Electronic engine control apparatus

• US 5,189,621 A
• Filed: 12/03/1990
• Issued: 02/23/1993
• Est. Priority Date: 05/06/1987
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Funabashi, Motohisa, Shioya, Makoto, Sekozawa, Teruji, Onari, Mikihiko
• Primary Examiner(s): Trans, Vincent N.
• Application Number:
  US07/622,217
• Time in Patent Office: 813 Days
• Field of Search: 364/431.01, 364/431.03, 364/431.04, 364/431.05, 364/424.01, 364/148, 364/150, 364/151, 364/152, 364/154, 123/480, 123/350, 395/905
• US Class Current: 701/102
• CPC Class Codes: B60K 31/0008 including means for detecting potential obstacles in vehicle path
• CPC Class Codes: B60W 10/04 including control of propulsion units
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/11 Stepped gearings
• CPC Class Codes: B60W 2050/0057 Frequency analysis, spectral techniques or transforms
• CPC Class Codes: B60W 2540/106 Rate of change
• CPC Class Codes: B60W 2540/12 Brake pedal position
• CPC Class Codes: B60W 2540/30 Driving style
• CPC Class Codes: B60W 2710/0616 Position of fuel or air injector
• CPC Class Codes: B60W 2710/0622 Air-fuel ratio
• CPC Class Codes: B60W 2710/065 Idle condition
• CPC Class Codes: B60W 30/18 Propelling the vehicle
• CPC Class Codes: B60W 30/1819 Propulsion control with control means using analogue circuits, relays or mechanical links
• CPC Class Codes: B60W 40/09 Driving style or behaviour
• CPC Class Codes: B60W 50/0097 Predicting future conditions
• CPC Class Codes: F02D 11/105 characterised by the function converting demand to actuation, e.g. a map indicating relations between an accelerator pedal position and throttle valve opening or target engine torque
• CPC Class Codes: F02D 2200/606 Driving style, e.g. sporty or economic driving
• CPC Class Codes: F16H 2061/0081 Fuzzy logic
• CPC Class Codes: F16H 59/08 Range selector apparatus
• CPC Class Codes: Y10S 706/90 Fuzzy logic

Abstract

An electronic engine control apparatus includes: a plurality of first sensors for detecting the driving action taken in accordance with a driver'"'"'s intent; a plurality of second sensors for detecting the operating conditions of a vehicle and an engine; a plurality of actuators for controlling the engine; a unit for discriminating the driver'"'"'s intent of how to drive the vehicle based on output signals from the first and second sensors; and a unit for controlling the engine to match the driver'"'"'s intent by selectively adjusting at least one of the actuators, in accordance with the discriminated driver'"'"'s intent.

Claims

1. A method of controlling an internal combustion engine for a vehicle comprising the steps as follows:

detecting a plurality of driving actions made by an operator of the vehicle;

detecting a plurality of operating conditions of the vehicle;

estimating a driver'"'"'s preference for driveability of the vehicle comprising determining occurrence frequencies of the driving actions and operating conditions over a predetermined period; and

,

selectively adjusting engine operation in accordance with the estimated driver'"'"'s preference.

2. The method as described in claim 1 wherein the estimating further includes:

categorizing the driving actions and operating conditions into preselected ranges representative of the driver'"'"'s preference;

processing the occurrence frequencies relative to the ranges with a membership function and a weighing function to identify possibility values for an each one of plural types of driver'"'"'s preference for an each one of the driving actions and operating conditions; and

,

summing the possibility values for the each type of driver'"'"'s preference to identify the estimated driver'"'"'s preference as having a maximum possibility value.

