JPH09237351A - Processing method for generating walking operation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain a numerized walking operation model considering also right and left asymmetricity by synthesizing a method for generating straight walking operation from a certain position to another position on a straight line and a method for generating rotating operation around a certain axis. SOLUTION: An initial/final condition calculating means calculates an initial condition and a final condition such as a position on a human body model and a joint angle so that foot parts can be landed on walking points set on a curved route. When a supporting foot is put on a point A and a free foot is moved from P to B in the case of turning a direction from the point A to a the point B, a straight walking operation generating means moves the free foot to a point B' separated from the point A by a distance equal to a segment AB and having the same walking direction, a rotational operation generating means generates rotation so that the free foot arrives at the point B during the generation of walking operation to the point B' by the straight walking operation generating means and an operation synthesizing means synthesizes both the operation. Consequently forward walking operation fixing the supporting foot on the point A and moving the free foot from the point P to the point B while turning its direction is generated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a walking motion generation processing method for creating an animation by computer graphics using a computer, for example, and for simulating walking of a human figure in a room such as CAD. Is.

[0002]

2. Description of the Related Art Modeling the human body as an articulated structure,
When a walking motion of a human figure is generated using a computer or the like, most of the straight walking motions are mathematical expressions only within the vertical plane.

[0003]

A curved path (including a straight path) by automatically generating a turn to the left or right.
There is a problem that it is difficult to automatically generate walking motions along the line.

According to the present invention, a human body is represented as a multi-joint structure composed of a rigid body and mass points, and when a walking motion of a human figure on a curved path is automatically generated, the direction is automatically changed to the left or right. In order to realize it, the purpose is to realize a mathematical model of walking motion that also considers left-right asymmetry.

[0005]

SUMMARY OF THE INVENTION The present invention separates a model for walking motion into a straight-ahead moving motion part from one point to another and a rotary motion part rotating about a vertical axis, each of which is independent. Then, after the calculation, both actions are combined.

In addition, the model for the rotary motion part is
A body model that is an object that rotates around a rotation axis
And the time t when one foot lands_APeople in
The direction in the horizontal plane that the front of the body model faces, and the subsequent landing
Time t when another foot to land _BBefore the human body model in
When the angle between the plane and the direction in the horizontal plane is α
And the walking time t of one step_step(= T_B-T_A) Passes
Rotate the human body model by the rotation angle α required for time.
Let

Furthermore, when the physical law is used for rotation, the equation of motion of rotation is applied to the human body model, and the rotation angle required at the time when the walking time t _step (= t _B −t _A ) of one step elapses. Rotation torque is applied to rotate the human body model by α.

The present invention has an initial / end condition calculating means and a walking motion generating means. Hereinafter, a one-step walking motion (from landing of one foot to landing of another foot) is referred to as “step”, and the time required for the step, that is, the landing time t _{A of} one foot from the landing time t _{A of} another foot to be landed subsequently.
_The time required to reach _B is t _step . In addition, the direction in the horizontal plane where the front surface of the human body model faces at time t _A

[0009]

[Equation 1]

And the direction in the horizontal plane at which the front surface of the human body model faces at time t _B

[0011]

[Equation 2]

Let α be the angle formed by and t (t _A ≤t
Direction in the horizontal plane where the front surface of the human body model faces ≦ t _B ).

[0013]

(Equation 3)

[0014]

[0015]

(Equation 4)

The angle between and is represented by the total rotation angle Θ (t).
Constraint condition μ for each component of parameters F (t) and F (t) necessary for displaying the structure of the human body model, straight forward motion
(F (t)) = 0, the constraint condition ν (G for each component of the parameters G (t) and G (t) necessary for displaying the rotational movement
It is assumed that (t)) = 0 is known, and the line segment approximation of the curved path, the duration of each step, and the like have been preprocessed.

[0017] Figure 1 is an example of a curved path and the line segment approximated gait point (horizontal view), Note that _{S 0 → S 1 → S 2} → S 3 ... order, shall land on the right and left alternately, alpha _i is Line segment S _i-1 S
_The angle between _i and the line segment S _i S _{i + 1} is shown. Fig. 2 is an exploded view of the step, and there is a supporting leg at point A, and the free leg is P → B.
, And α is the direction

[0018]

(Equation 5)

And direction

[0020]

(Equation 6)

It represents the angle between and. FIG. 3 shows a block diagram of the present invention and a processing flow. A. Initial / Terminal Condition Calculation Means 1 In the initial / terminal condition calculation means 1, as shown in FIG. 1, the position of the human body model and the position of the human body model are set so that the foot can be landed on a walking point set on a given curved path. Compute initial and final conditions such as joint angles.

