JPH08328631A - Method for simulating robot operation and device therefor - Google Patents

Abstract

PURPOSE: To easily judge a factor that an attitude can not be realized by displaying the effect that the location and attitude of an instructed end can not be realized when displacement amount exceeds each indirect operating limit. CONSTITUTION: A robot reverse kinematix calculation part 20 inputs the data of the target location and attitude of a hand via a final location attitude generation part 14 and solves the reverse kinematix for calculating each indirect displacement amount composing a robot based on this inputted data. When any axis exceeds its operating limit although the reverse kinematix solution can be calculated, the final attitude of the robot, etc., is displayed in accordance with the mode set by an operating mode setting part 12. For instance, the effect that an operation can not be performed because the axis exceeding its operating limit exists is displayed on a screen. When the reverse kinematix solution can not be calculated, the effect that (the robot is not capable of reaching in any way, for instance,) is displayed on the screen.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a simulation method and apparatus used for studying the application of a robot to the environment in which it is installed and for studying the optimum operation path of the robot.

[0002]

2. Description of the Related Art Conventionally, the selection of robots and the confirmation of operation paths have been carried out by a simulation device which can be easily selected and confirmed on a desk instead of trial and error by an actual machine in the field. .

This simulation device is preliminarily input with data on the environment of the site, and is optimal for placing an arbitrary robot in this environment and virtually moving the robot to perform a target work. This is to select the type of robot and to create an optimal work route for that robot.

When creating a work route, data relating to the position and orientation of the working end of the robot is input so that it does not interfere with adjacent devices and is the shortest, and based on this input data, the data is displayed on the screen. The robot is moved, and teaching data is created while verifying this movement.

An example of the operation of the conventional simulation apparatus is shown in the flowchart of FIG.

In order to verify the movement of the robot displayed on the screen, the operator first starts by inputting data on the position and orientation of the hand, which is the working end (S1). . The simulation device solves the inverse kinematics for calculating the displacement amount of each joint forming the robot based on the input data (S2). As a result, when the displacement amounts of all the joints are within the movement limits, the robot can move freely, and therefore each joint is moved by the calculated displacement amount and displayed on the screen (S3). S4).

On the other hand, as a result of obtaining the inverse kinematics, there is a solution, but when moving each joint by the displacement amount based on this, one of the joints exceeds the motion limit, in other words, the mechanical limit. If the hand can be set to the specified position and posture by expanding the joint movement limit, the joint that exceeds the movement limit is moved to that limit value and the movement limit is reached. For the joints inside, move the joints by the calculated displacement,
This state is displayed on the screen (S5, S6). further,
When there is no inverse kinematics solution, it is impossible to set the hand at the instructed position and posture, so the robot does not move and displays the posture as it is (S7, S8).

[0008]

However, in such a conventional simulation apparatus, when the solution of the inverse kinematics does not exist, the robot is not moved at all. There is a problem that it is difficult to judge what kind of measures should be taken without fully knowing whether or not the hand cannot be moved to the designated position and posture.

The present invention has been made in view of the above conventional problems, and the working end of the robot is set at a desired position.
An object of the present invention is to provide a method and apparatus for simulating a robot motion that allows easy investigation of the cause when the posture cannot be set.

[0010]

[Means for Solving the Problems] The present invention for achieving the above object is configured as follows.

The first configuration is a method of simulating a robot operation for studying application of the robot to the environment of the installation site and studying the optimal work route, in which the position and orientation of the robot working end are instructed. Calculate the displacement amount for each joint to realize the position and orientation based on the instruction, and if the calculated displacement amount exceeds each indirect motion limit, or if the displacement amount cannot be calculated, It is characterized in that it displays that the position and orientation of the work end thus specified cannot be realized.

The second configuration is a method of simulating a robot operation for studying the application of the robot to the environment of the installation site and studying the optimal work route, in which the position and orientation of the robot working end are instructed. Calculate the displacement amount for each joint to realize the position and posture based on the instruction, and if the calculated displacement amount exceeds each indirect motion limit, move the joint to the motion limit and then Is displayed, and the fact that there is a joint exceeding the motion limit is displayed.

The third configuration is a method of simulating a robot operation for studying application of the robot to the environment of the installation site and studying the optimal work route, in which the position and orientation of the robot working end are instructed. The displacement amount for each joint to realize the position and orientation based on the instruction is calculated, and even if the calculated displacement amount exceeds the indirect motion limit, the motion limit is ignored and the joint is moved. It is characterized in that it is moved to display the state, and also displays that the specified position and orientation of the working end cannot be realized.