3. An electronic engine control apparatus for selectively adjusting vehicle operation by categorizing the driving action and operating conditions with respect to plural types of a driving environment of a vehicle and/or a driver'"'"'s preference for driveability and by discriminating at least one of the plural types, comprising:

a plurality of first sensors for detecting the driving action taken by a driver and including means for generating a first output signal value representative thereof;

a plurality of second sensors for detecting the operating conditions of the vehicle and an engine and including means for generating a second output signal value representative thereof;

discrimination means for classifying the first and second output signal values into a plurality of predetermined ranges, for calculating occurrence frequencies in respective ranges of the output signal values, for calculating a possibility value of the plural types by combining the calculated occurrence frequencies in the respective ranges of the output signal values of said first and second sensors and for determining the one of the plural types which has a largest possibility value among the plural types as a driving environment and/or a driver'"'"'s preference at a present time; and

,

control means for controlling the engine by selectively adjusting at least one of a plurality of actuators for controlling the engine in accordance with the determined type.

4. An electronic engine control apparatus according to claim 3, wherein said discrimination means includes means for measuring the first and second output signals from said first and second sensors a plurality of times during a plurality of engine cycles, and means for discriminating the driving environment and/or driver'"'"'s preference, in accordance with said measured values.

5. An electronic engine control apparatus according to claim 4, further including means for classifying the driving environments of a vehicle into a congested road, an urban street, a suburban road, a mountain road, and a highway, and said discrimination means includes means for discriminating the driving environment in accordance with output signals from said first and second sensors.

6. An electronic engine control apparatus according to claim 5, wherein said second sensors include a vehicle speed sensor for detecting a vehicle speed, a revolution number sensor for detecting a number of revolutions of an engine, and a throttle valve position sensor for detecting an opening degree of a throttle valve, and wherein,

said discrimination means includes means for discriminating the driving environment of the vehicle in accordance with output signals from said vehicle speed sensor, revolution number sensor and throttle valve position sensor.

7. An electronic engine control apparatus according to claim 6, wherein said discrimination means includes means for calculating an engine revolution number change ratio using an output signal from said revolution number sensor, further for calculating a throttle valve opening degree change ratio using an output signal from said throttle valve position sensor, and for classifying the obtained vehicle speed, revolution number change ratio and throttle valve opening degree change ratio into large, middle and small ranges, and wherein

said discrimination means includes means for discriminating the driving environment as a highway if the vehicle speed is high, as a congested road if the vehicle speed is low and the engine acceleration is small, as a mountain road if the throttle valve opening degree change ratio and the revolution number change ratio are large, and as an urban street if the vehicle speed and the engine revolution number change ratio take intermediate values.

8. An electronic engine control apparatus according to claim 5, wherein said discrimination means comprises:

a unit for calculating the occurrence frequencies in the respective ranges of each output signal value by applying membership functions of a Fuzzy theory to the output signals of said first and second sensors;

a unit for obtaining the possibility value of each driving environment by performing a conversion matrix calculation from the occurrence frequencies in the respective ranges of each output signal into the driving environments; and

a unit for discriminating an objective driving environment which has a maximum possibility value among the driving environments.

9. An electronic engine control apparatus according to claim 5, wherein said first sensors include a gear shift sensor for detecting a gear shift by a shift lever, a brake sensor for detecting a depression of a brake pedal, an accelerator pedal sensor for detecting a depression of an accelerator pedal, and a steering sensor for detecting a motion of a steering, and said second sensors include a vehicle speed sensor for detecting a vehicle speed and wherein

said discrimination means includes means for classifying the frequency of the gear shift, the frequency of the steering, the frequency of the brake depression and the frequency of the accelerator pedal depression into the respective ranges, respectively, in accordance with the output signals from said first and second sensors, for classifying the vehicle speed into the respective ranges for discriminating the driving environments based on the classification results.

10. An electronic engine control apparatus according to claim 9 wherein said discrimination means includes means for discriminating the driving environment as a highway running if the vehicle speed is high and the frequency of the gear shift is large, and as a congested road running if the vehicle speed is low and the frequency of the brake pedal depression is high.

