JPH09138863A - Three-dimensional motion generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically decide the balance of a posture by efficiency modeling the three-dimensional movement of a complicated structure like the human so as to consider effect of gravity. SOLUTION: A skelton structure defining part 2 concretely defines the complicated skelton structure such as the human, etc., by inputting a hierarchical relation, the degree of freedom of joints and a parameter for dynamical analyzing. When the locus of the tip part of a foot is given, a skelton position specifying part 1 and a posture control part 3 decides the posture of the position of a foot part. When angular information of each joint of the foot is given, a dynamical analytic part 4 analyzes the dynamics of the foot part through the use of the analytic parameter of the linkage of the foot to generate a force and torque information on each joint of the foot. Then a balance arithmetic part 5 calculates the balance of a structure through the use of Newtonian formula. Thus a three-dimensional motion generator automatically decides the posture of an upper half of the human body when the posture of the lower half of the body is set.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a natural motion of a structure having a complicated skeletal structure such as a human being in the field of image production such as CF and movies using computer graphics (CG). The present invention relates to a three-dimensional motion generation device that generates or analyzes a posture change.

[0002]

2. Description of the Related Art TV commercials and game console software have been attracting attention as fields of use of CG. In the conventional CG, efforts have been made to create a high-quality still image over time due to restrictions due to calculation or production time. However, as hardware and software technologies have improved over the last few years, CG animation has been emphasized especially in the game market.

In these fields, quick movement or natural movement is required for appearing persons or animals. T
In the field of V and movie animation generation, an interpolation method called a key frame method has conventionally dominated, and this method is basically used also in the above-mentioned CG animation production.

The key frame method will be briefly described below. First, the movement of a character such as a human, an animal, or a robot that appears in a key frame at a time t0 of interest is modeled for an image that changes in the time axis direction.
Similarly, a time t1 (>) when a certain time has elapsed from the key frame
Create and save the same character movement at t0).
In this way, the required images are set in the number of key frames required in the time axis direction. When actually reproducing the animation, the above-mentioned plurality of key frames, that is, the time t
By interpolating the motion of each character at 0, t1, ... By using, for example, a joint position or the like using a linear or spline function, the motion in a missing frame between key frames is compensated. In this way, a continuous animation is produced.

Generally, the movement of a CG character includes a global movement that represents a locus of rearrangement and movement of the character in a three-dimensional space, and a local movement that is not related to the arrangement, such as a walking movement or a movement. Among these, the former can set the reference position of each character at a key time in the three-dimensional space by the above-mentioned key frame method, and then interpolate between them to easily specify the movement. .
However, for example, when swinging an arm in a golf swing,
It is difficult to set local movements in the skeletal structure such as foot movements during walking movements easily and naturally by only the key frame method.

On the other hand, in recent years, when modeling a local motion of a character having a complicated skeletal structure such as a human, a method called motion capture is being used. This defines movement by attaching markers to the main parts of the human body (tens of points such as joints and heads) as a model, and making the model perform the necessary movement. Furthermore, it is a method of using a detector such as a camera or a sensor to measure the movement of a human main part at a certain time interval using three-dimensional coordinates, and using that data to model a local movement.

Optical and magnetic sensors have been developed depending on the types of sensors. The motion of the main part of the human captured by the motion capture is reproduced as the motion on the computer by using the forward kinematics method based on the skeletal structure. The kinematics method is a technology developed mainly in robotics. In a skeleton model with a linear link structure composed of links and joints, the joint angle (maximum 3 degrees of freedom) and position (maximum 3 degrees of freedom) By setting, the posture of the skeleton model is determined. By applying this kinematics method to a character having a skeletal structure created by CG, it is becoming possible to reproduce a complicated skeletal structure of a human or the like by natural movement.

