JP2002318527A - Drive simulator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drive simulator in which a picture in a smooth moving state can be obtained without causing shakes of viewpoint or unwanted vibration of a virtual vehicle on display even when discontinued parts appear between polygons adjacent to each other in a simulated space. SOLUTION: The drive simulator is provided with a means for displaying a simulated field of vision by polygons to a user on the basis of input information based on the user's operation to an input device, position information of a virtual vehicle in a simulated space and simulated background information. Smoothing processing is carried out on the difference in level 50 using a primary delay expression from the height h and j of the adjacent polygons 60 and 62, and the own vehicle 7 is displayed with the height controlled so as to move along a curve 64 generated by the smoothing processing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a simulated driving device for displaying a running scene as an image on a display device based on a user's steering operation of a simulated vehicle so that the user can simulate a running state.

[0002]

2. Description of the Related Art Conventionally, a simulated two-wheeled vehicle in which a user can perform various operations and a display device using a CRT or the like for displaying a desired image including a traveling path relating to a running state of the simulated two-wheeled vehicle are combined. The device is provided for use in games or for driving education of motorcycles.

[0003] These simulated driving devices are used by combining polygons with an image displayed to a user. Various methods for controlling the polygon have been proposed. For example, a polygon data conversion device and a three-dimensional simulator device that can effectively use hardware or the like that does not draw a back polygon are disclosed in JP-A-8-6465. I have. Also, among multiple raster engines,
The processing load distribution method of the image generating apparatus, which distributes the processing load evenly without concentrating the load of the two-dimensional polygon information processing on a certain raster engine and enables effective use of processing resources, is disclosed in 8-335273.

[0004]

In a simulated driving apparatus, for example, when the vehicle (for example, a viewpoint in the case of subjective view, an image of the vehicle in the case of objective view) expresses up and down a hill or the like, the terrain is not suitable. Are sequentially referred to, and the height and attitude of the viewpoint and the own vehicle are obtained and displayed. In this case, since the terrain is defined by a polyhedron combining polygons, the angle and height of the terrain become discontinuous when moving to adjacent polygons, and the viewpoint and the height and attitude of the vehicle become smooth. No.

In other words, the screen display fluctuates due to the effect of the viewpoint coordinates being affected by discontinuous portions between adjacent polygons, or the display in which the coordinates of the own vehicle are affected by the discontinuous portions and the own vehicle vibrates unnecessarily. There is a problem that it becomes.

[0006] These movements can be obtained by using a method of dividing polygons into small parts and reducing changes in angles and heights, and a method of solving equations of motion such as tires and suspensions. However, in each case, the calculation load increases.

The present invention has been made in view of such a problem. Even if there is a discontinuity between adjacent polygons in the simulation space, the viewpoint does not fluctuate and a virtual vehicle is unnecessary. It is an object of the present invention to provide a simulated driving device capable of obtaining a smooth running image without causing vibration.

Another object of the present invention is to provide a display capable of obtaining an image of a smooth running state in a simulated space without being affected by discontinuous portions between adjacent polygons. An object of the present invention is to provide a simulated driving device that can be realized at low cost without increasing the weight of the simulated driving device.

[0009]

A simulated driving device according to the present invention also includes input information based on a user operation on an input device, position information of a virtual vehicle in a simulated space, and simulated background information. In the simulated driving device including means for displaying a simulated field of view to the user by the polygon, information calculated by using a first-order lag equation from the terrain display polygon and the first information of the virtual vehicle. And a means for generating an image of the virtual vehicle from information obtained by the smoothing calculation means.

Here, the image of the virtual vehicle is an image viewed from a viewpoint set in the virtual vehicle in subjective view, and an image viewed from a viewpoint set behind the virtual vehicle in objective view. .

As a result, in the simulation space, a discontinuous portion between adjacent polygons is converted into a smooth curve,
The virtual vehicle (including the viewpoint) moves along this curve. Therefore, it is possible to obtain a smooth running state image without causing the viewpoint to fluctuate and unnecessary vibration of the virtual vehicle on display.

In addition, since the processing of the first-order lag equation, which is light in calculation, is performed, the movement of the virtual vehicle can be smoothed without affecting the real-time three-dimensional image operation display. This is also advantageous in reducing the cost for software development.