11. An electronic engine control apparatus according to claim 10 wherein said discrimination means includes means for discriminating the driving environment as a mountain road running if both the frequencies of the steering motion and the depression change between the brake and accelerator pedals are large.

12. An electronic engine control apparatus according to claim 9 wherein said discrimination means includes means for discriminating the driving environment as an urban street running if both the frequencies of the steering motion and the brake actuation are high.

13. An electronic engine control apparatus according to claim 9 wherein said discrimination means includes means for discriminating the driving environment as a suburban road running if the vehicle speed is maintained near a limited speed and the frequency and range of the steering motion are small.

14. An electronic engine control apparatus according to claim 5, wherein one of said plurality of actuators is fuel injection valves, and wherein

said control means includes means for controlling said fuel injection valves in such a manner that the ratio of an injected fuel amount to a sucked air amount increases relatively at said respective driving environments of the congested road, urban street, mountain road and highway in this order.

15. An electronic engine control apparatus according to claim 5, wherein one of said plurality of actuators is ignition plugs, and wherein

said control means includes means for controlling said ignition plugs in such a manner that ignition timings advance relatively at said respective driving environments of the congested road, urban street, mountain road, and highway in this order.

16. An electronic engine control apparatus according to claim 5, wherein one of said plurality of actuators is a means for adjusting a repulsion force of an accelerator pedal, and wherein,

said control means includes means for controlling said repulsion force adjusting means in such a manner that the repulsion force is reduced relatively at said respective driving environments of the congested road, urban street, mountain road, and highway in this order.

17. An electronic engine control apparatus according to claim 5, wherein one of said plurality of actuators is means for controlling a throttle valve opening degree through conversion of the depression angle of an accelerator pedal into the throttle valve opening degree, and wherein

said control means includes means for controlling said throttle valve opening degree controlling means in a manner that conversion ratios from the accelerator pedal depression angle into the throttle valve opening degree increase relatively at said respective driving environments of the congested road, urban street, mountain road, and highway in this order.

18. An electronic engine control apparatus according to claim 4, further including means for classifying the driver'"'"'s preference to driveability into sporty, normal, and gentle types, and said discrimination means includes means for discriminating the driver'"'"'s preference in accordance with the output signals from said first and second sensors.

19. An electronic engine control apparatus according to claim 18, wherein said discrimination means comprises:

a unit for calculating the occurrence frequencies of respective ranges of each output signal value by applying membership functions of a Fuzzy theory to the output signals of said first and second sensors;

a unit for obtaining the possibility value of each driver'"'"'s preference by performing conversion matrix calculation from the occurrence frequencies in the respective ranges of each output signal into the driver'"'"'s preferences; and

a unit for discriminating an objective driver'"'"'s preference which has a maximum possibility value among the driver'"'"'s preferences.

20. An electronic engine control apparatus according to claim 18, wherein said first sensors include a sensor for detecting the depression angle of an accelerator pedal, and wherein

said discrimination means includes means for discriminating the preferences as a sporty type if the driver abruptly depresses the accelerator pedal.

21. An electronic engine control apparatus according to claim 18, wherein said first sensors include a sensor for detecting the depression position of an accelerator pedal, and a sensor for detecting the depression position of a brake pedal, and wherein

said discrimination means includes means for discriminating the driver'"'"'s preference to driveability based on the depressions and depression frequencies of the accelerator and brake pedals.

22. An electronic engine control apparatus according to claim 18, wherein said first sensors include a sensor for detecting the depression position of an accelerator pedal, a sensor for detecting a depression position of a brake pedal, and a sensor for detecting a gear position of a shift lever,

said second sensors include a sensor for detecting a vehicle speed, and a sensor for detecting an engine revolution number, and

said discrimination means includes means for discriminating the driver'"'"'s preference based on the output signals from said first and second sensors.