[0008]

However, in the conventional human motion control using the kinematics method, the position of the center of gravity of a human having a skeletal structure, the direction vector at the reference point, and the like have not been taken into consideration. In addition, the balance of the upper half of the body when moving both legs, such as when walking upright with two legs, was ignored. Therefore, even if one leg of a human standing upright on the ground is lifted using the inverse kinematics method, the posture of the upper half of the body does not change, and the posture is unnatural compared to the actual movement of a human. It was.
Further, there is a problem in that when the posture of the upper half of the body is determined by using the kinematics method, the posture greatly depends on the skill of the operating operator.

The present invention has been made in view of such conventional problems, and efficiently models a three-dimensional motion in a complicated structure such as a human and considers the influence of gravity. Thus, it is an object of the present invention to realize a three-dimensional motion generation device that automatically determines the balance of postures.

[0010]

In order to solve this problem, in the three-dimensional motion generating apparatus of the present invention, the skeleton structure defining unit defines a skeleton structure called a skeleton to define a complicated structure such as a human. Then, the skeletal structure is assigned to the given character. Moreover, the dynamics (dynamics) is calculated by assigning a volume including each part of the skeletal structure. When the trajectory of a part of the skeleton structure in the three-dimensional space is given, the posture control unit determines the posture of the skeleton structure using kinematics. Further, the balance calculation unit defines the gravity acting on the reference position of the skeletal structure, and calculates the balance at the reference position when a plurality of postures or movements of the feet supporting the structure are given.

Thus, when modeling the postures and movements of the arms and legs of a character having a complicated structure, the concept of balance is considered by considering the gravity acting on the reference position (root of the skeletal structure). Can be adopted.
Furthermore, for example, when modeling walking movements,
When multiple postures that support gravity are given, the posture of the whole body can be determined easily and naturally by calculating the moment of force centered on the reference position based on the postures and movements of the legs. it can.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 defines a skeleton structure defining section for defining a skeleton structure by the lengths of joints and links, and their three-dimensional positions and connection relationships, and the skeleton structure defining section. For each joint of the skeletal structure described above, a skeletal position designating unit that gives a rotational angle of the joint or a three-dimensional coordinate position of the joint in time series according to the degree of freedom of rotation and the degree of freedom at any time, and the skeletal structure definition From the skeleton structure given by the section and the angle information of the arbitrary joint given by the skeleton position specifying section, the posture control section for obtaining the position of the joint at any time based on inverse kinematics, and the skeletal structure defining section For each link of the joint at any defined time, set the center of mass and volume, calculate the dynamic characteristics of each link, and then calculate the torque characteristics of each joint obtained from the dynamic characteristics calculation of the skeletal structure. A dynamic analysis unit that changes based on the evaluation function of energy minimization or work minimization of the skeletal structure, and based on the changed torque characteristics of each joint, converts it into a joint angle using forward dynamics calculation. And are provided.

With such a structure, the dynamic analysis unit sets the center of mass and volume for each link of the joint at any time defined by the skeleton structure definition unit, and calculates the dynamic characteristics of each link. To do. Furthermore, the torque characteristics of each joint obtained from the calculation of the dynamic characteristics of the skeletal structure are changed based on the evaluation function of energy minimization or work minimization of the skeletal structure, and the torque characteristics of each joint after the change are changed. Then, the joint angle is converted using forward dynamics calculation.

According to a second aspect of the present invention, a skeleton structure defining section for defining a skeleton structure of a character by the lengths of joints and links, and their three-dimensional positions and connection relationships, and the skeleton structure defining section are defined. For each joint of the skeletal structure, a skeletal position specifying unit that gives a rotational angle of the joint or a three-dimensional coordinate position of the joint in time series according to the degree of freedom of rotation and the degree of freedom at any time, and the skeletal structure defining unit. Defined by the skeletal structure definition unit and a posture control unit that determines the position of the joint at an arbitrary time based on the inverse kinematics from the given skeletal structure and the angle information of the arbitrary joint given by the skeleton position designation unit. When the trajectory of an arbitrary joint included in a plurality of legs supporting the weight of the skeletal structure is given to each link of the joint, the posture control unit calculates the posture of the foot based on inverse kinematics. Furthermore, based on the dynamics calculation using the results, a dynamics analysis unit that calculates the torque acting on the bases of the legs of the skeletal structure, a straight line including the root position and the bases of the legs that is the reference of the skeletal structure, or It is characterized by further comprising: a balance calculation unit that determines balance equations of force and moment with respect to a plane and solves the relational equations to determine the posture of the upper half of the skeleton structure.