In the fourth configuration, a target position / posture setting unit for setting the target position and the target posture of the robot working end, and the next target position and target posture based on the current target position and target posture of the robot working end. A next position / posture generation unit, a robot inverse kinematics calculation unit that calculates, for each joint, the displacement amount of the joint that realizes the next target position and target posture calculated by the next position / posture generation unit, The robot inverse kinematics calculation unit determines whether or not the amount of displacement of the joint exceeds the motion limit for each joint by the axis motion limit judgment unit and the axis motion limit judgment unit. When the joint exceeds the motion limit, the final position and orientation generation unit that calculates the final position and orientation of the working end for display and the final position and orientation generation unit calculate the final position and orientation. And a screen display unit for displaying a message indicating that it is difficult to set the robot working end to the target position and the target posture while displaying the final position and posture of the working end. Characterize.

In the fifth structure, in addition to the fourth structure, when the displacement amount of the joint calculated by the robot inverse kinematics calculation unit exceeds the motion limit, the final working end is determined. A position and orientation, and an operation mode setting unit that sets a mode in which the message is displayed on the screen display unit, and the final position and orientation generation unit includes the calculated final position and orientation of the working end, or , The message indicating that it is difficult to set the robot work end to the target position and the target posture is displayed on the screen display unit according to the mode set by the operation mode setting unit. It is characterized by displaying.

[0016]

The present invention thus configured operates as follows for each configuration.

First, in the first configuration, when the calculated displacement amount exceeds each indirect motion limit, or when the displacement amount cannot be calculated, the instructed position and posture of the end of work are determined. Since the fact that it cannot be realized is displayed, the operator can easily determine what causes the instructed posture to be impossible.

In the second configuration, when the calculated displacement amount exceeds each indirect motion limit, the joint is moved to the motion limit and the state is displayed, and
By displaying that there are joints that exceed the movement limit, the operator can easily determine what causes the instructed posture to be unrealized, and which joints exceed the movement limit. Will also be able to judge easily.

In the third configuration, even when the calculated displacement amount exceeds each indirect motion limit, the motion limit is ignored, the joint is moved, the state is displayed, and an instruction is given. Since it is displayed that the position and orientation of the working end cannot be realized, the operator can easily determine what causes the instructed attitude to be unrealized.
It also becomes possible to easily judge which joint exceeds the motion limit. Further, it becomes possible to understand the relationship with the mechanical limit.

In the fourth configuration, the next position / posture generation unit calculates the next target position and target posture from the target position and target posture of the robot working end set by the target position / posture setting unit, and the robot inverse kinematics is calculated. The calculation unit calculates the displacement amount of the joint that realizes the next target position and target posture for each joint. The axis motion limit determination unit determines for each joint whether or not the displacement amount of the joint calculated by the robot inverse kinematics calculation unit exceeds the motion limit, and one of the joints determines the motion limit. If it exceeds, the final position and orientation of the working end for display is calculated by the final position and orientation generation unit. The screen display unit displays the calculated final position and orientation of the working end, and also displays a message indicating that it is difficult to set the robot working end to the target position and target posture.

Therefore, the operator can easily determine what causes the instructed posture to be unrealizable.

In the fifth configuration, in the fourth configuration, when the displacement amount of the joint calculated by the robot inverse kinematics calculation unit exceeds the motion limit, the final position of the working end is determined. An operation mode setting unit for setting a posture and a mode of displaying the message on the screen display unit is added. For this purpose, the final position / posture generation unit calculates the final position and posture of the working end, or
Both or either of the messages indicating that it is difficult to set the robot working end to the target position and the target posture is displayed on the screen display unit according to the mode set by the operation mode setting unit. Can be made.

Therefore, the operator can easily determine what causes the instructed posture cannot be realized.
Further, it becomes possible to easily determine which joint exceeds the motion limit.

[0024]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of a robot motion simulation apparatus according to the present invention.

A target position / orientation setting unit 10 in the figure is a portion where an operator gives a target position and orientation of a working end (hand) of a robot, and is generally like a computer keyboard. is there. The operation mode setting unit 12
This is a part for setting eight kinds of operation modes as shown in FIG. This operation mode will be described later in detail.