23. An electronic engine control apparatus according to claim 18 wherein one of said plurality of actuators is fuel injection valves, and wherein

said control means includes means for controlling said fuel injection valves in such a manner that the ratios of an injected fuel amount to a sucked air amount increase relatively as said respective driver'"'"'s preference to the gentle, normal, and sporty types in this order.

24. An electronic engine control apparatus according to claim 18, wherein one of said plurality of actuators is ignition plugs, and wherein

said control means includes means for controlling said ignition plugs in such a manner that the ignition timings advance relatively at said respective driver'"'"'s preference to the gentle, normal, and sporty types in this order.

25. An electronic engine control apparatus according to claim 24, wherein one of said plurality of actuators is means for adjusting the repulsion force of an accelerator pedal, and wherein

said control means includes means for controlling said repulsion force adjusting means in such a manner that the repulsion forces reduce relatively at said respective driver'"'"'s preferences to the gentle, normal, and sporty types in this order.

26. An electronic engine control apparatus according to claim 18, wherein one of said plurality of actuators is means for controlling a throttle valve opening degree through conversion of the depression angle of an accelerator pedal into the throttle valve opening degree, and wherein

said control means includes means for controlling said throttle valve opening degree controlling means in such a manner that conversion ratios from the accelerator pedal depression angle into the throttle valve opening degree increase relatively at said respective driver'"'"'s preferences to the gentle, normal, and sporty types in this order.

27. An electronic engine control apparatus according to claim 18, wherein said discrimination means includes means for detecting a transition condition of the driving condition based on the output signals from said first and second sensors, and for discriminating the driver'"'"'s preference based on the output signals from said first and second sensors during the transition condition.

28. An electronic engine control apparatus according to claim 27 wherein said discrimination means includes means for detecting a driving start as said transition condition, for calculating an accelerator pedal depression position change ratio based on an output signal of an accelerator pedal depression position sensor as said first sensor, and for discriminating the driver'"'"'s preference based on the depression position change ratio at the driving start.

29. An electronic engine control apparatus according to claim 28, wherein said discrimination means includes means for classifying the accelerator pedal depression change ratios into large, middle, and small types and for discriminating the driver'"'"'s preferences as the sporty, normal, and gentle types if the change ratios are large, middle, and small types, respectively.

30. An electronic engine control apparatus according to claim 18 wherein said second sensors include a revolution number sensor for detecting the number of revolutions of an engine, and a throttle valve position sensor for detecting the opening degree of a throttle valve, and wherein

said discrimination means includes means for discriminating the driver'"'"'s preference in accordance with output signals from said revolution number sensor and throttle valve position sensor.

31. An electronic engine control apparatus according to claim 30, wherein said discrimination means includes means for calculating an engine revolution number change ratio using an output signal from said revolution number sensor, further for calculating a throttle valve opening degree change ratio using an output signal from said throttle valve position sensor, and for classifying the obtained revolution number change ratio and throttle valve opening degree change ratio into the respective ranges, and wherein

said discrimination means includes means for discriminating as the sporty type if the revolution number change ratio, throttle valve opening degree, and throttle valve opening degree change ratio are large, as the normal type if they are middle, and as the gentle type if they are small.

32. An electronic engine control apparatus according to claim 4, further including means for classifying the driving environments of the vehicle and the driver'"'"'s preferences to driveability into a plurality of types, and for discriminating a particular type in accordance with the output signals from said first and second sensors.

33. An electronic engine control apparatus according to claim 32, including means for classifying the driving environments into a highway, congested road and other driving environments, and further for classifying the driver'"'"'s preference to sporty, normal, and gentle types.

34. An electronic engine control apparatus according to claim 33, wherein said second sensors include a vehicle speed sensor for detecting a vehicle speed, a revolution number sensor for detecting the number of revolutions of an engine, and a throttle valve position sensor for detecting the opening degree of a throttle valve, and wherein

said discrimination means includes means for discriminating the present time driving environment in accordance with output signals from said vehicle speed sensor, revolution number sensor, and throttle valve position sensor.