With such a configuration, the dynamic analysis unit gives a trajectory of an arbitrary joint included in a plurality of legs supporting the weight of the skeletal structure to each link of the joint defined by the skeletal structure defining unit. In this case, the posture control unit calculates the posture of the foot based on the inverse kinematics. Further, based on the dynamics calculation using the results, the torques acting on the bases of the legs of the skeletal structure are calculated. The balance calculation unit finds balance equations of force and moment with respect to a straight line or a plane including the root position of the skeleton structure and the roots of a plurality of feet, and solves the relational expression to determine the upper body of the skeleton structure. Determine your posture.

According to a third aspect of the present invention, a skeleton structure defining section that defines a skeleton structure of a character by the lengths of joints and links, and their three-dimensional positions and connection relationships, and the skeleton structure defining section are defined. For each joint of the skeletal structure, a skeletal position specifying unit that gives a rotational angle of the joint or a three-dimensional coordinate position of the joint in time series according to the degree of freedom of rotation and the degree of freedom at any time, and the skeletal structure defining unit. Defined by the skeletal structure definition unit and a posture control unit that determines the position of the joint at an arbitrary time based on the inverse kinematics from the given skeletal structure and the angle information of the arbitrary joint given by the skeleton position designation unit. When a plurality of legs and hands that support the weight of the skeletal structure and joint loci included in the neck are given to each link of the joints, the legs and hands are calculated based on the inverse kinematics in the posture control unit. , The posture of the body is calculated, and based on the calculated dynamics, the dynamics analysis unit that calculates the forces and torques that act on the bases of the legs, hands, and neck of the skeletal structure, and the body reference The position of the upper body of the entire skeletal structure is determined by finding the equilibrium equations of force and moment for the plane including the root position and the bases of the feet and the hands and neck, and solving the relational expressions. And a balance calculation unit for performing the same.

With such a configuration, the dynamic analysis unit determines, for each link of the joint defined by the skeletal structure defining unit, the trajectory of the joints included in a plurality of feet, hands and necks that support the weight of the skeletal structure. When given, the postures of the foot, hand, and neck are calculated based on the inverse kinematics in the posture control unit. Furthermore, based on the dynamics calculation using the results, the forces and torques acting on the bases of the feet, hands and neck of the skeletal structure are calculated. The balance calculation unit finds the equilibrium equations of force and moment on the plane including the root position of the body and the roots of the feet, hands and neck, and solves the relational expressions to solve the entire skeletal structure. Determine the upper body posture.

A three-dimensional motion generation apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the basic configuration of a three-dimensional motion generation device according to this embodiment. 2 is an explanatory view showing a human skeleton structure, FIG. 3 is a view showing a link structure for dynamic analysis, and FIG. 4 is a view showing a basic human lower body skeleton structure.
FIG. 5 is a diagram showing the balance of forces and moments of the lower body of a human, and FIG. 6 is an explanatory diagram of the balance of forces and moments of the whole human body. In FIG. 1, the three-dimensional motion generation device includes a skeleton position designation unit 1, a skeleton structure definition unit 2, a posture control unit 3, a dynamics analysis unit 4, and a balance calculation unit 5.