At this time, it is assumed that the walking motion is composed of a straight-ahead driving motion and a rotating motion, and a constraint condition for the straight-ahead driving motion and a constraint condition for the rotating motion are calculated respectively. However, the constraint condition for the rotation operation is calculated from the diagram in which the curved path is projected on the horizontal plane as shown in FIG.

Although the landing point is approximated by the point S _i in FIG. 1, the constraint condition may be calculated by appropriately adjusting it according to the distance between the left and right legs of the human body model. The same applies to the following processing.

B. Walking motion generating means 2 It should be noted that the order of straight-ahead movement motion generation and rotation motion generation may be either first, or both may be executed in parallel.

The walking motion generating means 2 is composed of a straight-ahead movement motion generating means 3, a rotating motion generating means 4 and a motion synthesizing means 5. That is, as shown in FIG. 2, for example, in the case of a step of changing the direction from point A to point B, if the supporting foot is at point A and the free leg moves from P to B, it is as if point A From the straight line movement AB to the point B ′ that is equidistant from the line segment AB and the walking direction does not change, and while the straight line movement generation unit 3 generates the walking movement to the point B ′. Then, by synthesizing the motion of both of the rotation motion generating means 4 that causes the free leg to reach the point B, the supporting foot is at the point A, and the free leg moves from P to B. It may be considered to be composed of the motion synthesizing means 5 for generating the forward walking motion while performing the above.

With respect to the straight-ahead movement motion generating means 3, a stepping motion from one given foot landing point A to the next foot landing point B'is generated, and at time t (t _A ≤t≤t _B ). Any method can be used as long as it generates time-series data F (t) such as a joint angle and a position. Further, even when the terrain changes in the vertical direction, the straight ahead movement generation means 3
The method does not matter. For example, reference [1] (Ken Kouguchi, “Walking motion generation processing method”, JP-A-6-251122) or Document [2] (Cylinder mouth
Ken, Sakaino Hidetomo, Watanabe Yasuko, "Human Walking Animation Using Terrain Adaptive Walking Motion Generation Method", Theological Theory
D-II, Vol.J77, No.8, pp.1663-1670, 1994.) may be used.

The rotating motion generating means 4 rotates the human body model around the point A or a point in the vicinity thereof when the straight traveling motion generating means 3 generates the straight traveling motion from the point A to the point B ′. Produces an effect of moving to point B instead of point B '. In the case of straight walking that does not require rotation, the rotation motion generation means 4 may be skipped.

Rotation calculated by the constraint condition calculation means
If the angle is given by α, the time t _stepJust α rotation
Vertically from the center point of the landing foot so that the angle can be obtained
Rotate the human body model around the axis of rotation that is oriented.
Even if this rotation axis tilts or moves during rotation,
Included in the means. In addition, even if the rotating shaft itself moves, this means
Included.

Another method of generating a rotary motion is to generate a time t (t _A
The function for generating the rotation angle Θ (t) in ≦ t ≦ t _B ) is such that Θ (t) = g (t), g (t _A ) = 0, g (t _B ) = α, Using g (t), time t (t _A ≦ t ≦ t
Time series data G such as joint angle and position in _B )
Any object can be used as long as it can generate (t). For example, even if it rotates at a constant angular velocity, when applying the physical law to the generation of a motion that changes the direction to the left or right, the human body is composed of a mass and a rigid body. Approximately with a joint structure, set up a motion equation for left and right rotation with the joint angle as a variable, and apply force so that it matches the left and right direction change angle. It may be generated.

In the case of establishing the equation of motion in the rotation generation means, the equation of motion when the moment of inertia of the human body model around the axis of rotation is I (t) and the torque of rotation is T (t) is given.

[0031]

(Equation 7)

The rotational motion is generated by calculating T (t) so that Θ (t _B ) = α is satisfied.
The motion synthesizing means 5 is time-series data F of the position and joint angle of the human body model generated by the straight ahead movement motion generating means 3.
(T) and the time-series data G (t) of the position and joint angle of the human body model generated by the rotational motion generating means 4 are combined to newly generate the time-series data H (of the position and joint angle of the human body model. Calculate t) and generate a walking motion for a given curved path. Any combination of F (t) and G (t) may be used as long as it satisfies the constraint condition at the time t _A and the time t _B. For example, H (t) = h (F (t), G ( t)), t _A ≦ t ≦ t _B (2)

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment] FIG. 4 shows a first embodiment of the present invention (first embodiment).
It is. Further, FIG. 5 shows a human body model and a rotation model in the first embodiment.

