transducer 9.
• Such operation of the transducer 9 results in a signal being transmitted from the transmitter 7 to the transmitter/receiver 2 and the reaction time from generation of the stimulus to operation of the transducer 9 is calculated by the central processing unit 1.
• An indication of the reaction time is then provided by the coded light box 5 and the alphanumeric display 6 as a result of signals received from the transmitter/receiver 2.
• transducer 9 extends through 360° around the steering wheel, operation of the transducer can be effected without either hand of the driver being removed from the steering wheel in any position and the operation is effected while controlling the vehicle.
• the transducer 9 is also in communication with the central processing unit 1 to monitor the level of hand activity of the driver 8 on the steering wheel 10.
• FIG. 2 there is shown flow diagrams indicating control carried out by the central processing unit 1 including means to GENERATE A STIMULUS, more particularly the audible signal from the speaker 4, and means to MEASURE REACTION TIME consequential upon the driver operating the transducer 9 in response to the stimulus.
• a system for effecting calibration is indicated in Figure 2 whereby an initial step is carried out to CALCULATE AVERAGE REACTION TIME AND STANDARD DEVIATION.
• a predetermined series of measurements of reaction time is taken at the end of which ENOUGH REACTION TIME READINGS have been recorded.
• An initial screening process is carried out in respect of each test result by interrogating IS RESULT SENSIBLE? If the response is negative because the reaction time is outside of a predetermined range of reaction times, the erroneous reading is rejected and the process is repeated after a SHORT DELAY.
• the procedure described above will be abbreviated if the driver's reaction time has already been calibrated and the information stored in the system. In such circumstances, the driver would operate the system to USE PREVIOUSLY OBTAINED CALIBRATION. It may be that the store would include a facility for storing reaction times of a plurality of drivers and in such circumstances the system would be operated to SELECT DRIVER AND RELEVANT PARAMETERS.
• the system subsequently would CALCULATE RUN TIME PARAMETERS and is then in a ready state for testing driver alertness during a journey.
• a test for reaction time is carried out. Preferably this would be an average of a series of tests taken in rapid succession rather than a single test. This would ensure that the driver is not starting out in a condition unfit for driving. If the last produced test result is consistent with a previous stored calibration, the stored data would be used.
• a system for testing driver alertness during a journey is indicated in Figure 3a and 3b wherein the system would GENERATE A STIMULUS and would MEASURE REACTION TIME when the driver operates the transducer 9 in response to the audible stimulus from the speaker 4.
• the reaction time is screened by interrogating IS RESULT SENSIBLE?, for example, within a predetermined range of 150 ms to 750 ms.
• the system Apart from determining when next to test the driver, the system also monitors driver hand activity on the steering wheel 10 and, when there is little activity, is adapted to test the driver reaction in abnormal circumstances. In any event, the system ensures, as far as possible, that tests are carried out when the interrogation IS DRIVER BUSY? is answered in the negative, ie when there is little hand activity of the steering wheel 10. If the driver is busy, A SHORT DELAY will be initiated before a succeeding stimulus is generated.
• reaction time is within the predetermined range an indication is provided on the coded light box 6 and the alphanumeric display 7, the data indicated being as shown in Figure 4.
• REACTION TIME is IN BAND 1, ie 150 ms to 300 ms, an indication is provided as a double green light in box 5 and "Excellent" in the display 6 and since the reaction time would be an improvement on the calibration figure and the system responds to INCREASE DELAY TIME and DECREASE REACTION TIME AVERAGE whereby the interval between generation of successive stimuli is increased.
• the reaction time is satisfactory and an indication is provided as a green light in box 5 and "Good" in the display 6 and the situation is such that the SYSTEM AND DRIVER are STABLE, as a result of which the interval between generation of successive stimuli is unaffected.
• reaction time fails to improve and a MAXIMUM NUMBER OF RETRIES, eg four, are EXCEEDED a flashing red light appears in box 5 and "STOP DRIVING NOW" in the display 6 and an ALARM is sounded.
• the visual display for reaction times in Bands 1 to 4 is accompanied by a corresponding one or more "Beeps" from the speaker 4.
• the system responds to CALCULATE REACTION TIME THRESHOLDS FROM REACTION TIME AVERAGE AND STANDARD DEVIATIONS and all outputs resulting from testing in the four bands are further tested to ADJUST PARAMETERS FOR DIURNAL VARIATION followed by ADJUST PARAMETERS FOR RUN DURATION and DELAY BY CALCULATED AMOUNT.
