JP2800505B2 - Automated driving system for vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for automatically driving a vehicle on a chassis dynamometer, and more particularly to a control of an accelerator actuator.

[0002]

2. Description of the Related Art A small, lightweight, and easily attachable / detachable automatic driving device using an air cylinder has been developed for an exhaust / fuel efficiency evaluation experiment in which a test vehicle is frequently changed. The meeting's preprint 862).

To explain this, as shown in FIG. 14, this device is a double-acting type that drives an accelerator pedal 42, a brake pedal 43, a clutch pedal 44 and a shift lever 45 of a test vehicle 41 in accordance with a command stroke. An actuator composed of each air cylinder 46, an electromagnetic valve unit 48, an electromagnetic valve drive circuit 49 provided as many as the number of the air cylinders 46, an actuator control unit composed of an 8-bit one-chip microcomputer 50, and a general-purpose 16-bit personal computer And a main control unit 55.

The engine speed Ne, the vehicle speed, and the current position of the air cylinder 46 (detected by the potentiometer 47)
And a personal computer 5 to which external commands are input
In FIG. 5, “teaching (automatic measurement)”, “automatic traveling”, “manual traveling”,
Each operation of “end” can be selected, and the selected operation is executed by the CPU in the computer.

[0005] Of these, "teaching" includes two teachings: a gear change position of the transmission and each pedal position. In the former, a tester manually operates the shift lever 45 of the transmission to perform a gear change. By doing so, each gear position is stored in the memory in the computer as teaching data. In the latter case, the device automatically depresses each of the pedals 42 to 44 based on a program, thereby storing the play allowance of the accelerator pedal 42, the position where the brake pedal 43 starts to work, the engaged position of the clutch, and the like.

When "automatic traveling" is selected, the actual vehicle speed from the chassis dynamometer is compared with the command vehicle speed required from the memory, and the accelerator pedal 42 and the brake pedal 43 are adjusted so that the actual vehicle speed matches the command vehicle speed. Is determined, and the timing and position for instructing each air cylinder 46 are determined. Air cylinder 46
Is output to the microcomputer 50 together with its current position Li.

A microcomputer 50 for controlling the current position Li of the air cylinder 46 to coincide with the commanded position Ls finds a difference ΔL between the commanded position Ls and the current position Li, and stores a valve opening time according to this ΔL in a table. Determine with reference to the data. An electromagnetic valve (FIG. 1) for driving the air cylinder 46 in accordance with the positive or negative sign given to ΔL.
In step 6, A, A 'or B, B') is selected and opened.

For example, in FIG. 16, in order to further depress the accelerator pedal 42, the piston 4 of the air cylinder 46 is
To move 6A from the current position Li to the command position Ls,
Select the side of the solenoid valves A and A 'and set these solenoid valves A and A' to Δ
Open for a valve opening time corresponding to L. The sides of the solenoid valves B and B 'are closed.

The solenoid valves A, A ', B, B' are not actually one by one, but are opened to the inlet 58A through which an air pressure of 5 kgf / cm ² is introduced and to the atmospheric pressure as shown in FIG. Two solenoid valves are connected in parallel to an air gallery 58 provided with an outlet 58B. This is the air cylinder 4
This is because if the load acting on the piston 46A and the air flow rate are the same, the piston speed increases as the number of solenoid valves increases. In the air cylinder for the clutch pedal, three electromagnetic valves are used as a pair in order to shorten the shift time.

By opening the solenoid valves A and A ', 5 kgf /
When the air pressure of cm ² is applied to the right chamber 46B of the air cylinder 46 via the solenoid valve A and the air in the left chamber 46C is released to the atmosphere via the solenoid valve A ', the piston 46A is moved to the command position L.
Move to s. The movement of the piston 46A causes the accelerator pedal 42 to move through the wire 56 and the link mechanism 57.
Is stepped on.

By controlling the position of the air cylinder 46, the pedals 42 to 44 and the shift lever 45 operate to perform automatic traveling.

[0012]

However, in such a device, the actual vehicle speed is compared with the command vehicle speed, and the position of the air cylinder 46 is controlled so that the actual vehicle speed matches the command vehicle speed. It is necessary to set an optimal control gain (constant when converting the deviation between the commanded vehicle speed and the actual vehicle speed into an operation amount of the air cylinder (hereinafter referred to as “stroke”)) for the test vehicle.

In this case, when the vehicle changes, the value of the optimum control gain also changes, so that the control gain must be changed for each test vehicle. This is the same when the load condition of the chassis dynamometer is changed. That is, since the optimum control gain varies depending on the vehicle and the command vehicle speed data stored in the memory, the adjustment is complicated and takes a long time.

Therefore, prior to automatic traveling, the relationship between the stroke commanded to the air cylinder for the accelerator pedal (accelerator actuator) by teaching and the engine output torque and the relationship between the engine friction horsepower and the engine speed are tabulated in a table. When traveling, at the time of acceleration or steady, by determining the stroke commanded to the accelerator actuator using the stroke-torque table,
The adjustment time required for setting the vehicle can be shortened, and at the time of deceleration, by using the above-mentioned friction horsepower-revolution number table to determine whether or not deceleration can be performed by engine braking, unnecessary braking is prevented. can do.

However, in a vehicle equipped with an automatic transmission, when the accelerator pedal is greatly depressed in a low-to-medium rotation range to cause a kick-down, the engine output torque and the accelerator actuator stroke become higher on the load side than the kick-down point. Relationship cannot be determined.
If the relationship between the two cannot be expressed in a table, vehicle speed control becomes impossible.