The final position / posture generation unit 14 inputs the target position and posture set by the target position / posture setting unit 10, the initial position and posture, and the operation mode set by the operation mode setting unit 12. , To calculate the final robot posture. The final position / posture generation unit 14 also has a function of outputting the current position and posture of the hand.

The next position / posture generation unit 16 inputs the current position and posture of the hand output from the final position / posture generation unit 14, and then inputs the next position / posture such as an intermediate point between the present position and the target position. To calculate the final position and orientation generation unit 14
This is output to. Although the detailed reason for providing the next position / posture generating unit 16 will be described later, even when the target position / posture of the hand cannot be realized, the hand position can be set within a range that does not exceed the mechanical limit points of the axes constituting the robot. This is so that the position and orientation can be displayed.

The robot inverse kinematics calculation unit 20 is
Based on the next position / posture output from the next position / posture generation unit 16, the displacement amount of each joint for setting the hand in this position / posture is calculated, and the inverse kinematics solution as the calculation result is It is output to the final position / posture generation unit 14.

The axis motion limit determination unit 22 determines whether or not there is an axis exceeding the motion limit based on the displacement amount of each joint calculated by the robot inverse kinematics calculation unit 20, and the result is determined by the robot. Inverse kinematics calculator 2
It outputs to 0.

The screen display unit 24 includes the final position / posture generation unit 1.
The final position and orientation of the hand calculated by 4 are displayed, and the operator looks at this screen to determine whether the motion path of the robot is proper.

The apparatus of the present invention thus constructed operates as follows based on the flow charts shown in FIGS. 3 and 4.

In order to verify what the movement of the robot displayed on the screen looks like, first, the operator inputs data regarding the target position and posture of the hand, which is the working end, to the target position / posture setting unit 10. Start by entering (S1
1). The robot inverse kinematics calculation unit 20 inputs data relating to the target position and posture of this hand via the final position / posture generation unit 14, and based on the input data, calculates the displacement amount of each joint constituting the robot. The inverse kinematics for calculation is solved (S12). As a result of this calculation, when the axis motion limit determination unit 22 determines that the displacement amounts of all the joints are within the motion limits, and the inverse kinematics solution can also be obtained, the robot operates normally. Therefore, the final position / posture generation unit 14 moves the hand to the target position and posture, and displays this state on the screen display unit 24 (S13, S14).

On the other hand, the robot inverse kinematics calculator 2
Although the inverse kinematics solution could be calculated by 0, if one of the axes exceeds the motion limit, in other words, if the motion limit of the joint is widened, the hand is moved to the target position and posture. If it can be set, the final posture of the robot and the like are displayed according to the mode set by the operation mode setting unit 12.

In such a case, it is possible to set six kinds of modes 1 to 6 as shown in FIG.
For example, when the mode 1 is set, when one of the axes exceeds the movement limit, the posture of the robot displayed on the screen display unit 24 is left as it is and "there is an axis exceeding the movement limit. "Cannot operate" is displayed on the screen. This message allows the operator to easily know that it is impossible to set the hand at the target position and posture. In the case of mode 2, instead of the above message, only the axes that exceed the operation limit are displayed in different colors.

When the mode 3 is selected, the joints exceeding the movement limit are displayed by operating the robot up to the limit value, and at the same time, a screen indicating that "there is no movement because there are axes exceeding the movement limit" Display on top.

When mode 4 is selected, instead of the above message, only axes that exceed the operation limit are displayed in different colors.

When the mode 5 is selected, the robot is operated and displayed while ignoring the operation restriction, and at the same time, "the operation cannot be performed because there is an axis exceeding the operation limit" is displayed on the screen.

When mode 6 is selected, instead of the above message, only the axes that exceed the operation limit are displayed in different colors.

In this way, if the mode is selected as necessary, the reason why the target position cannot be reached can be easily analyzed.
It becomes possible to easily determine what kind of the optimum robot is and how the optimum route can be realized (S15, S16).

Further, the robot inverse kinematics calculation unit 2
When the inverse kinematics solution cannot be calculated by 0, that is, when the hand cannot be set to the target position and posture in any way, the mode 7 or the mode 8 as shown in FIG. It is possible to set the type. For example, when the mode 7 is set, the posture of the robot displayed on the screen display unit 24 is left as it is, and “the robot does not reach it by any means” is displayed on the screen. From this message, the operator can know that it is impossible to set the robot hand to the target position and posture (S16, S1).
7).