By the way, the vibration characteristics change depending on the spring and the damper used in the suspension of the automobile or the like. If the damping is weak, the motion becomes a sinusoidal motion that attenuates when descending a step. By adjusting the damping force, a motion close to the critical damping of the suspension can be obtained.

Since the aspect of the motion close to the critical damping is similar to the waveform of the first-order lag, the expression close to the critical damping of the suspension can be performed when the vehicle passes through the step due to the adjacent polygon. Thus, the user can obtain a realistic atmosphere as if he / she is riding in a real vehicle.

In this case, the first information may include information on a height of the virtual vehicle in the simulation space, or information on a tilt of the virtual vehicle in a traveling direction in the simulation space. May be provided. Further, the first information may include information on a tilt in a direction perpendicular to a traveling direction of the virtual vehicle in the simulation space.

Further, in the present invention, the number of smoothing in the first-order lag equation may be variable. As a result, it is possible to change the result of the smoothing processing, and it is possible to express various hardnesses of the suspension.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a simulated driving device according to the present invention will be described below with reference to FIGS.

First, the simulated driving device 2 according to the present embodiment
As shown in FIG. 1, a simulated vehicle 4 having a shape that allows the user 20 to get on the vehicle and outputting various information based on the operation of the occupant 20, and output information from the simulated vehicle 4. Simulated vehicle 4 on which the user 20 is riding based on
Based on the position information of the virtual vehicle 7 (see FIG. 10; hereinafter, simply referred to as the own vehicle 7) in the simulation space and the simulated background information corresponding to the It has a display box 6 for displaying a simulated field of view, and a control circuit 22 for managing and controlling the simulated vehicle 4 and the display box 6.

The display box 6 has a display 24 for displaying a simulated view to the user 20;
A CGI generator that holds a background image constituting a simulated field of view based on various information from the simulated vehicle 4 and object data of the host vehicle 7 and displays the simulated field of view on the display 24 based on information from the control circuit 22. (Comput
er Generated Image) 26 and a speaker unit 28 for transmitting a sound generated by a steering operation or another vehicle to the user 20.

As shown in FIG. 2, the simulated vehicle 4 includes various sensor groups such as a steering wheel torque sensor 30, an accelerator opening sensor 32, and brake pressure sensors (34, 36), and a lighting switch 38, as in the actual vehicle. Switches such as the turn signal switch 40 and the pitch motor 4
2. Various motor groups such as a steering motor 44 are provided. FIG. 2 illustrates typical examples of the above-described various sensor groups, switch groups, motor groups, and the like, and a description thereof will be omitted.

On the other hand, the control circuit 22 includes a CPU as a central processing unit for performing various calculations, determinations and controls, and an RO as a storage means for storing a system program and the like.
M and RAM as storage means used for work and the like
Etc. Of course, display control for the display 24 is also performed based on information from various sensor groups and switch groups.

The information transmitted from the control circuit 22 is basically the current position data, the current speed data, the current acceleration data, etc., related to the steering operation of the simulation vehicle 4.

The CGI generator 26 generates video information of a pre-stored traveling road including a landscape as the various data from the control circuit 22 is input, for example, in units of frames. Indicates a simulated field of view.

Next, a simulation space including a simulation field of view will be described. The video information of the traveling road including the landscape is all expressed in a simulation space, and the simulation space is a three-dimensional space having an x-axis, a y-axis, and a z-axis in the control circuit 22 as shown in FIG. Is calculated. Also, since the xy plane corresponds to the bottom surface in the simulation space as shown in FIG.
The z coordinate will correspond to the height in the simulation space.

That is, video information such as a building and a traveling road expressed in the simulation space is composed of information of a large number of polygons, and the information of each polygon has vertex data. The vertex data includes three-dimensional coordinates in the simulation space. For example, the three-dimensional coordinates are sequentially calculated according to an operation input from the simulation vehicle 4, and, for example, an image in which the own vehicle 7 moves is displayed. become. The vertex data of these polygons is stored in the RAM of the control circuit 22 or the CGI generator 2.
6 is stored in the RAM or the like.