Accordingly, the present invention shortens the adjustment time required for setting the vehicle, prevents unnecessary braking, and obtains a torque-stroke relationship for a low-to-medium rotation range where kickdown works, instead of actually measuring it. Accordingly, an object of the present invention is to cause a vehicle equipped with an automatic transmission that works to kick down to perform automatic driving.

[0017]

According to a first aspect of the present invention, as shown in FIG. 1, in a vehicle including an automatic transmission in which a kick-down mechanism works in a low to middle rotation range, an accelerator pedal 1 is driven according to a command stroke. Accelerator actuator 2
A sensor 3 for detecting a vehicle speed, a means 4 for calculating the speed of change of the vehicle speed, a sensor 5 for detecting the engine speed Ne, and the vehicle speed, the speed of change and the engine speed Ne at that time by teaching. Means for storing the relationship between the output torque of the engine for the high speed range and the stroke of the axle actuator for generating this torque in the form of a numerical table, and the relationship between the rotation speed and the accelerator actuator stroke at no load by teaching. Means 15 for storing in a table, the relationship between the no-load speed and the stroke, and the engine speed previously determined
Means 16 for moving and correcting the torque-stroke relationship for the high rotation range using the output characteristic correction coefficient calculated from the torque relationship to determine the torque-stroke relationship for the low-medium rotation range; Means 17 for storing in table form, and means 8 for storing data of the commanded vehicle speed in advance
Means 9 for calculating the speed of change of the commanded vehicle speed, means 10 for calculating the horsepower required for the vehicle to travel at these commanded vehicle speeds and the speed of change, and whether the vehicle must be accelerated from the required horsepower PS or A means 11 for determining whether or not a steady state is required, and a means 12 for converting the required horsepower PS into an engine output torque T at the engine rotation speed Ne at that time when the vehicle must be accelerated or the steady state is required based on the determination result. Means 13 for calculating an accelerator actuator stroke for generating the converted torque T by selecting and using one of the plurality of stroke-torque tables according to the rotation range at that time; and And means 14 for instructing the control unit 2.

According to a second aspect of the present invention, as shown in FIG. 2, in a vehicle equipped with an automatic transmission in which a kick-down mechanism works in a low to middle rotation range, an accelerator actuator 2 for driving an accelerator pedal 1 in accordance with a command stroke is provided. A brake actuator 22 for driving a brake pedal 21 according to a command stroke, a sensor 3 for detecting a vehicle speed, a means 4 for calculating a change speed of the vehicle speed, a sensor 5 for detecting an engine speed Ne, a teaching The vehicle speed, its changing speed and the engine speed Ne at that time.
Means for storing the relationship between the output torque of the engine for the high speed range and the stroke of the axle actuator for generating this torque in the form of a numerical table, and the relationship between the rotation speed and the accelerator actuator stroke at no load by teaching. Means 15 for storing in a table, the relationship between the no-load rotation speed and the stroke, and the relationship between
Output characteristics calculated from the relationship between engine speed and torque
Means 16 for moving and correcting the torque-stroke relationship for the high rotation range using the correction coefficient to determine the torque-stroke relationship for the low-medium rotation range, and means 17 for storing this relationship in a numerical table, By the teaching, the vehicle speed, the change speed thereof and the engine speed N at that time are obtained.
means 24 for storing the relationship between the friction horsepower F of the engine and the engine speed Ne in the form of a numerical table using the relationship of e, and the friction horsepower F with respect to the engine speed Ne at that time is expressed by the horsepower-rotational number table. Means 25 for calculating using the command vehicle speed, means 8 for storing data of the commanded vehicle speed in advance, means 9 for calculating the change speed of the commanded vehicle speed, and the horsepower PS required for the vehicle to travel at the commanded vehicle speed and the change speed. , A means 26 for determining whether or not to decelerate from the required horsepower PS, and a sum PS + of the required horsepower PS and the friction horsepower F when deceleration is required.
A means 27 for calculating F, a means 28 for judging from the sum PS + F whether the vehicle can be decelerated only by the engine brake or cannot be decelerated by the engine brake alone. Means 29 for calculating a predetermined stroke for the accelerator actuator 2 by selecting one of the plurality of stroke-torque tables when the vehicle can be decelerated.
A means 14 for commanding the stroke to the accelerator actuator 2, a means 30 for calculating a predetermined stroke for the brake actuator 22 when the engine brake cannot decelerate, and a means 31 for commanding the stroke to the brake actuator 22 And According to a third aspect, in the first or second aspect,
And the torque-stroke relationship for the low-medium rotation range.
Is determined by the relationship between the no-load rotation speed and the stroke
Engine that is determined in advance based on the output characteristics in the rotation range
Output in the low and middle rotation range calculated from the relationship between rotation speed and torque
Using the characteristic correction coefficient, the torque
Move and correct the troke relationship to reduce the
Calculate the relationship between lux and stroke. In the fourth invention,
In the first or second invention, the low-medium rotation range
The means for determining the torque-stroke relationship is the no-load rotation.
The relationship between the number and the stroke, and the
Torque value at almost full load and torque at near full load in low to middle rotation range
Using the output characteristic correction coefficient calculated from the
Move and correct the torque-stroke relationship for the shift range.
To calculate the torque-stroke relationship for the low and medium speed range
I do. In a fifth aspect, any one of the first to fourth aspects of the invention
In the above, torque is substantially the maximum as the number of revolutions in the high revolution range.
Set a large rotation speed.