35. An electronic engine control apparatus according to claim 34, wherein said discrimination means includes means for calculating an engine revolution number change ratio using an output signal from said revolution number sensor, further for calculating a throttle valve opening degree change ratio using an output signal from said throttle valve position sensor, and for classifying the obtained vehicle speed, revolution number change ratio, and throttle valve opening degree change ratio into respective ranges, and wherein

said discrimination means includes means for discriminating the driving environment as the highway if the vehicle speed is high, as the congested road if the vehicle speed is low and the engine revolution number change ratio is small, and

discriminating the driver'"'"'s preference as the sporty type is the engine revolution number change ratio, throttle valve opening degree and throttle valve opening degree change ratio are large, as the normal type if they are middle, and as the gentle type if they are small.

36. An electronic engine control apparatus according to claim 33, wherein one of said plurality of actuators is fuel injection valves, and wherein

said control means includes means for setting a first air/fuel mixture ratio if the driving environment is a congested road or the driver'"'"'s preference is the gentle type, a second air/fuel mixture ratio if the driver'"'"'s preference is the normal type, and a third air/fuel mixture ratio if the driving environment is the highway or the driver'"'"'s preference is the sporty type, and for controlling the fuel injection valve in a manner that the mixture ratios increase relatively at the respective mixture ratios of the first, second, and third ratios in this order.

37. An electronic engine control apparatus according to claim 33, wherein one of said plurality of actuators is ignition plugs, and wherein

said control means includes means for setting first spark timings if the driving environment is the congested road or the driver'"'"'s preference is the gentle type, second spark timings if the driver'"'"'s preference is the normal type, and third spark timings if the driving environment is the highway or the driver'"'"'s preference if the sporty type, and for controlling the ignition plugs in such a manner that the spark timings advance relatively at the respective spark timings of the first, second, and third spark timings in this order.

38. An electronic engine control apparatus according to claim 33, wherein one of said plurality of actuators is means for adjusting a repulsion force of an accelerator pedal, and wherein

said control means includes means for setting a first repulsion force if the driving environment is the congested road or the driver'"'"'s preference is the gentle type, a second repulsion force if the driver'"'"'s preference is the normal type, and a third repulsion force if the driving environment is the highway or the driver'"'"'s preference is the sporty type, and for controlling said repulsion force adjusting means in such a manner that the accelerator pedal repulsion forces reduce relatively at said respective repulsion force of the first, second, and third repulsion forces in this order.

39. An electronic engine control apparatus according to claim 33, wherein one of said plurality of actuators is means for controlling a throttle valve opening degree through conversion of the depression angle of an accelerator pedal into the throttle valve opening degree, wherein

said control means includes means for setting a first conversion ratio of the accelerator pedal depression angle into the throttle valve opening degree if the driving environment is the congested road or the driver'"'"'s preference is the gentle type, a second conversion ratio if the driver'"'"'s preference is the normal type, and a third conversion ratio if the driving environment is the highway or the driver'"'"'s preference is the sporty type, and for controlling said throttle valve opening degree controlling means in such a manner that the conversion ratios increase relatively at the respective conversion ratios of the first, second, and third conversion ratios in this order.

41. An electronic engine control apparatus according to claim 4, including means for classifying the driving action of a driver in acceleration periods into a plurality of acceleration characteristic patterns, and said discrimination means include means for discriminating a present time acceleration characteristic pattern based on the output signals from said first and second sensors, and wherein

said control means includes an acceleration rate controlling mechanism for changing the coefficient of said acceleration rate controlling mechanism in accordance with the discriminated acceleration characteristic pattern.

40. An electronic engine control apparatus according 32, wherein said discrimination means comprises:

a unit for calculating the occurrence frequencies of the respective ranges of each output signal value by applying membership functions of a Fuzzy theory to the output signals of said first and second sensors;

a unit for obtaining the possibility value of each driving environment and each driver'"'"'s preference by performing conversion matrix calculation from the occurrence frequencies of the respective ranges of each output signal into the driving environments and the driver'"'"'s preferences; and

a unit for discriminating an objective driving environment and an objective driver'"'"'s preference which have maximum possibility values among the driving environments and the driver'"'"'s preferences, respectively.