The operation of the three-dimensional motion generating apparatus thus constructed will be described with reference to FIGS. First, in the skeleton position designation unit 1, as shown in FIG. 2, a complex structure such as a human is defined by a joint structure called a skeleton, and three-dimensional coordinate positions of the joint (also called a joint) or angle information (direction) of the joint. ) Is given as time series data. The data includes the name of the link (Segment), the number of frames, the frame rate (30 frames per second in the example), and the position of the joint (Xtran, Ytra).
n, Ztran), angle (Xrot, Yrot, Zro
t) and scale (Xscale, Yscale, Zsc
ale). These data are given as a time series by the number of frames. In general, using a motion capture system, etc., the main joint positions of the model human,
For example, it is also possible to attach a magnetic or optical marker to an elbow, a wrist, or the like and move the marker to obtain the above-mentioned data from locus information in the three-dimensional space of the marker position.

Next, the skeleton structure defining unit 2 defines a skeleton structure of a character such as a human. FIG. 2B is a model diagram of a standard human skeleton structure. FIG.
The portions indicated by black circles in (a) and (b) are portions corresponding to joints, and straight lines connecting the joints are called links. The skeleton structure of FIG. 2 requires the root as a reference position, the parent-child relationship of each link, the positional relationship of each joint, the degree of freedom of rotation with a maximum of three degrees of freedom, and the limitation of the rotation angle. The skeleton structure definition unit 2 expresses the structure of the skeleton to be analyzed from now on by the hierarchical relationship and the initial value (link length) as shown in FIG. 2, and holds it in the internal memory. The posture control unit 3 uses the data structure for analysis defined by the skeleton structure definition unit 2 to analyze the posture of the skeleton using kinematics.

Next, a basic posture analysis method will be described. Posture analysis applies the method that has been used for posture control of robot arms. In the open-loop linear link structure represented by joints and links as shown in FIG. 2A, the joint that is the reference of analysis is called a root, and the origin of the coordinate system for analysis is made to coincide with the root. The coordinate system will be referred to as the right-handed system hereinafter. The end point of analysis is called an effector, and is generally the tip of the arm.

The information necessary for attitude control is the parent-child relationship of links, the initial position of the skeleton structure, the maximum three degrees of freedom of rotation of each joint, and the limitation of the rotation angle of each joint. For a certain skeleton structure, a method of obtaining angle information of each joint is called inverse kinematics when a total of 6 elements, that is, 3 elements for translation and 3 elements for rotation, are given as the temporal change of the trajectory of the effector part. . On the contrary, the method of obtaining the position of the effector when a slight time change of the angle of each joint is given is called forward kinematics. For details of kinematics, refer to 1) "Robot Engineering" by Hirose (Sokabo), 2) "Mechanics and Control of Robots" by Arimoto (Asakura Shoten) as references. ing.

Generally, there is a linear relationship between the angle information θi (t) of each joint of the skeleton structure shown in FIG. 2, more precisely, the minute time change amount and the minute change amount of the maximum 6 variables of the effector posture. , Its proportional coefficient matrix is called the Jacobian matrix, and the inverse relationship is called the inverse Jacobian matrix. In the forward kinematics, the Jacobian matrix is determined by sequentially obtaining the link length and the rotation matrix of each joint from the skeleton structure shown in FIG. 2 in the posture control unit 3 of FIG.
Furthermore, by providing the time-series data of the angle change of each joint from the skeleton position designation unit 1, the position of the effector at a certain time can be uniquely determined using the Jacobian matrix.

On the other hand, in inverse kinematics, the inverse Jacobian matrix is calculated mathematically, for example, by the "bare-out method", and the three-dimensional coordinates of the effector given by the skeleton position designating unit 1 are applied to it, so that each time The position of any joint in can be determined.