In the display of a building or a traveling road using such polygons, when the polygons are roughly set (set with large polygons), the inclination between adjacent polygons is reduced as shown in FIGS. 10 and 11, for example. 9 corners
A step 50 set to 0 ° will occur. When the host vehicle 7 is caused to travel in the form of the arrangement relation of polygons (hereinafter, referred to as a first form) in which the step 50 occurs, the step 50 is generated.
The running state becomes discontinuous at the part, giving an unnatural impression.

Therefore, in the present embodiment, in order to smooth the inclination angle of the step 50 in the above-described first embodiment, interpolation is performed using a first-order lag equation described later. In addition to the steps shown in FIGS. 10 and 11 described above, as shown in FIGS. 13 and 14, there are polygons that are inclined at a certain angle with respect to the traveling direction of the host vehicle 7 (host vehicle 7). Form in which two polygons adjacent to each other in the running direction are bent at the boundary portion thereof:
16 and FIG. 17 and FIG. 17, where there is a polygon that is inclined at an angle with respect to a direction perpendicular to the traveling direction of the vehicle 7 (adjacent in the traveling direction of the vehicle 7). A form in which two polygons have a twist relationship: hereinafter, referred to as a third form).

Next, the simulated driving device 2 according to the present embodiment
The equation of the first-order lag used in will be described.

First, the equation of the first-order lag is a recurrence equation such as the following equation (1).

[0030] In _{a n + 1 = (ka n} + b) / (k + 1) ... (1) Equation (1), k is a positive value in the smoothing coefficient,
n is an integer of 0 or more. It can be seen that the sequence {a _n } determined from equation (1) converges to b for an arbitrary first term a ₀ when k> − ／.

Here, an example of the expression of the first-order lag will be described with reference to FIGS. The vertical axis of the graph of FIG. 5 and FIG. 6 represents a _n, the horizontal axis represents n.

FIG. 5 is a graph determined from the recurrence formula expressed by the following formula (2), where the first term a ₀ = 5, b = 0, and the smoothing coefficient k is 20.

[0033] _{a n + 1 = (20a n} +0) / (20 + 1) = (20/21) a n ... (2) The (2) sequence {a _n} from the equation geometric progression of common ratio 20/21 It turns out that it decreases monotonically from the first term 5 and converges to 0.

FIG. 6 shows that the smoothing coefficient k is reduced,
It is a graph when k = 5 as in the following equation (3).

[0035] _{a n + 1 = (5a n} +0) / (5 + 1) = (5/6) a n ... (3) geometric progression of the sequence {a _n} is the common ratio 5/6 by the equation (3) It can be seen that, as in the case of Expression (2), the first term monotonically decreases from 5, and converges to 0. Thus, these two curves can be used as a smooth trajectory for moving a polygon having a step determined by the first term a ₀ = 5.

By the way, it is known that the vibration characteristics are changed by a spring and a damper used for a suspension of an automobile or the like. If the damping is weak, the motion becomes a sinusoidal motion that attenuates when descending a step. By adjusting the damping force, a motion close to the critical damping of the suspension can be obtained.

Since the behavior of the motion close to the critical damping is similar to the waveform of the first-order lag, the host vehicle 7 can use the first-order lag equation such as the above-mentioned equation (1) to move the vehicle 7 to the adjacent polygon. When passing through a step due to the suspension, an expression close to the critical damping of the suspension can be performed.

As is clear from the graphs of FIGS. 5 and 6, it can be seen that the expression (3) converges faster than the expression (2). That is, the smaller the smoothing coefficient is, the more the sequence ｛a
_n収束 converges rapidly.

Therefore, it is understood that the hardness of the suspension can be expressed by changing the value of the smoothing coefficient. For a soft suspension, see FIG.
In the case of a hard suspension, the smoothing coefficient may be reduced as shown in FIG.

Next, a flowchart of the common function A for calculating the above-described sequence {a _n } will be described. Here, the function means a program that performs a certain process, such as the usage in the C language. The function for calculating a sequence {a _n},
a corresponding to a _n and b corresponding to b in equation (1)
And the number of skips r described later and the smoothing coefficient k of 4
It has two arguments and performs a process of returning a value corresponding to the calculated an _{+ r} as a return value.