• the system also has provision for interaction by the driver, for example if the driver is conscious of onset of a sleep episode, whereby the system recognises that there is an affirmative answer to the question DRIVER FLAGGED SLEEP EPISODE? A further adjustment is provided to INCREASE SENSITIVITY.
• the transducer 9 comprises a flexible sheath 12 which extends circumferentially of the rim 11 in plan but only partially circumferentially of the rim 11 in transverse cross section and thus terminates in walls 13, 14 are which spaced apart by a gap 15 to permit assembly of the transducer 9 on and removal of the transducer 9 from the rim 11 and to accommodate spokes of the steering wheel.
• the walls 13, 14 and an opposite facing surface of the rim 11 have secured thereto complimentary components 16, 17 which are adapted to removably secure one to another whereby the sheath 12 is locatable on the rim 11 in non-slip condition.
• the sheath 12 includes a plurality of cells 18 at least some of which contain components (not shown) of an electrical circuit including switch means (not shown) which is operable when the sheath 12 is squeezed by the hand or hands of a driver of the vehicle while the driver is steering the vehicle.
• the electrical circuit would include a power source contained in one of the cells 18 and switch means would be operable in response to change of air pressure contained in at least some of the cells 18 as a result of the squeezing action by the driver.
• the electrical circuit may include resistive or capacitive components contained in one or more of the cells 18, the electrical properties of which components vary when the sheath 12 is squeezed by the driver.
• the electrical circuit would also include a cableless data transmission system using ultrasonic, IR or RF signals.
• the switch means may be located in a plurality of the cells 18 so that the switch means is operable in any hand held position throughout 360 degree positioning of hands on the steering wheel.
• the transducer comprises a strap 20 to be worn on the wrist of the driver 8.
• the strap. 20 carries a sensor strip 21 on an inner surface thereof, a processing unit 22, a power source 23 and a transmitter 24.
• the sensor strip 21 is adapted to respond to muscle or nerve activity at the wrist of the driver 8 when the driver squeezes a steering wheel when controlling a vehicle as a result of which a signal is generated by the transmitter 24 and is received by the transmitter/receiver 2.
• the transducer 19 may be incorporated into a watch or be a dedicated wrist band.
• the transducer comprises a clip 26 for attachment to a watch strap or bracelet, a sensor strip 27 adapted to respond to muscle or nerve activity at the wrist of the driver 8 when the driver squeezes a steering wheel when controlling a vehicle, a processing unit 28, a power source 29 and a transmitter 30.
• the transducer 25 operates in a similar manner to the transducer 19.
• a monitor in accordance with the present invention may provide visual stimuli instead of audible stimuli.
• the system may include a visual display similar but additional to the display 6 for the purpose of providing public information.
• a visual display would be advantageous for public service vehicles since it would provide an indication to passengers of the vehicles as to the state of alertness of the driver.
• system may include a memory and playback facility such that the driver response profile during a period prior to an accident could be analysed to determine if fatigue was a factor in the accident. It will also be appreciated that the system may include a variable pitch alarm.
• system may include a tachograph connection
• system may be included in the engine management control of a vehicle.
• system may be adapted to be communicated to a control network at a remote location.
• system may be amplified and frequency auto-varied to penetrate ambient noise.
• system may be included in a head-up display.
• system may include digitised voice production.

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• Engineering & Computer Science (AREA)
• Business, Economics & Management (AREA)
• Emergency Management (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Transportation (AREA)
• Mechanical Engineering (AREA)
• Measurement Of The Respiration, Hearing Ability, Form, And Blood Characteristics Of Living Organisms (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=10765174

Family Applications (1)

Country Status (3)

Cited By (2)

Families Citing this family (15)

Family Cites Families (8)

• 1994
  • 1994-11-28 GB GB9424116A patent/GB9424116D0/en active Pending
• 1995
  • 1995-11-28 WO PCT/GB1995/002775 patent/WO1996016830A1/en not_active Application Discontinuation
  • 1995-11-28 EP EP95937131A patent/EP0793582A1/de not_active Withdrawn

Non-Patent Citations (1)

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