In the dynamic analysis unit 4 of FIG. 1, an elliptic cylinder for analysis as shown in FIG. 3 is considered as each link of the skeleton structure shown in FIG. However, a cylinder may be used for ease of calculation. For the dynamic analysis, the inertia tensor of the cylindrical shape, the position of the center of gravity, the mass, etc. are required. Therefore, using the link for analysis, first calculate the inertia tensor of the link. As the origin of the calculation, the coordinate system is set at the position of the joint near the root with respect to the link. Further, the sum of the kinetic energy and potential energy of each link structure is calculated as a Lagrangian, and this Lagrangian is differentiated with respect to time to calculate the torque acting on each joint of the skeleton structure shown in FIG. In addition to this, the force acting on each joint is calculated by establishing a relational expression of force balance and moment with respect to the orthogonal coordinate system of the skeleton structure shown in FIG.
It can also be obtained by the Ewton-Euler method. For details, see Hirose's "Robot Engineering" (Sokabo).

As described above, the dynamics analysis unit 4 calculates the force and torque of each joint portion associated with the movement from the trajectory of the skeleton in the three-dimensional space given by the skeleton position designation unit 1. For example, by applying the above-described dynamics calculation to time data such as a golf swing of a human obtained by motion capture or the like, the torque characteristic acting on an arbitrary joint in a certain swing can be calculated. Further, it is also possible to change the calculated torque characteristic of each joint based on the evaluation function of energy minimization or work minimization, and convert it into a joint angle with forward dynamics. The work here is the product of the torque value of each joint of the skeletal structure to be calculated and the minute change amount of the joint angle, and is the sum of all joints. In the energy minimization, the sum of squares of the minute changes in the angles of the joints is used as the evaluation function.

As described above, (1) the posture of a joint structure is determined by using inverse kinematics. (2) The torque characteristic is calculated from the motion using inverse dynamics.
(3) The torque characteristic is changed based on the above evaluation function. (4) The posture control unit 3 and the dynamics analysis unit 4 calculate a sequence for converting the torque characteristics into angle data of each joint by the forward dynamics method. That is, in the portion surrounded by the dotted line in FIG. 1, it becomes possible to correct the motion considering the dynamics with respect to the given trajectory.

Next, with respect to the motion or posture of the skeleton structure obtained as described above, how to determine the posture (balance) of the whole body in consideration of the influence of gravity will be described.
The balance calculation unit 5 in FIG. 1 determines this posture. Generally, in the conventional kinematics method described above, a joint serving as a root is used as a reference, and a posture such as a limb is determined by a relative position from the joint.

First, the conventional inverse kinematics will be described with reference to FIG. 4 as an example. FIG. 4A shows the initial state in the lower half of the human skeleton structure. Assuming that the posture of the joint is the angle of the joint at a certain time, in the inverse kinematics method, when the trajectory of the left toe in the three-dimensional space is given as shown in FIG. 4B, the left ankle, the left knee,
It is possible to determine the posture of each joint of the left foot joint. In this case, the reference position for the kinematics calculation of the left foot or the right foot, that is, the root position is the base of the foot indicated by a double circle in the figure. Therefore, even if the locus of the tip portion of the left foot is determined as shown in FIG. 4B, the posture of the reference position does not change.

Qualitatively, this means that conventional kinematics alone has no effect on the posture of the upper body or hands even if one leg is lifted and its position is determined in the human skeleton model. To do. In order to avoid such a result temporarily, it is possible to specify the calculation range of kinematics across routes. However, even with this method, it requires a great deal of skill to define the calculation range from one foot of the human to the tips of both hands and the tip of the head, and to determine the natural posture of the entire human body. To do.

In order to easily avoid these drawbacks, a method of determining a posture in consideration of gravity and torque acting on each part of the skeleton and their balance will be described below. Here, a structure that walks on two legs like a human will be described as an example, but the same applies to a structure that moves with more legs. FIG. 5: is explanatory drawing which shows the force which acts on both legs of a human, and its balance. This figure shows an equilibrium state in which the upper half of the body generally tilts to the right when the locus of the human left foot of FIG. 4 is given. Further, relational expressions quantitatively showing this balance relation are equations (1) to (3).