Step S1 Let us assume that the human body model is approximated by a multi-joint structure composed of rigid rods as shown in FIG. In step S2, the time required for one step is t _step , and the present invention finally determines the time series data H of the joint angle for each Δt.
Let (t _i ), (i = 0, 1, 2, ..., N) be generated. However, N = t _step / Δt, t ₀ = t _A , t _N
= T _B, and Δt is, for example, the time required for redrawing in computer graphics.

Step S3 For example, a walking motion from the point P to the point B'is generated by the walking motion generated by the straight-ahead driving motion generation means 3 realized by the documents [1] and [2], and the joint of the human body model is generated. It is assumed that time-series data F (t _i ) such as angle and position (i = 0, 1, 2, ..., N) has been generated.

After step S4, or at the same time,
Time-series data G such as the joint angle and the position with respect to the rotational movement at each time t _i (i = 0, 1, 2, ..., N)
Calculate (t _i ) (i = 0, 1, 2, ..., N).

G (t _i ) is M rotation angles θ _j (t),
(J = 1, 2, ..., M), G (t) = (θ ₁ (t), θ ₂ (t), ..., θ _M (t)), (3) In this case, the total rotation angle Θ (t)

[0038]

(Equation 8)

The total rotation angle Θ (t) is represented by Θ (t) = g (t, α), g (t₀, Α) = 0, g (t_N, Α) = α, expressed by a function g (t, α) such that (5), and then
Equation (4) and (θ₁(T), θ_Two(T), ..., θ
_M(T)) constraint condition ν (θ₁(T), θ
_Two(T), ..., θ_M(T)) = 0, the rotation motion parameter
Meter G (t_i) = (Θ₁(T _i), Θ_Two(T_i),
…, Θ_M(T_i)) (I = 0, 1, 2, ..., N)
You.

For example, G (t _i ) is a rotation angle θ ₁ (t) about a rotation axis that is vertically upward from the landing foot (A) shown in FIG. 5, and vertically upward from the waist portion (H). And the rotation angle θ ₂ (t) about the rotation axis of G, and G (t _i ) = (θ ₁ (t _i ), θ ₂ (t _i )), i = 0,1,2, ..., N , (6), etc.,

[0041]

[Equation 9]

When the constraint condition for (θ ₁ (t), θ ₂ (t)) is expressed as θ ₁ (t) = θ ₂ (t), (8), etc., equation (7), The parameters (θ ₁ (t _i ), θ ₂ (t _i )) can be obtained from the equation (8).

In the case of the present embodiment, the processing is basically the same regardless of which of the left and right feet is the supporting foot and when the foot is turned in either of the left and right directions. Step S5 After that, the time-series data F such as the joint angle and the position of the human body model generated by the straight ahead behavior generating means 3 by the behavior synthesizing means 5
(T _i ), (i = 0, 1, 2, ..., N) and time series data G representing the rotation generated by the rotation motion generation means 4.
(T _i ), (i = 0, 1, 2, ..., N) are combined,
Time series data H (t _i ), (i = 0, 1, 2, ..., N) representing all joint angles and positions of the human figure model are calculated.

Any synthesis method may be used as long as it satisfies the constraint condition at the time t _A and the time t _N. H (t _i ) = h (F (t _i ), G (t _i )), i = 1,2, ..., N, which is represented by (9). For example, when F (t) and G (t) have no dependency, there is a method of simply adding the two.

Although the rotation angle is represented by the left-handed system in this embodiment, it may be represented by the right-handed system. [Second Embodiment] FIG. 6 shows a second embodiment of the present invention (second embodiment).
It is. Further, FIG. 7 shows a human body model and a rotation model in the second embodiment.

In this embodiment, the human body model is approximated as shown in FIG. The flow of processing is almost the same as that of the first embodiment, but only the part of the process (a) (part of step S4) in FIG. 4 is different, and FIG. 6 shows only that part.

In the rotational motion generating means 4, for example, the time-series data G (t _i ) representing rotation has M rotational angles θ.
_j (t), (j = 1, 2, ..., M), and G (t _i ) = (θ ₁ (t _i ), θ ₂ (t _i ), ..., θ _M (t _i )) , I = 0, 1,2, ..., N, (10), etc., in the horizontal plane of the traveling direction at time t _A.