FIG. 7 is a flowchart of the common function A. Arguments a, b, r, and k are received in step S101, and a loop counter n is initialized to 1 in step S102. Steps S103 to S105 form a loop process. Loop termination condition is n> r or a
= B.

Here, r is a value used to return the r-th value from the argument a. This is because when the speed of the host vehicle 7 is high, for example, every tenth value is required as the height data used for display, such as a black circle plotted on the curve shown in FIG. If the speed is slow, FIG.
In some cases, every fifth value is required. The value of the skip count is r.

A = b which is another end condition of the loop
This is because, when a = b, the value obtained by the calculation from now on will not change from b due to the property of equation (1). This is because b is the limit value in the equation (1), and theoretically, the sequence {a _n } in the equation (1) may be a = b except that the first term is b. Although it cannot be obtained, the error may be rounded due to the calculation by the computer, and may coincide with the limit value b.

Returning to the description of the flowchart of FIG. 7, in step S103, calculation is performed according to equation (1), and in step S104, the loop counter is incremented, and the processing in the loop ends. This processing is performed until the termination condition determined in step S105 occurs, and the value of a is returned in step S106, which is the next processing after the loop is completed, whereby the processing of the common function A ends. As described above, although the common function A is a process for calculating a first-order lag equation, it is understood that the process is a process with a lighter load as compared with calculation of a motion equation of a suspension or the like.

Next, with respect to the above-described first to third embodiments,
A method of realizing a smooth movement of the host vehicle 7 by using the above-described first-order lag equation will be described with reference to FIGS.

First, using the common function A described above, the first
Will be described with reference to FIGS. 10 to 12.

FIG. 10 is an explanatory view showing the host vehicle 7 passing through the step 50 in the first embodiment, and FIG.
FIG. 5 is an explanatory diagram in which the side surface of the own vehicle 7 of FIG. As can be seen from FIG. 11, the height of the polygon 60 on which the vehicle 7 is riding is h,
Is j.

Here, the flowchart of FIG. 12 will be described. The outline of the process is a process of substituting h into the first term in equation (1) and substituting j into b, and sequentially setting the obtained values to the height of the host vehicle 7.

In step S201, the current height h of the host vehicle 7 is determined. Here, the height of the host vehicle 7 is the polygon 60
X from the coordinates of the bottom of the wheel at the moment when
-The length of the perpendicular when the perpendicular is lowered on the y-plane, that is, the value of the z coordinate at the bottom. In the next step S202, the height j of the polygon 62 to be transferred is determined. This height is the value of the z-coordinate of the polygon 62 to which the wheel moves.

In step S203, h and j obtained in steps S201 and S202 are substituted for variable a serving as an argument, and j is substituted for variable b serving as an argument. The next step S204 to step S207 is a loop process, and the continuation condition is a period during which the height of the host vehicle 7 is controlled using a first-order lag equation.

In step S204, the process starts with the common function A using the number of skips r, a and b according to the desired smoothing coefficient and the speed of the host vehicle 7 as arguments. Since the processing by the common function A has been described above, a duplicate description thereof will be omitted here.

In the next step S205, the return value from the common function A is substituted into a again, and the step S2 is executed.
At 06, a is reflected on the height of the host vehicle 7. Then, by repeating this loop processing, the own vehicle 7 becomes
Move along the symbolized and smoothed curve 64, and when the continuation condition of step S207 is satisfied, the processing for the first embodiment ends.

Next, using the common function A described above, the second
Will be described with reference to FIGS. 13 to 15.

First, the inclination in the traveling direction of the host vehicle 7 in the second mode, that is, the mode in which the polygon 68 is inclined at an angle with respect to the traveling direction of the host vehicle 7, For example, when the direction vector of the traveling direction of the vehicle 7 at the moment when the vehicle transits from the polygon 66 to the adjacent polygon 68 is set to (a, b, c), c / √ (a ² + b ²⁾ ).

When the host vehicle 7 moves in the direction of the vector 12 on the polygon 68, the vector 12
Is set to (s, t, u), the inclination of the polygon 68 may be defined as u / √ (s ² + t ² ).