[0019]

According to the first aspect of the present invention, prior to automatically running the test vehicle on the chassis dynamometer, the vehicle speed, its change speed, and the engine speed at that time are used for high test rotation for each test vehicle by teaching. The relationship between the engine output torque for the region and the accelerator actuator stroke that generates the torque is stored in a table.

Further, from the relationship between the torque and the stroke with respect to the high rotation speed range, the relationship between the no-load rotation speed and the stroke and the previously obtained engine speed and torque are obtained.
By performing the movement and correction using the output characteristic correction coefficient calculated from the relationship, the relationship between the torque and the stroke with respect to the low and middle rotation range is stored in a numerical table.

When the vehicle enters automatic running according to commanded vehicle speed data such as a running mode, a horsepower PS required for the vehicle to travel at the commanded vehicle speed specified by the data and its change speed is obtained. It is determined whether the vehicle must be accelerated or stationary.

When the vehicle must be accelerated or steady, the required horsepower is converted into an engine output torque T based on the engine speed at that time, and the accelerator actuator stroke that generates this torque T falls within the rotation range at that time. The calculation is performed by selecting and using one of the plurality of stroke-torque numerical tables.

When this stroke is commanded to the accelerator actuator 2 and the accelerator pedal 1 is further depressed in accordance with the commanded stroke, a torque is generated according to the request, such as whether the accelerator must be accelerated or steady. .

Further, the relationship between the torque and the stroke with respect to the high rotation range is moved and corrected so that the torque with respect to the low and middle rotation range is obtained.
If the stroke relationship is represented by a table, it is not necessary to actually measure the torque-stroke relationship for the low to middle rotation range due to the kick down function, so even a vehicle equipped with an automatic transmission that performs the kick down. As in the case of a vehicle equipped with a manual transmission, the mode traveling during acceleration can be automatically performed.

In the second invention, when it is necessary to decelerate, it is distinguished whether the engine can be decelerated only by the engine brake or if it is insufficient, the brake must be applied by the brake pedal 21. Only when the accelerator pedal 1 is returned and the engine brake cannot be used to decelerate, the brake pedal 21
Braking is performed.

Further, the relationship between the torque and the stroke with respect to the high rotation range is stored in a numerical table, and the relationship between the torque and the stroke with respect to the low and middle rotation range is converted into a numerical table by moving and correcting this relationship. The kick-down function eliminates the need to actually measure the torque-stroke relationship for the low-to-medium rotation range, and even a vehicle equipped with an automatic transmission that works kick-down is decelerated in the same manner as a vehicle equipped with a manual transmission. Mode running at the time can be automatically performed.

[0027]

The mechanical structure of the embodiment is almost the same as that of FIG. 14. The personal computer 55 has an engine speed Ne (obtained from the input of the ignition signal pulse or the voltage conversion input of the pulse) and the feedback signal. The actual vehicle speed (obtained from the voltage input of the tacho generator or the pulse input by the pulse generator) is input to the memory of the personal computer 55, and the command vehicle speed data (for example, the elapsed time required for 10-mode driving and the command A table representing the relationship between vehicle speeds is stored in advance.

The personal computer 55 executes the following operations (1) to (3) unlike the conventional one. In this case, the items (1) and (2) are executed prior to the automatic driving,
(3) is an item to be executed in automatic driving. Hereinafter, description will be made in this order.

(1) Creation of a table by teaching power performance An accelerator actuator (air for an accelerator pedal) is obtained from a steady running or steady state at a predetermined vehicle speed or engine speed (for example, three types of low speed, medium speed and high speed). Different strokes are sequentially given to the cylinders), the speed of change of the vehicle speed is measured for each stroke, and the engine output torque T is calculated from the speed of change and the vehicle speed.

[0030] For example, in response to a command from the personal computer 55, as shown in Figure 3, increasing by a predetermined amount to the point A than the point B the stroke, speed is raised by ΔV in Δt seconds later with a slight delay from V ₁ I do.

The engine output horsepower PS at this time is calculated by the following equation. PS = K ₁ μr WV + K ₂ μc {ρ / (2 g × 3.6 ² )} AV ³ + K ₃ {(W + We) / g} Vα

However, the meanings of the symbols in the formulas are as follows, and values other than the vehicle speed and its change speed α (= ΔV / Δt) are input to the memory of the personal computer 55 for each vehicle. PS; required horsepower _{[Ps] K 1, K 2} , K 3; constant .mu.r; tire rolling resistance coefficient W; vehicle weight [kgf] V; vehicle speed [km / h] μc; front projection of the vehicle; drag coefficient A Area [m ² ] ρ; air density [kg / m ³ ] g; acceleration of gravity [m / s ² ] We; inertia equivalent weight of rotating part [kgf] α; acceleration [m / s ² ]

The PS in the equation is the horsepower required for the vehicle to run at the vehicle speed V and the acceleration α, the first term on the right side is the rolling resistance horsepower, the second term is the windage resistance horsepower, and the third term is the acceleration resistance. It is called horsepower.

On the other hand, when the vehicle travels on the chassis dynamometer, the sum of the rolling resistance horsepower and the windage resistance horsepower is called the steady running horsepower, and is equal to the power absorption horsepower of the chassis dynamometer. Therefore, when a chassis dynamometer is used, it is more realistic to measure the power absorption horsepower for each vehicle speed without using the equation.