In the case of the mode 8, for the joints exceeding the movement limit, the robot is operated up to the limit value and displayed, and at the same time, the message "the robot does not reach even if it tries" is displayed on the screen (S16, S17). .

In this case, it is necessary to move the axis exceeding the motion limit to the motion limit. A flowchart for moving the axis is shown in FIG.

In this flowchart, Tcur0 indicates the position and posture of the hand immediately before starting this processing, and Tgoal0 indicates the position and posture of the target hand set by the target position / posture setting unit 10. Tcur represents the current position and posture of the hand, and Tgoal represents the current target position and posture corresponding to the next position and posture calculated by the next position and posture generation 16. Is shown.

When this process is started, first, as initial setting, Tgoal = Tgoal0 and Tcur = Tc.
The setting of ur0 is performed. That is, the current target position and posture are set as the set target hand position and posture, and the current hand position and posture are set as the hand position and posture immediately before starting this process (S20). ). Next, an intermediate position and posture T between the current position and posture of the hand and the target hand position and posture are obtained. This intermediate position / orientation calculation is expressed by a 6-dimensional vector of yaw, pitch, and roll angle representing the position vector and attitude, and the intermediate vector of the two 6-dimensional vectors is taken as an intermediate value, and the next position / orientation generation unit 16 It is performed (S21). The robot inverse kinematics calculation unit 20 performs calculation based on this data regarding the next position and orientation. As a result, if the inverse kinematics solution does not exist, it is impossible to set the hand at this position and posture. Therefore, the above calculation is performed for this intermediate position and posture T of the target hand. It is performed after resetting the position and orientation Tgoal. In other words, the inverse kinematics solution is calculated for the position, posture and intermediate position of the hand immediately before starting this processing, and the intermediate position and posture for the posture T. This process is repeated until the inverse kinematics solution is calculated (S22, S2).
3).

As a result of the judgment in the step S21, when the inverse kinematics solution exists, the difference between the intermediate position and the posture T and the intermediate position and the posture Tc calculated immediately before is determined by the predetermined position, The value of this Tc is set as the final position and orientation of the robot, provided that it is within the minimum change amount ε of orientation (S24). Until the difference between the intermediate position / posture T and the intermediate position / posture Tc calculated immediately before is within the minimum change amount ε, the above calculation is repeated until the intermediate position / posture T becomes the current hand. It is performed after resetting the position and posture Tcur of. That is, the inverse kinematics solution is calculated for the intermediate position and posture T and the intermediate position and posture between the target hand position and the posture Tgoal0. This process is repeated until the difference between the intermediate position / posture T and the intermediate position / posture Tc calculated immediately before becomes within the minimum change amount ε (S24, S25).

Since the final position of the hand is obtained by the above processing, the robot having the posture based on this final position is displayed to inform the operator that the robot can be moved only up to this point. Therefore, the operator can refer to this state and refer to the optimum robot type and the optimum route.

[0047]

As described above, according to the present invention, the following effects are obtained for each claim. According to the configuration of claim 1, when the calculated displacement amount exceeds each indirect motion limit, or when the displacement amount cannot be calculated, it is said that the instructed end position and posture cannot be realized. Since it is displayed, the operator can easily determine what causes the instructed posture cannot be realized.

According to the second aspect of the present invention, when the calculated displacement exceeds the indirect motion limit, the joint is moved to the motion limit to display the state, and the joint exceeding the motion limit is detected. By displaying the fact that it exists, the operator can easily determine what causes the instructed posture cannot be realized, and also easily determine which joint exceeds the motion limit. Will be able to.

According to the third aspect of the present invention, even when the calculated displacement amount exceeds each indirect motion limit, the motion limit is ignored, the joint is moved, the state is displayed, and the instruction is given. Since it is displayed that the position and posture of the working end cannot be realized, the operator can easily determine what causes the instructed posture to be unrealized, and which joint exceeds the motion limit. You will be able to easily judge whether or not. Further, it becomes possible to understand the relationship with the mechanical limit.

In the structure of claim 4, when any joint exceeds the motion limit, the final position and orientation of the working end for display is calculated by the final position and orientation generating unit, The screen display unit displays the calculated final position and posture of the working end, and also displays a message indicating that it is difficult to set the robot working end to the target position and the target posture. Therefore, the operator can easily determine what causes the instructed posture to be unrealizable.