Here, the flowchart of FIG. 15 will be described. In this flowchart, the inclination of the own vehicle 7 in the traveling direction is m, and the inclination of the polygon 68 to which the host vehicle 7 moves is p. The outline of the process is a process of substituting m for the first term and substituting p for b in Expression (1), and sequentially setting the obtained values to the inclination of the host vehicle 7.

In step S301, the inclination m of the current traveling direction of the host vehicle 7 is obtained, and in the next step S302, the inclination p of the polygon 68 to which the host vehicle 7 moves is obtained.

In steps S301 and S302, m and p are determined, and in step S303, m is substituted for a variable a serving as an argument, and p is substituted for a variable b serving as an argument. Steps S304 to S307 are loop processing, and the continuation condition is a period during which the inclination of the own vehicle 7 in the traveling direction is controlled using the first-order lag equation.

In step S304, the process starts with the common function A using the number of skips r, a, and b according to the desired smoothing coefficient and the speed of the host vehicle 7 as arguments. Then, in the next step S305, the return value from the common function A is substituted into a again, and in step S306, a is reflected on the inclination of the host vehicle 7. Then, by repeating this loop processing, the own vehicle 7 moves to the adjacent polygon 66.
, And 68 along a smoothed curve (not shown), and when the continuation condition of step S307 is satisfied, the processing for the second embodiment ends.

Next, using the common function A described above,
The smoothing process for the embodiment will be described with reference to FIGS.

First, the inclination in the direction perpendicular to the traveling direction of the host vehicle 7 in the third mode, that is, the mode in which the polygon 72 is inclined at a certain angle with respect to the direction perpendicular to the traveling direction of the host vehicle 7, Is the lateral inclination (kant) of the host vehicle 7, and for example, when the direction vector of the rotation axis of the rear wheel of the host vehicle 7 is set to (a, b, c), c / √ (a ² + b ² )
May be determined. In addition, the direction of the direction vector is determined in advance in one of the right and left directions and the left and right directions of the vehicle 7.

The adjacent polygon 70 shown in FIG.
And 72, the vector 16 on the polygon 72 to which the host vehicle 7 moves is set as the traveling direction of the host vehicle 7, and the vector 18 perpendicular to the traveling direction is set as the inclination of the polygon 72. When the vector 18 is set to (s, t, u), the inclination of the polygon 72 may be defined as u / √ (s ² + t ² ).

Here, the flowchart of FIG. 18 will be described. In this flowchart, the vertical inclination of the traveling direction of the vehicle 7 is m, and the inclination of the polygon 72 to which the host vehicle 7 moves is p. The outline of the process is a process of substituting m for the first term in equation (1), substituting p for b, and sequentially determining the obtained values in the vertical direction of the traveling direction of the vehicle 7.

First, in step S401, the current vehicle 7
Of the moving direction of the polygon 72 is obtained, and in the next step S402, the inclination p of the polygon 72 to be transferred is obtained.

In steps S 403, m and p are substituted for the gradients m and p obtained in steps S 401 and S 402, and p is substituted for a variable b serving as an argument. Steps S404 to S408 are loop processing, and the continuation condition is a period in which the inclination of the host vehicle 7 in the traveling direction in the vertical direction is controlled using the primary delay equation.

In step S404, the process of the common function A is started with the number of skips r, a, and b corresponding to the desired smoothing coefficient and the speed of the host vehicle 7 as arguments. Then, in the next step S405, the return value from the common function A is substituted into a again, and in step S406, a is reflected on the inclination of the host vehicle 7. Then, by repeating this loop processing, the own vehicle 7 can move adjacent polygons 70 and 72
It moves along a smoothed curve (not shown) between the two, and when the continuation condition of step S407 is satisfied, the processing for the third embodiment ends.

As described above, by using the first-order lag equation for the first to third forms of adjacent polygons, the discontinuous portion between adjacent polygons becomes a smooth curve in the simulation space. The converted vehicle 7 (including the viewpoint) moves along the curve. Therefore,
On the display, a smooth running image can be obtained without causing the viewpoint to fluctuate and unnecessary vibration of the vehicle 7.

Further, since the calculation is performed using a formula of the first-order lag, which is light in terms of calculation, the movement of the host vehicle 7 can be made smooth without affecting the real-time three-dimensional image operation display. . This is also advantageous in reducing the cost for software development.