In order to measure the power absorption horsepower, the vehicle is raised to a predetermined vehicle speed on the chassis dynamometer, the gears are neutralized, and the stroke commanded to the accelerator actuator is reduced by a predetermined amount as shown in FIG. Then measure the deceleration. When this deceleration and vehicle speed are included in the equation where We = 0 in the third term of the equation, the power absorption horsepower is calculated. Since the power absorption horsepower determined here includes loss horsepower such as mechanical loss and tire loss, the power absorption horsepower is the steady running horsepower itself. Fig. 5 shows the relationship between the power absorption horsepower (steady running horsepower) and the vehicle speed thus obtained.
Shown in

The steady running horsepower in the case where the power absorption characteristic of the chassis dynamometer does not follow the equation is obtained by interpolation calculation with reference to the table shown in FIG. 5, and only this value and the third term of the equation are calculated. The sum with the calculated acceleration loss horsepower may be calculated as the required horsepower PS in this case.

The required horsepower PS [Ps] obtained during the steady running or the accelerated running is obtained by using the engine speed Ne [rpm] at that time according to the following equation: T = (716.2 / Ne) PS It is converted into an output torque T [kgf], and the relationship between this output torque T and the accelerator actuator stroke that generates this torque is shown in a table.

FIG. 6 shows the contents of this table. If the engine speed is different, the engine output torque changes even for the same stroke. Therefore, in this example, a table is created for three types of engine speed (low speed, medium speed, and high speed). However, if the engine speed does not change significantly even if the vehicle speed differs, only a table for one engine speed is available.

(2) Preparation of a table by teaching friction horsepower This is for determining the braking force at the time of deceleration, and is executed according to a predetermined program similarly to the above (1).

The accelerator actuator is returned to the idling position from a predetermined vehicle speed, and is left at the predetermined gear position. Then, from the deceleration and vehicle speed at that time, deceleration is performed using We = 0 in the third term on the right side of the equation. Calculate horsepower PS _G [Ps]. Steady running in the reduction horsepower PS _G hp PS R _{/ L} [Ps]
(Sum of the first and second terms of the equation), and the value obtained by subtracting this from the following equation F = PS _G −PS _{R / L} ...
And Then, the friction horsepower F and the engine speed Ne are calculated.
Make a table of relationships. However, the deceleration horsepower PS _G in this case, the deceleration of the sign (-) positively replacing, calculated as a positive value.

FIG. 7 shows the contents of the friction horsepower-rotational speed table thus obtained. When the engine speed reaches idling, the vehicle runs idle, and the horsepower in this case becomes the minimum value. This value is also the idle running horsepower whose sign is opposite to the engine friction horsepower. Formula for friction horsepower F
Is calculated, the second term on the right side can also be read from the above-described characteristic of FIG.

(3) Stroke Command Method Using Table Obtained by Teaching In general, in various mode running (for example, 10 mode running or 11 mode running), the relationship between command vehicle speed V and elapsed time is quantified. You can drive as it is.

For this reason, here, the horsepower PS required for the vehicle to travel at the commanded vehicle speed and the change speed is calculated from the given command vehicle speed and the acceleration which is the change speed using an equation. The horsepower PS is converted into an engine output torque T by an equation from the engine speed Ne at that time. From this converted torque T, a stroke is obtained by interpolation calculation with reference to a table of stroke-torque for each of the three types of engine speeds already obtained by teaching,
This stroke is basically commanded to the accelerator actuator. The mode running includes the acceleration, steady state, and deceleration operation modes. In the steady and acceleration modes, a command stroke is given to the accelerator actuator as described above.

When the stroke is commanded in this manner, no error occurs in the stroke commanded to the accelerator actuator unless there is a significant load change under the same conditions of the chassis dynamometer. If it occurs slightly, it is only an error that occurs during interpolation calculation (when interpolation calculation is performed between tables for three types of engine speeds).

When it is necessary to decelerate, unlike the case of acceleration, it is not always possible to decelerate only by operating the accelerator pedal, and a predetermined deceleration may not be possible unless the brake pedal is further depressed. For this reason, when deceleration is required, it must be determined as follows whether to operate only the accelerator pedal or to also operate the brake pedal.

That is, the required horsepower PS when the vehicle must be decelerated has a negative value, and the friction horsepower F acts as an engine brake during deceleration, so this friction horsepower F (calculated as a positive value) is required. If the result added to the horsepower PS is positive or zero, it means that the vehicle speed can be reduced to the commanded vehicle speed only by the engine brake. On the other hand, if the result is negative, it is not possible to decelerate simply by returning the accelerator pedal, and the brake must be depressed by depressing the brake pedal. In other words, in order to determine whether deceleration is possible simply by returning the accelerator pedal, the friction horsepower F is tabulated by teaching in the above (2).

In addition, since the engine output torque is negative in a region where the engine can be decelerated by the engine brake and it is complicated to obtain the negative torque by teaching, a command to the accelerator actuator in this region is obtained by using the following method. Determine the stroke.

First, the friction horsepower F [Ps] at the engine speed Ne at that time is obtained from a table containing the contents of FIG. 7 and the stroke S _N [mm] at no load to obtain the engine speed Ne at that time. Is obtained by interpolation calculation from the table having the contents shown in FIG. The relationship between the engine speed at no load and the stroke can be easily obtained by reading the engine speed at that time while gradually increasing the stroke.

If the required horsepower PS [Ps] calculated from the commanded vehicle speed and the deceleration which is the change speed is negative and the absolute value (| PS |) is smaller than the friction horsepower F, F- | P
Since the accelerator pedal must be returned by the horsepower equivalent to S |, the stroke (this stroke is referred to as _SN ) becomes maximum when PS = 0. On the other hand, F =
In the case of | PS |, idling state (however, play allowance between the accelerator pedal and the accelerator actuator is not included)
That is, since the friction horsepower F is balanced with the required horsepower PS, the stroke is the minimum stroke.