[0048]

(Equation 10)

And in the horizontal plane of the traveling direction at time t

[0050]

[Equation 11]

The total rotation angle Θ (t) formed by and θ _j (j =
1,2, ..., M) as a function

[0052]

(Equation 12)

In such a case, the moment of inertia of the human figure model around the axis of rotation vertically upward from the landing foot at time t is I (t), and the torque is T (t).

[0054]

(Equation 13)

It is represented by. I (t) may be calculated as a constant value I during the duration of the step, or may be calculated every time t _i as a value that changes with time. At that time, T (t) may be, for example, a function reflecting the floor reaction force at the landing foot or may be a constant value, but Θ (t at time t _N by using an iterative method used in ordinary numerical calculation.
_N ) = α.

That is, T (t) = mr (t), (13) is expressed by using a certain shape function r and a real number m, and the processing shown in FIG. 6 is repeated. When the total rotation angle Θ (t) becomes Θ (t _B ) = α at time t _N , the process is terminated and the process proceeds to the next step. When Θ (t _B ) ≠ α, the value of m is changed by Δm. Increase or decrease i = 1
Repeat from

The value of each θ _j (t _i ) (j = 1, 2, ..., M) at the time t _i (i = 0, 1, 2, ..., N) is determined as long as analytical calculation is possible. Formula (11) and constraint condition formulas ν (θ ₁ (t), θ ₂ (t), ..., θ _M (t)), (14). If not possible, θ ₁ (t _i ) = θ ₂ (t
_An approximate calculation such as _i ) = ... = θ _M (t _i ) may be used.

After that, the motion synthesizing means 5 generates time series data F (t _i ), (i = 0, such as joint angles and positions of the human body model generated by the straight ahead movement generating means 3).
1, 2, ..., N) and time series data G (t _i ), (i = 0, representing the rotation generated by the rotation motion generating means 4).
, 1, ..., N), and time-series data H (t _i ), (i = representing all joint angles and positions of the human figure model).
0, 1, 2, ..., N) are calculated.

Any synthesizing method may be used as long as it satisfies the constraint condition at time t _A and time t _N , and H (t _i ) = h (F (t _i ), G (t _i )), i = 1,2, ..., N, (15) For example, when F (t) and G (t) have no dependency, there is a method of simply adding the two.

In this embodiment, the rotation angle is represented by the left-handed system, but it may be represented by the right-handed system.

[0061]

As described above, according to the present invention,
As shown in the first and second embodiments, the introduction of the mathematical model for automatically realizing the direction change to the left and right,
When automatically generating the walking motion of the person image on the curved path, there is an effect that the walking motion on the curved path (including straight line walking) can be automatically generated.

[Brief description of drawings]

FIG. 1 shows an example (horizontal plan view) of a walking point that is approximated to a curved path and a line segment.

FIG. 2 shows a step exploded view (horizontal plan view).

FIG. 3 shows a configuration diagram and a processing flow of the present invention.

FIG. 4 shows a processing flow of the first embodiment.

FIG. 5 shows a human body model and a rotation model according to the first embodiment.

FIG. 6 shows a processing flow of the second embodiment (only processing (a)).

FIG. 7 shows a human body model and a rotation model in the second embodiment.

[Explanation of symbols]

 1 Initial / Terminal Condition Calculation Means 2 Walking Motion Generation Means 3 Rotational Motion Generation Means 4 Motion Synthesis Means 5 Motion Synthesis Means

Claims (3)

[Claims] 1. A walking motion generation processing method for generating a walking motion of a human image using a computer, wherein when a target object walks along a walking point set on a curved path including a straight path, By combining the method of generating a linear walking motion from a point to another point on a straight line and the method of generating a rotational motion around a certain axis, the walking motion of the target object on the curved path is automatically performed. A walking motion generation processing method, which is characterized in that: 2. The method for generating the rotation motion, wherein in the generation of a one-step walking motion of a person image, when a direction change to the left and right is performed, a direction change angle to the left and right within a walking motion time of one step and 2. The walking motion generation processing method according to claim 1, wherein the walking motion generation processing method is a method of automatically generating a direction-changing walking motion to the left and right by changing the joint angles of the person image so as to match. 3. The method of generating the rotation motion, wherein when applying a physical law to the generation of the direction change motion of the human image to the left and right, the human body is approximated by a multi-joint structure composed of a mass point and a rigid body, It is a method to automatically generate a turning motion to the left and right by establishing a motion equation for left and right rotation with an angle as a variable and applying a force so as to match the turning angle to the left and right. The walking motion generation processing method according to claim 1.