42. An electronic engine control apparatus useful for implementing a plurality of types of operation for a vehicle comprising:

a plurality of first sensors for detecting a driving action taken by a driver;

a plurality of second sensors for detecting operating conditions of the vehicle and an engine;

discriminating means

for classifying output signal values of each of said first and second sensors measured during a predetermined period into a plurality of predetermined ranges comprised of possible output signal values,

for calculating occurrence frequencies in respective ones of the ranges of the output signal values of each of said first and second sensors,

for converting the calculated occurrence frequencies into driving condition signals, and

for discriminating one of the types in accordance with the driving condition signals; and

,

control means for controlling the engine by selectively adjusting at least one of a plurality of actuators for controlling the engine in accordance with the discriminated type.

43. An electronic engine control apparatus useful for implementing a plurality of types of operation for a vehicle comprising:

a plurality of first sensors for detecting a driving action taken by a driver;

a plurality of second sensors for detecting operating conditions of the vehicle and an engine;

discriminating means

for classifying output signal values of each of said first and second sensors into a plurality of predetermined ranges by supplying the measured values to a membership function utilized in Fuzzy theory,

for calculating occurrence frequencies in respective ones of the ranges of the output signal value of each of said first and second sensors,

for converting the calculated occurrence frequencies into driving condition signals, and

for discriminating one of the types in accordance with the driving condition signals; and

,

control means for controlling the engine by selectively adjusting at least one of a plurality of actuators for controlling the engine in accordance with the discriminated type.

44. An electronic engine control apparatus useful for implementing a plurality of types of operation for a vehicle comprising:

a plurality of first sensors for detecting a driving action taken by a driver;

a plurality of second sensors for detecting operating conditions of the vehicle and an engine;

discriminating means

for classifying output signal values of each of said first and second sensors measured during a predetermined period into a plurality of ranges by supplying the measured values to a membership function utilized in Fuzzy theory,

for calculating occurrence frequencies in respective ranges of the output signal value of each of said first and second sensors,

for converting the calculated occurrence frequencies into driving condition signals, and

for discriminating one of the types in accordance with the driving condition signals; and

,

control means for controlling the engine by selectively adjusting at least one of a plurality of actuators for controlling the engine in accordance with the discriminated type.

45. An electronic engine control apparatus useful for implementing a plurality of types of operation for a vehicle comprising:

a plurality of first sensors including a gear shift sensor, a brake pedal sensor, an accelerator pedal sensor, and a steering sensor for detecting a driving action taken by a driver;

a plurality of second sensors for detecting operating conditions of the vehicle and an engine;

discriminating means

for classifying output signal values of each of said first and second sensors including the gear shift sensor, the brake pedal sensor, the accelerator pedal sensor, and the steering sensor, into a plurality of ranges by supplying the measured values to a membership function utilized in Fuzzy theory,

for calculating occurrence frequencies in respective ranges of the output signal value of each of said first and second sensors,

for converting the calculated occurrence frequencies into driving condition signals, and

for discriminating one of the types in accordance with the driving condition signals; and

,

control means for controlling the engine by selectively adjusting at least one of a plurality of actuators for controlling the engine in accordance with the discriminated type.

46. An electronic engine control apparatus useful for implementing a plurality of types of operation for a vehicle comprising:

a plurality of first sensors for detecting a driving action taken by a driver;

a plurality of second sensors for detecting operating conditions of the vehicle and an engine;

discriminating means

for classifying output signal values of each of said first and second sensors measured during a predetermined period into a plurality of ranges,

for calculating occurrence frequencies in respective ranges of the output signal value of each of said first and second sensors,

for converting the calculated occurrence frequencies into driving condition signals, and

for discriminating one of the types representing an intent of the driver, in accordance with the driving condition signals; and

,

control means for controlling the engine by selectively adjusting at least one of a plurality of actuators of controlling the engine in accordance with the discriminated type.