Therefore, if the stroke between the maximum and the minimum strokes is approximated by a straight line, and the stroke S _X [mm] with respect to F- | PS |
S _X is calculated from PS |: F = S _X : S _N by the following equation.

S _X = S _N · (F− | PS |) / F... FIG. 9 illustrates this equation. Point A in the figure gives the maximum stroke and point B gives the minimum stroke. In addition,
The play allowance Si between the accelerator pedal and the accelerator actuator, which changes when the accelerator actuator is installed, is:
A method is considered in which the value is subtracted throughout the entire system and added when a command is given to the accelerator actuator. This play allowance Si corresponds to the value of the stroke immediately before the engine speed starts increasing when the engine is idling by teaching and the stroke is gradually increased. This value is stored as play allowance Si.

FIG. 10 is a routine showing a control operation when the vehicle automatically travels in accordance with a predetermined traveling mode, which is given to the CPU of the personal computer 55.

First, in addition to the engine speed Ne and the actual vehicle speed as feedback data, the command vehicle speed V according to the elapsed time from the start of the mode driving is read by referring to the command vehicle speed data stored in the memory. This command vehicle speed V
Then, the change speed (acceleration or deceleration) α is calculated from (steps 1 and 2).

From the commanded vehicle speed V, the steady running horsepower for this V is determined by interpolation with reference to the table of vehicle speed-steady running horsepower shown in FIG. 5, and is calculated from the steady running horsepower and the third term of the equation. The required horsepower PS is determined from the sum of the acceleration loss horsepower (steps 3 and 4). Further, the friction horsepower F with respect to the engine speed Ne at that time is obtained by interpolation with reference to the horsepower-speed table shown in FIG. 7, and the sum PS + F of the friction horsepower F and the required horsepower PS is calculated ( Steps 5 and 6).

By looking at the values of PS + F and PS, PS + F ≧
If 0 and PS ≧ 0, it is determined that the vehicle must be accelerated or it can be kept in a steady state, and the required horsepower PS is converted into the engine output torque T using the equation from the rotation speed Ne at that time (steps 7 to 9). . Similarly, an acceleration actuator stroke for generating the converted torque is obtained from the rotation speed Ne and the converted torque T by interpolation calculation with reference to a stroke-torque table having the contents shown in FIG.
This command stroke is output to the accelerator actuator (steps 10 and 11).

If PS + F ≧ 0 and PS <0, it is determined that deceleration can be achieved simply by returning the accelerator pedal. The stroke _SN with respect to the engine speed under no load is shown in a table of rotation speed-stroke shown in FIG. determined by reference to interpolation calculation with using the equation obtained by interpolation calculation of the linear approximation command stroke S _X when must decelerated (step 12, 13). If the command stroke S _X is corrected by the difference ΔV between the command vehicle speed V and the actual vehicle speed, it is possible to compensate for a slight displacement of S _X based on linear approximation (step 14).

On the other hand, if PS + F <0, it is determined that the engine brake alone is insufficient and it is not possible to decelerate unless the brake pedal is depressed to apply the brake, and the brake actuator (air cylinder for the brake pedal) is given a predetermined stroke to decelerate. (Steps 7 and 1
5). In this case, the accelerator pedal can be simultaneously returned by a predetermined amount.

Here, the operation of this example will be described.

In this example, prior to automatically running the test vehicle on the chassis dynamometer, the actual vehicle speed, its change speed and the engine speed at that time are used by teaching to determine the vehicle speed and its change speed. The relationship between the engine output torque required for the vehicle to travel and the accelerator actuator stroke that generates this torque is tabulated for each test vehicle and stored in memory.

When entering "automatic traveling", the engine output torque T which must be accelerated or required for steady traveling is obtained from the commanded vehicle speed designated by the traveling mode and its changing speed. The accelerator actuator stroke that generates the torque T is determined by referring to the stroke-torque table.

When this stroke is commanded to the accelerator actuator, and the accelerator pedal is further depressed in accordance with the commanded stroke, a torque is generated according to the request that acceleration must be performed or steady.

The vehicle speed control in this case is open loop control based on table data, and is not feedback control based on actual vehicle speed. Therefore, the work of adjusting the control gain for each test vehicle becomes unnecessary. Chassis dynamometer conditions due to differences in mode driving (weight equivalent to inertia, etc.)
By changing this condition to be able to be entered using a personal computer keyboard,
It can be dealt with simply by setting the conditions of the chassis dynamometer in accordance with various modes of driving.

In other words, the work in which the tester must adjust the control gain for each test vehicle and various modes of travel is replaced with a table creation operation by teaching, and this table creation operation is performed by a personal computer. This significantly reduced the man-hours required for conducting test runs.

Incidentally, in an engine equipped with a warm-up system at the time of starting, even if the accelerator pedal is at the same idling position during warm-up, the engine speed is kept at a predetermined value (for example, 1).
Since the output is increased so as to increase to 500 rpm), during operation of this system, if the command stroke is obtained using a table of stroke-torque obtained by teaching after warm-up, it is difficult to follow the command vehicle speed. Gets worse.

However, even in such a case, the warm-up correction can be performed very easily by the following procedure.
That is, the vehicle travels in the warmed-up engine state, and the generated horsepower PSD [Ps] is obtained from the vehicle speed at that time by interpolation using a table having the contents shown in FIG.
In a table together with the elapsed time t from the start. If this PSD is assumed to be PSD (t) as a function of time t, the horsepower deviation PSH [Ps] t seconds after the start is calculated by the following equation. PSH = PS-PSD (t) ...