(Equation 1)

In equations (1) to (3), XY is used for simplicity.
Considering only the movement in a two-dimensional plane such as a plane, Z
The formula can be extended in exactly the same way even when an axial movement is entered. Among these equations, the equations (1) and (2) are called Newton's equations, and are equations of motion showing the balance relationship between the forces in the X direction and the Y direction, respectively. Where m is the mass of the entire skeleton, f1 and f2 are the forces acting on each foot, τ is the torque (rotational moment) at the base of both feet, l1 is the length of the left foot, l2 is the length of the right foot, and d is the position of the center of gravity. Shows the distance from (double circle) to both feet. Further, θ1 is an angle formed with the reference line of the left foot, and θ2 is an angle formed with the reference line of the right foot. Further, φ is the inclination of the hipbone with respect to the horizontal direction.

Further, the expression (3) is called the Euler's expression, and is an expression showing the balance of moments generated by the rotation at the joint part of the skeleton. Here, I represents the center of gravity of the body part, for example, the inertia tensor at the center of gravity in FIG. Also, the dash symbol on the upper right of the character is a differential operation in time.

With respect to the human skeleton model shown in FIG. 4A, when the locus of the right foot is given, for example, the torque τ and the force f acting on the base of the right foot are calculated by the dynamic analysis unit 4 of FIG. Ask. By calculating the balance equation at a certain time from these values, θ and φ can be obtained. That is, the posture direction P of the human skeletal structure can be uniquely determined.

In the above example, only the lower half of the human body is shown for the sake of simplification of the description, but as shown in FIG. 6, the balance including both hands and the neck is within the plane surrounded by the one-dot chain line (1). It is possible to determine the direction of the whole body when the postures of the hands and feet are given by establishing a relational expression similar to (3). In that case, the balance problem in the three-dimensional space that also considers the component in the Z-axis direction can be obtained by similarly expanding (1) to (3).

As described above, in the three-dimensional motion generation apparatus of this embodiment, as shown in FIG. 7, the skeleton structure defining unit 2 defines a complicated skeleton structure such as a human being in step S1 as shown in FIG. . At this time, the hierarchical relation, the degree of freedom of the joint, and the parameters for the dynamic analysis are input. In the next step S2, the skeleton position specifying unit 1 and the posture control unit 3 determine the posture of the foot portion when the trajectory of the tip of the foot is given. As a result, the angle information of each joint of the foot is output. In step S3, when the angle information of each joint of the foot is given, the dynamic analysis unit 4 analyzes the dynamics of the foot using the analysis parameters of the link of the foot. Then, the force and torque information of each joint of the foot is generated. In step S4, the balance calculation unit 5 causes the Newt
Balance calculation is performed using the on-Euler formula. By setting the posture of the lower body in this way, the posture of the upper body of a human being is automatically determined. In this embodiment, a human having a complicated skeletal structure has been described, but a character other than a human may be used.

[0037]

As described above, according to the present invention, when three-dimensional motion data of a complicated structure such as an arm or a foot of a character such as a human being is created, its skeletal structure is defined and one of the structures is defined. When a trajectory of a part, such as a hand or a foot, is given, the torque or force acting on the limb is calculated by dynamic analysis, and based on the result, the equilibrium relationship between the force and the moment at the standard for supporting the weight is calculated. By the calculation, it is possible to easily and naturally determine the posture when the character stands upright and the legs are raised, or the posture when climbing stairs.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic configuration of a three-dimensional motion generation device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an example of a human skeleton structure.

FIG. 3 is a diagram showing a link structure for dynamic analysis.

FIG. 4 is an explanatory diagram showing the basic skeletal structure of the lower half of the human body.

FIG. 5 is an explanatory diagram showing a basic balance between a lower body force and a moment.

FIG. 6 is an explanatory diagram showing a basic equilibrium between forces and moments of a whole human body.