47. A method of controlling an internal combustion engine for a vehicle comprising the following steps:

detecting a plurality of driving actions made by an operator of the vehicle;

detecting a plurality of operating conditions of the vehicle;

estimating a driving condition of the vehicle comprising determining occurrence frequencies of the driving actions and operating conditions over a predetermined period; and

,

selectively adjusting engine operation in accordance with the estimated driving condition.

48. The method as described in claim 47 wherein said estimating further includes categorizing the driving actions and operating conditions into preselected ranges representative of a feature of the driving conditions.

49. The method as described in claim 48 wherein the pluralities of driving actions and operating conditions are processed with a membership function to determine data representative of the occurrence frequencies.

50. The method as described in claim 49 wherein the data representative of the occurrence frequencies is selectively weighted relative to a one driving condition to estimate an each driving condition representative of an each of the detected pluralities of the driving actions and the operating conditions.

51. The method as described in claim 50 wherein the estimating further includes summing the each driving condition estimated to determine the driving condition of the vehicle.

52. The method as described in claim 47 wherein the detecting comprises detecting driving actions and operating conditions for estimating the driving condition representative of a driving preference.

53. The method as described in claim 47 wherein the detecting comprises detecting driving actions and operating conditions estimating the driving conditions representative of a driving environment.

54. The method as described in claim 47 wherein the detecting comprises detecting driving actions and operating conditions for estimating the driving conditions representative of a driver'"'"'s preference and driving environment.

55. The method as described in claim 47 wherein the detecting comprises detecting driving actions and operating conditions during transition conditions.

56. The method as described in claim 47 wherein the detecting comprises classifying driving actions including accelerator pedal actions into preselected driving action classes.

57. The method as described in claim 56 further including comparing a target acceleration rate of the vehicle with an actual vehicle acceleration rate and selectively adjusting a vehicle throttle valve to adjust the actual vehicle acceleration rate to the target acceleration rate in accordance with results of the comparing.

58. A condition adaptive-type control method for an internal combustion engine mounted on an automotive vehicle having a transmission mechanism, a brake pedal and an accelerator pedal, comprising the steps of:

categorizing a driver'"'"'s preference and a vehicle driving environment, respectively, into a plurality of categories, and preparing different engine control methods for different combinations of said categories;

detecting a plurality of measurable variables including

driving actions made by an operator of the vehicle comprising a state of engagement or disengagement of said transmission mechanism, an angle of said brake pedal and an angle of said accelerator pedal, and

vehicle operating conditions comprising a speed of the vehicle;

determining possibility values for the categories to estimate a one present time driver'"'"'s preference and a one present time driving environment, each having maximum possibility values, respectively, comprising processing occurrence frequencies of the measurable variables in a Fuzzy theory analysis relative to the categories to determine the possibility values, and associating the possibility values to identify the maximum possibility values; and

,

selecting one of said engine control methods in accordance with a combination of said categories corresponding to the one present time driver'"'"'s preference and the one present time driving environment.

59. A method of controlling an internal combustion engine for an automotive vehicle comprising the following steps:

detecting a plurality of driving actions made by an operator of the vehicle;

detecting a plurality of operating conditions of the vehicle;

categorizing the driving actions and operating conditions with respect to plural types of the driving environment of the vehicle and/or a driver'"'"'s preference for driveability;

estimating a present time one of the plural types by determining occurrence frequencies of the driving actions and the operating conditions over a predetermined period relative to preselected ranges representative of the plural types and by calculating a maximum possibility value of the present time one using the occurrence frequencies; and

,

selectively adjusting engine operation in accordance with the estimated present time one of the plural types.