Therefore, in the case of the traveling mode starting from the start of the engine, the warm-up correction may be performed by adding the deviation PSH to the required horsepower PS in step 9 in FIG. However, since PSD (t) in the equation also changes depending on running conditions, it is more practical to change in each mode.

On the other hand, in the deceleration running mode, it is determined whether the vehicle can be decelerated only by the engine brake or not, and if it is insufficient, the brake must be further braked.
The braking by the brake pedal is performed only when the vehicle cannot be decelerated only by the engine brake. This prevents useless braking and reduces the chances of wearing the braking mechanism.

Further, even if it is possible to decelerate only by the engine brake, obtaining a negative engine output torque by performing a complicated calculation from the required horsepower having a negative value may deteriorate the response and complicate the device. However, when the command stroke at the time of deceleration is obtained by the approximate calculation using the formula as in this example, troublesome calculation is not required, thereby maintaining the responsiveness of the device and improving the device response. Can be simplified.

Here, the case of the mode running has been described.
In addition to the mode traveling, comparison of various power performances of the vehicle in the on-vehicle state can be easily performed by changing the command vehicle speed data accordingly.

In a vehicle equipped with an automatic transmission, when the driver overtakes or runs short of power while driving in the D range, if the accelerator pedal is strongly depressed, the gear is automatically lowered by one step to increase the vehicle speed. A mechanism is provided. This mechanism works in each range, but at high vehicle speeds ATF
(Automatic transmission fluid) is often not kicked down to avoid overheating.

By the way, if this mechanism also works at the time of creating a torque-stroke table, it becomes impossible to find the relationship between the engine output torque and the accelerator actuator stroke on the high load side in the low and middle rotation range as shown in FIG. . In other words, if this relationship is not known, it is not possible to create a torque-stroke table for the low to middle rotation range, and therefore, for a vehicle equipped with an automatic transmission in which kick down works, it is possible to automatically perform vehicle speed control. You will not be able to.

It is conceivable that the vehicle is driven in the first or second speed range so that kick down does not work. However, in this case, the engine speed greatly changes due to slippage of the torque converter on the high load side. It is not possible to run at 1st or 2nd speed.

Therefore, in this example, a table of the torque-stroke for the low and middle rotation range where the kick-down works is prepared by extrapolating the table value of the torque-stroke for the high rotation range where the kick-down does not work. Briefly, torque to a predetermined high rotational speed N ₁ - the relation of stroke, the engine is determined in advance rotational speed - torque
Torque to the output characteristic correction coefficient and 8 the predetermined low rotational speed N ₂ and medium engine speed N ₃ by moving and corrected by using a table of idling speed strokes whose content was calculated from the relationship - Stroke Ask for a relationship.

FIG. 12 shows a general engine speed-torque.
The output torque increases as the rotation speed increases starting from the idling rotation speed.The output torque reaches a peak at a predetermined rotation speed, and the torque decreases even if the rotation speed is increased beyond that. .

From this characteristic, the maximum torque is set as 1.
Assuming that the output torque is 1.0, the output torque obtained for an arbitrary rotation speed from the rotation speed at the maximum torque to the idle rotation speed is set to 1.0.
Convert to the following values. This converted value is referred to as a correction coefficient K.

At this point, the above-mentioned high rotation speed N _{1 is set} to 350
0 rpm, low rotational speed N ₂ to select the 800rpm idle rotation, when the correction factor of the two relative to the rotational speed N _1, N ₂ and K _1, K _2, which are determined from the characteristics of FIG. 12.

When the two correction coefficients K ₁ and K ₂ are obtained in this way, even if the output torque for the low rotation speed N ₂ cannot be measured, the output torque for the high rotation speed N _{1 is} multiplied by (K ₂ / K ₁ ). there can be substantially estimated If it is the output torque for low rotational speed N _2.

On the other hand, when N ₁ and N ₂ are engine speeds at no load and the accelerator actuator strokes S ₁ and S ₂ for these N ₁ and N ₂ are obtained from the characteristics shown in FIG.
_1, S ₂ (see FIG. 11) in which from the point of 0 engine output torque, respectively, a curve (shown by a solid line) for a high rotational speed N ₁ in FIG. 13, S ₁ as shown by the dashed line
-S ₂ only moves in parallel to a small stroke direction matching the zero point torque. When the value of this translated curve is further corrected by multiplying it by (K ₂ / K ₁ ), the characteristic of the torque-stroke with respect to the low rotational speed N ₂ is obtained as shown by the broken line.

[0079] In the same manner, selecting the rotational speed N ₃ in a given a high rotational speed N ₁ and the low-speed and N ₂ of the intermediate 2150 rpm, the correction factor K ₃ for medium engine speed N ₃ is the characteristic of FIG. 12 accelerator actuator stroke S ₃ is obtained in decreasing the characteristics of FIG. 8 also for the medium engine speed N _3, this time the curves for high rotational speed N ₁ is translated to a small stroke direction by S ₁ -S _3, further K ₃ / correcting over K _1, the torque with respect to medium engine speed N ₃ - can be obtained the properties of the stroke as indicated by the broken line in FIG. 13.

Actually, the relationship between the correction coefficient K and the engine speed N shown in FIG. 12 is stored in a table in advance, and K _{1 is} calculated by interpolation calculation of this table.
The ~K _3, also idling speed to Figure 8 the content - seeking S ₁ to S ₃ of the table of stroke by interpolating calculation, the high rotational speed torque to the N ₁ - parallel above the value of the stroke table by adding the operation corresponding to the movement correction, a low rotational speed N _2, for medium engine speed N ₃ torque - it is created to store a table of the stroke.