According to the fifth aspect of the present invention, when the amount of displacement of the joint calculated by the robot inverse kinematics calculation unit exceeds the movement limit, the final position and posture of the working end and the message are transmitted. An operation mode setting unit for setting the mode to be displayed on the screen display unit is added, and the final position and posture of the working end calculated in the final position and posture generating unit or the robot working end is set to the target position and the target posture. Since either or both of the messages indicating that it is difficult to set to and are displayed on the screen display unit according to the mode set by the operation mode setting unit, the operator does not It is possible to easily determine whether or not the instructed posture cannot be realized due to, and it is also easy to determine which joint exceeds the movement limit. It becomes possible.

[Brief description of drawings]

FIG. 1 is a schematic configuration block diagram of a robot motion simulation apparatus according to the present invention.

FIG. 2 is a diagram showing an example of an operation mode that can be set by an operation mode setting unit shown in FIG.

FIG. 3 is a flowchart of a method for simulating a robot operation according to the present invention.

FIG. 4 is a flowchart of a method for simulating a robot operation according to the present invention.

FIG. 5 is a flowchart showing a simulation of a conventional robot operation.

[Explanation of symbols]

 10 ... Target position / orientation setting unit, 12 ... Operation mode setting unit, 14 ... Final position / orientation generation unit, 16 ... Next position / orientation generation unit 20 ... Robot inverse kinematics calculation unit, 22 ... Axis motion limit determination unit, 24 ... Screen Display section.

Claims (5)

[Claims] 1. A method of simulating a robot operation for studying application of a robot to an environment of an installation site and studying an optimal work route, which comprises instructing a position and a posture of a robot working end and determining a position based on the command. Calculate the displacement amount for each joint to achieve the posture, and if the calculated displacement amount exceeds the indirect motion limit, or if the displacement amount cannot be calculated, the specified work end A method for simulating a robot movement, which displays that the position and orientation cannot be realized. 2. A method of simulating a robot operation for studying application of a robot to an environment of an installation site and studying an optimum work route, which comprises instructing a position and a posture of a robot working end and determining a position based on the instruction. The displacement amount for each joint to realize the posture is calculated, and when the calculated displacement amount exceeds the indirect motion limit, the joint is moved to the motion limit and the state is displayed. A method of simulating a robot motion, which is characterized by displaying that there are joints exceeding the motion limit. 3. A method of simulating a robot operation for studying application of a robot to an environment of an installation site and studying an optimal work route, which comprises instructing a position and a posture of a robot working end and determining a position based on the instruction. The displacement amount for each joint to realize the posture is calculated, and even if the calculated displacement amount exceeds the indirect motion limit, the motion limit is ignored and the joint is moved.
A method of simulating a robot operation, characterized in that the state is displayed and the fact that the designated position and orientation of the work end cannot be realized is displayed. 4. A next position and posture are calculated from a target position and posture setting unit (10) for setting a target position and a target posture of the robot working end, and a current target position and target posture of the robot working end. Next position / posture generator (1
4) and a robot inverse kinematics calculation unit (2) that calculates, for each joint, the displacement amount of the joint that realizes the next target position and target posture calculated by the next position / posture generation unit (14).
0) and the axis motion limit determination unit (2) that determines whether or not the displacement amount of the joint calculated by the robot inverse kinematics calculation unit (20) exceeds the motion limit for each joint.
2) and the final position / orientation for calculating the final position and attitude of the working end for display when any joint exceeds the operation limit by the axis operation limit determination unit (22). Displaying the final position and orientation of the work end calculated by the generation unit (14) and the final position and orientation generation unit (14), and setting the robot work end to the target position and target posture. Screen display section (2) that displays a message indicating that
4) A robot motion simulation apparatus comprising: 5. The robot inverse kinematics calculator (2)
When the displacement amount of the joint calculated by (0) exceeds the operation limit, the operation mode setting unit (the operation mode setting unit that sets the final position and posture of the working end and the mode in which the message is displayed on the screen display unit ( 12), and it is difficult for the final position / posture generating unit (14) to set the calculated final position and posture of the working end or the robot working end to the target position and the target posture. 5. The robot operation according to claim 4, characterized in that both or either of the messages indicating that is displayed on the screen display unit (24) according to the mode set by the operation mode setting unit. Simulation device.