FIG. 7 is an explanatory diagram showing signal processing of the three-dimensional motion generation device of this embodiment.

[Explanation of symbols]

 1 Skeleton position designation unit 2 Skeleton structure definition unit 3 Posture control unit 4 Dynamics analysis unit 5 Balance calculation unit

Claims (3)

[Claims] 1. A skeletal structure defining unit that defines a skeletal structure by the lengths of joints and links, and their three-dimensional positions and connection relationships, and for each joint of the skeletal structure defined by the skeletal structure defining unit, A skeleton position specifying unit that gives a rotation angle of the joint or a three-dimensional coordinate position of the joint in time series according to the degree of freedom of rotation and the degree of freedom at an arbitrary time, a skeleton structure given by the skeleton structure defining unit, and the skeleton From the angle information of the arbitrary joint given by the position designation part,
A posture control unit that determines the position of a joint at an arbitrary time based on inverse kinematics, and links for each link of the joint at an arbitrary time defined by the skeletal structure defining unit by setting the center of mass and volume The dynamic characteristics of each joint were calculated, and the torque characteristics of each joint obtained from the calculation of the dynamic characteristics of the skeletal structure were changed based on the evaluation function of energy minimization or work minimization of the skeletal structure. A three-dimensional motion generation apparatus comprising: a dynamics analysis unit that converts a joint angle based on a torque characteristic of each joint afterwards using forward dynamics calculation. 2. A skeletal structure defining section that defines a skeleton structure of a character by the lengths of joints and links, and their three-dimensional positions and connection relationships, and each joint of the skeletal structure defined by the skeleton structure defining section. On the other hand, a skeleton position designation unit that gives a rotation angle of the joint or a three-dimensional coordinate position of the joint in time series according to the degree of freedom of rotation and the degree of freedom at any time, and a skeleton structure given by the skeleton structure definition unit, and From the angle information of any joint given by the skeleton position designation unit,
A posture control unit that determines the position of a joint at an arbitrary time based on inverse kinematics, and, for each link of the joint defined by the skeletal structure definition unit, included in a plurality of legs that support the weight of the skeletal structure When the trajectory of the joint is given, the posture control unit calculates the posture of the foot based on the inverse kinematics, and further, based on the dynamics calculation using the result, at the bases of the plurality of legs of the skeletal structure. The dynamics analysis unit that calculates the working torque, and the equilibrium equations of force and moment are calculated for the straight line or plane that includes the root position that is the reference of the skeletal structure and the roots of multiple legs, and the relational equation is solved. A three-dimensional motion generation device comprising: a balance calculation unit that determines the posture of the upper half of the skeleton structure. 3. A skeletal structure defining unit that defines a skeleton structure of a character by the lengths of joints and links, and their three-dimensional positions and connection relationships, and each joint of the skeletal structure defined by the skeleton structure defining unit. On the other hand, a skeleton position designation unit that gives a rotation angle of the joint or a three-dimensional coordinate position of the joint in time series according to the degree of freedom of rotation and the degree of freedom at any time, and a skeleton structure given by the skeleton structure definition unit, and From the angle information of any joint given by the skeleton position designation unit,
A posture control unit that determines the position of a joint at an arbitrary time based on inverse kinematics, and a plurality of feet, hands, and necks that support the weight of the skeletal structure for each link of the joint defined by the skeletal structure defining unit. When the trajectory of the joint included in is given, the postures of the feet, hands, and neck are calculated based on the inverse kinematics in the posture control unit, and the skeleton is calculated based on the dynamics calculation using the result. A dynamics analysis unit that calculates the force and torque acting on the bases of the feet and hands and the base of the neck of the structure, the reference root position of the body, and the plane including the bases of the feet and the hands and the base of the neck. A three-dimensional motion generating device, which comprises: a balance calculation unit that determines a balance equation of force and moment and solves the relational expression to determine the posture of the upper half of the entire skeleton structure. .