When the vehicle equipped with the automatic transmission is to be driven in the mode in the low and middle rotation range, the command stroke to be given to the accelerator actuator is determined from the table containing the broken line in FIG.

As described above, the relationship between the torque and the stroke with respect to the high rotation range obtained by the teaching is obtained in advance.
Calculated from the relationship between the engine speed and torque
If the relationship between the torque and the stroke for the low to middle rotation range is determined by moving and correcting using the relationship between the force characteristic correction coefficient and the no-load rotation speed-stroke, a vehicle having an automatic transmission in which kick-down works can be obtained. Also, similarly to a vehicle having a manual transmission, mode traveling can be automatically performed, and the vehicle speed can follow the commanded vehicle speed.

Here, the two rotation speeds N ₂ and N ₃ are represented from the low to middle rotation range. However, the present invention is not limited to this. By increasing the number as far as the memory capacity permits, The tracking accuracy of the vehicle speed control can be improved.

If N _{1 to} N ₃ are determined from the beginning, there is no need to create a table having the contents shown in FIG. 12, and K _{1 to} K ₃ can be stored directly in the memory or the keyboard can be used. More input can be made.

Also, for a vehicle equipped with a manual transmission, if the torque-stroke characteristic for the high rotation range determined by actual measurement is moved and corrected, the torque-stroke characteristic for the low and middle rotation range is determined. Compared with the case where the characteristics of the torque-stroke for the low-medium rotation range are also measured and obtained, the time for creating the torque-stroke table can be significantly shortened.

[0086]

According to the first aspect of the present invention, the relationship between the engine output torque and the axle actuator stroke for generating this torque in the high rotation range by teaching is shown in a table for a vehicle in which the kick down mechanism works in the low and middle rotation ranges. In addition, this relationship is defined as a no-load rotation speed-stroke number table and a previously obtained engine rotation speed-total.
When moving and correcting using the output characteristic correction coefficient calculated from the relationship of the torque and calculating the torque-stroke relationship for the low and middle rotation range and setting it in a numerical table, and entering automatic driving according to the command vehicle speed data, When the acceleration must be accelerated or steady, the command stroke is determined by selecting and using the torque-stroke number table according to the rotational speed at that time, so that the man-hours required for performing a test run is greatly reduced. At the same time, even in a vehicle equipped with an automatic transmission in which kickdown works, the mode traveling can be automatically performed similarly to a vehicle equipped with a manual transmission, and the vehicle speed can follow the commanded vehicle speed.

In the second invention, the relationship between the friction horsepower of the engine and the engine speed is set as a table by teaching for a vehicle that performs a kick-down in the low to middle speed range. Is used to determine whether or not deceleration is possible only with the engine brake, so that only when the deceleration cannot be achieved with only the engine brake, braking is performed with the brake pedal, and the engine output torque and this torque for the high rotation range are generated by teaching. The relationship between the accelerator actuator strokes is set in a numerical table, and this relationship is calculated by using the no-load rotational speed-stroke number table and the engine calculated in advance.
Using the output characteristic correction coefficient calculated from the rotational speed-torque relationship, the torque-stroke relationship for the low-medium rotational speed range is obtained and corrected into a numerical table. Accordingly, when entering automatic driving, if the engine can be decelerated only by the engine brake, the command stroke is determined by selecting and using the torque-stroke table according to the rotational speed at that time, so that unnecessary braking can be prevented. In addition to the above, even in a vehicle equipped with an automatic transmission in which kickdown works, the mode traveling can be automatically performed similarly to a vehicle equipped with a manual transmission, and the vehicle speed can follow the commanded vehicle speed. .

[Brief description of the drawings]

FIG. 1 is a diagram corresponding to a claim of the first invention.

FIG. 2 is a diagram corresponding to claims of the second invention.

FIG. 3 is a waveform diagram showing a vehicle speed change when an accelerator actuator stroke is increased and changed.

FIG. 4 is a waveform diagram showing a change in vehicle speed when an accelerator actuator stroke is decreased and changed.

FIG. 5 is a characteristic diagram showing a table of power absorption horsepower with respect to vehicle speed.

FIG. 6 is a characteristic diagram showing table contents of an engine output torque with respect to an accelerator actuator stroke.

FIG. 7 is a characteristic diagram showing a table of friction horsepower with respect to an engine speed;

FIG. 8 is a characteristic diagram showing the contents of a table of an accelerator actuator stroke with respect to the engine speed at the time of no load.

FIG. 9 is a characteristic diagram for explaining a method of obtaining an accelerator actuator stroke when deceleration is required.

FIG. 10 is a flowchart illustrating a control operation.

FIG. 11 is a characteristic diagram showing a relationship between an accelerator actuator stroke and an engine output torque when kick down is applied.

FIG. 12 is a characteristic diagram of general engine output torque with respect to engine speed.

FIG. 13 is a characteristic diagram showing the contents of a table of engine output torque with respect to an accelerator actuator stroke for a vehicle including an automatic transmission in which kickdown works.

FIG. 14 is an overall configuration diagram of a conventional example.

FIG. 15 is a flowchart of a main control unit in a conventional example.

FIG. 16 is a schematic diagram for explaining position control of a conventional air cylinder.