Since the behavior of the vehicle suspension near the critical damping is similar to a first-order lag waveform,
When the own vehicle 7 passes through a step formed by adjacent polygons, an expression close to the critical damping of the suspension can be performed, and the user can obtain a realistic atmosphere as if he / she is riding in a real vehicle. .

Further, since the number of smoothing of the first-order lag equation is variable, it is possible to change the result of the smoothing process.
The hardness of various suspensions can be expressed.

As described above, in the simulated driving apparatus according to the present embodiment, it is possible to smooth the discontinuous angle and height between adjacent polygons, and to move the own vehicle 7 smoothly. Becomes

The simulated driving device according to the present invention is not limited to the above-described embodiment, but may adopt various configurations without departing from the gist of the present invention.

[0073]

As described above, according to the simulated driving apparatus of the present invention, even if there is a discontinuity between adjacent polygons in the simulated space, the display does not need to be shaken or a virtual vehicle is not required. It is possible to obtain an image of a smooth running state without causing any vibration.

Further, in the simulation space, a display capable of obtaining an image of a smooth running state without being affected by discontinuous portions between adjacent polygons can be provided at a low cost without increasing the calculation load. Can be realized.

[Brief description of the drawings]

FIG. 1 is a side view of a simulation driving apparatus according to the present embodiment.

FIG. 2 is a circuit configuration block diagram of the simulation driving apparatus shown in FIG.

FIG. 3 is a diagram showing simulated space coordinates.

FIG. 4 is a diagram illustrating a background in simulated space coordinates.

FIG. 5 is a graph of an equation of a first-order lag when a smoothing coefficient is set to 20;

FIG. 6 is a graph of an equation of a first-order lag when a smoothing coefficient is set to 5;

FIG. 7 is a flowchart of a common function A.

FIG. 8 is a graph in which points are plotted every tenth on the graph of the first-order lag equation.

FIG. 9 is a graph in which points are plotted every fifth point on the graph of the first-order lag equation.

FIG. 10 is a diagram showing a vehicle passing over a step.

FIG. 11 is an enlarged view of a step portion in FIG. 10;

FIG. 12 is a flowchart showing a smoothing process for the first embodiment.

FIG. 13 is a diagram showing a vehicle passing through polygons having different inclinations in the traveling direction of the vehicle.

FIG. 14 is a diagram showing the inclination of a polygon to which a vehicle moves.

FIG. 15 is a flowchart illustrating a smoothing process according to the second embodiment.

FIG. 16 is a diagram showing a vehicle passing through a polygon having a different inclination in the vertical direction of the traveling direction of the vehicle.

FIG. 17 is a diagram illustrating the inclination of a polygon to which a vehicle moves.

FIG. 18 is a flowchart illustrating a smoothing process according to the third embodiment.

[Explanation of symbols]

2 ... Simulated driving device 4 ... Simulated vehicle 6 ... Display box 7 ... Own vehicle 12, 16 ... Traveling direction vector 18 ... Vector in the vertical direction of traveling direction 20 ... User 50 ... Steps 60, 62, 66, 68, 70, 72 ... adjacent polygon 64 ... curve

Claims (5)

[Claims] An information processing apparatus comprising: a plurality of polygons that are provided to a user based on input information based on a user operation on an input device, position information of a virtual vehicle in a simulation space, and simulated background information; A simulated driving device including means for displaying a simulated field of view; a smoothing calculating means for obtaining information calculated from a terrain display polygon and first information relating to the virtual vehicle using a first-order lag equation; Means for generating an image of the virtual vehicle from the information obtained by the means. 2. The simulated driving device according to claim 1, wherein the first information includes information on the height of the virtual vehicle in the simulated space. 3. The simulated driving device according to claim 1, wherein the first information includes information on a tilt of the virtual vehicle in a traveling direction in the simulated space. 4. The simulated driving device according to claim 1, wherein the first information is information on a tilt in a direction perpendicular to a traveling direction of the virtual vehicle in the simulated space. A simulated driving device comprising: 5. The simulated driving apparatus according to claim 1, wherein a smoothing number of the first-order lag equation is variable.