FIG. 17 is a detailed view of a conventional solenoid valve unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Accelerator pedal 2 Accelerator 3 Vehicle speed sensor 4 Change speed calculation means 5 Engine speed sensor 6 Stroke-torque number tabulation / storage means 8 Command vehicle speed data storage means 9 Change speed calculation means 10 Required horsepower calculation means 11 Acceleration / steady state judgment Means 12 Torque conversion means 13 Stroke calculation means 14 Stroke command means 15 No-load rotation speed-stroke number tabulation / storage means 16 Moving / correction means 17 Stroke-torque number tabulation / storage means 21 Brake pedal 22 Brake actuator 23 Horsepower- Number of revolutions tabulation means 24 Horsepower-Number of revolutions tabulation / storage means 25 Friction horsepower calculation means 26 Deceleration judgment means 27 Sum calculation means 28 Judgment means 29 Stroke calculation means 30 Stroke calculation means 31 Stroke command means 42 Accelerator pedal 43 B Kipedaru 46 air cylinder 48 solenoid valve unit 49 solenoid valve driving circuit 50 microcomputer 55 personal computer

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) G01M 17/00 F02D 29/02 F02D 45/00

Claims (5)

(57) [Claims] In a vehicle equipped with an automatic transmission in which a kick-down mechanism works in a low-medium rotation range, an accelerator actuator that drives an accelerator pedal according to a command stroke, a sensor that detects a vehicle speed, and a change speed of the vehicle speed are provided. Means for calculating, a sensor for detecting the number of revolutions of the engine,
Means for storing in a numerical table the relationship between the output torque of the engine for a high rotation range and the axle actuator stroke for generating this torque using the vehicle speed, the speed of change thereof, and the engine speed at that time by teaching, means for storing in the numeric table the relationship between the rotational speed and the accelerator actuator stroke at the time of no load, the idling speed - relationship stroke and
Calculated from the relationship between engine speed and torque obtained in advance.
Means for moving and correcting the torque-stroke relationship with respect to the high rotational speed range using the output characteristic correction coefficient thus obtained to obtain the torque-stroke relationship with respect to the low-medium rotational speed range, and means for storing this relationship as a numerical table Means for storing in advance the command vehicle speed data, means for calculating the change speed of the command vehicle speed, means for calculating the horsepower required for the vehicle to travel at the command vehicle speed and the change speed, and the required horsepower Means for judging whether the vehicle must be accelerated or steady, and if the result of the judgment indicates that the vehicle must be accelerated or steady, the required horsepower is converted into an engine output torque based on the engine speed at that time. And a plurality of accelerator strokes for generating the converted torque according to the rotation range at that time. Means for calculating selected and used any number table click, automatic driving apparatus for a vehicle, characterized in that it comprises means for commanding the stroke to the accelerator actuator. 2. A vehicle equipped with an automatic transmission in which a kick-down mechanism works in a low to middle rotation range, wherein an accelerator actuator drives an accelerator pedal according to a command stroke, and a brake actuator drives a brake pedal according to a command stroke. , A sensor for detecting the vehicle speed,
Means for calculating the speed of change of the vehicle speed, a sensor for detecting the engine speed, and the vehicle speed by teaching,
Means for storing in a numerical table the relationship between the output torque of the engine and the axle actuator stroke for generating this torque in a high rotation range using the speed of change and the engine speed at that time; Means for storing the relationship between the number and the accelerator actuator stroke in a numerical table;
Stroke relationship and engine rotation required in advance
Means for moving and correcting the torque-stroke relationship for the high rotation range using the output characteristic correction coefficient calculated from the number-torque relationship to determine the torque-stroke relationship for the low-medium rotation range; Means for storing in a table, means for storing the relationship between the friction horsepower of the engine and the engine speed in the form of a table using the vehicle speed, the change speed thereof and the engine speed at that time by teaching, and the engine at that time Means for calculating the friction horsepower with respect to the number of revolutions using the horsepower-number of revolutions table, means for storing data of the commanded vehicle speed in advance, means for calculating the change speed of the commanded vehicle speed, Means for calculating the horsepower required for the vehicle to travel at the changing speed, means for determining whether the vehicle must be decelerated from the required horsepower, Means for calculating the sum of the required horsepower and the friction horsepower when necessary, and means for judging, based on the sum, whether the vehicle can be decelerated only by the engine brake or cannot be decelerated by the engine brake alone. Means for calculating a predetermined stroke for the accelerator actuator by selecting and using one of the plurality of stroke-torque tables when the deceleration can be performed only by the engine brake based on the determination result; and And a means for calculating a predetermined stroke with respect to the brake actuator when the engine brake cannot decelerate, and a means for instructing the brake actuator with this stroke. 3. A torque-stroker for the low-medium rotation range.
The means for determining the relationship between the torques is the no-load speed-stroke
And the output characteristics in the high speed range
Low and medium speed calculated from the relationship between engine speed and torque
Using the output characteristic correction coefficient of the shift range for the high speed range
Movement / correction of torque-stroke relationship to low / mid rotation range
2. The torque-stroke relationship with respect to the torque is calculated.
Or the automatic driving device for a vehicle according to 2. 4. A torque-stroker for the low to middle rotation range.
The means for determining the relationship between the torques is the no-load speed-stroke
DOO upon relationship and advance sought substantially full load of high rpm
Calculated from the torque value and the torque value at almost full load in the low and middle rotation range
Using the corrected output characteristic correction coefficient,
Moves and corrects the relationship between the torque and the stroke to achieve a low to medium rotation range
And calculating a torque-stroke relationship with respect to the torque.
3. The automatic driving device for a vehicle according to 2. 5. The torque as the number of revolutions in the high revolution range is
5. The method according to claim 1, wherein the rotational speed is set to a substantially maximum value.
An automatic driving device for a vehicle according to one aspect .