KR102216732B1 - Control Method of realistic simulation platform with load compensation mechanism - Google Patents

Abstract

The present invention relates to a motion platform and a control method thereof to which a load compensation mechanism is applied, and more particularly, to a lower body supporting a load and a load and maintaining a stationary state; An upper body positioned to be spaced apart from the lower body and outputting a motion; A plurality of driving units provided between the upper body and the lower body and outputting motion to the upper body; A load compensation unit provided between the upper body and the lower body to compensate for a load during a lowering operation and an upward operation of the upper body; And a motion controller and a load compensation controller for controlling final outputs for each of the driving units based on simulator feedback information.

Description

Control Method of realistic simulation platform with load compensation mechanism

The present invention relates to a control method of a motion platform to which a load compensation mechanism is applied.

The motion platform is a platform that enables the experiencer to feel realism even in a virtual space by performing an appropriate motion that mimics the movement of a specific object according to various situations in connection with virtual reality content. This platform is being used for a variety of purposes, including movies, entertainment, pilot training, and training special equipment experts.

Assuming that there is a virtual space implemented similar to the real world and a simulator that directs the situation that the experiencer wants to experience, the motion platform receives information about the experience situation from this simulator and outputs the corresponding motion in real time, allowing the experiencer to It plays a role in helping people to experience realistic experiences by receiving feelings similar to reality. At this time, the motion output performance varies depending on the designed mechanism of the motion platform and the performance of the applied driving unit.

In general, a motion platform applies a mechanism for arranging a drive unit in parallel between a lower body that supports all loads and maintains a stationary state and an upper body where motion output occurs. The degrees of freedom (DOF) that can be output from the upper body and motion output specifications are determined according to the applied driving unit and joint method. Here, by applying a mechanism that can compensate for a part of the weight of the load separately from the output of the driving unit, the target output specification can be satisfied even when a driving unit with a lower output than the existing one is applied. In addition, since the spring accumulated by the load compensation after the descending motion can greatly help to change the motion quickly when switching the rising motion, it can express more dynamic motion than before.

The mechanism of the motion platform refers to the mechanical structure of a hardware, and the original output performance can be further improved by applying an additional mechanical load compensation structure. However, if the motion platform is driven by simply applying it, the direct performance can be improved, but a more precise motion cannot be output. Rather, if the force of the load compensation acts in a direction different from the intention of the simulator, there is a problem that awkward motion may be output. In order to solve this problem, there is a method of adding a current or torque sensor to the driving unit separately from the encoder sensor used in the controller by installing it on the driving unit as a standard, which causes an increase in manufacturing cost.

A general motion platform control method is to design the kinematics and inverse kinematics of the platform, design the relational expression between motion and the output of each driving unit, and then apply a rotation encoder or a position sensor such as a linear linear displacement sensor to control the closed loop. There is a way. However, it is rare that a controller for a motion platform with a load compensation mechanism has been developed exclusively.

If a general controller is applied to a motion platform to which the load compensation mechanism is applied, the motion performance can be directly output in an improved state, but it becomes difficult to output a more precise motion. Rather, if the force of the load compensation acts in a direction different from the intention of the simulator, if the controller fails to reflect it, there is a problem of outputting awkward motion. In addition, if the weight of the experiencer is not reflected in the load compensation control, there is a problem that the level of output of different motions is different for each experiencer due to the influence of the weight of the experiencer.

Republic of Korea Patent Registration No. 1672899 Korean Patent Registration No. 1630783 Korean Patent Registration No. 1544383 Korean Registered Patent No. 1531656

Accordingly, the present invention has been devised to solve the conventional problems as described above, and according to an embodiment of the present invention, the experiencer's load measurement and motion control for a motion platform to which a load compensation spring mechanism is applied without additional sensors. The purpose of this is to provide a motion platform with a load compensation mechanism and a control method thereof, which provides a method and, when this control method is applied to a motion platform with a load compensation mechanism, enables more similar and precise motion output to the situation of a simulator. .

According to an embodiment of the present invention, an object of the present invention is to propose a control method in which the weight of an experienced user and the load compensation mechanism are compensated for a motion platform to which a load compensation mechanism is applied.

According to an embodiment of the present invention, it can be applied to a spring-based load compensation motion platform without the need to add a separate sensor or device, and the difference in motion according to the weight of the experiencer can be minimized, and mechanically increased compared to the same motion platform. Its purpose is to provide a motion platform to which a load compensation mechanism is applied, and a control method thereof, capable of more precise and realistic control with output specifications.

Meanwhile, the technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems that are not mentioned are clearly to those of ordinary skill in the technical field to which the present invention belongs from the following description. It will be understandable.

A first object of the present invention is to provide a motion platform, comprising: a lower body supporting a load and a load and maintaining a stationary state; An upper body positioned to be spaced apart from the lower body and outputting a motion; A plurality of driving units provided between the upper body and the lower body and outputting motion to the upper body; A load compensation unit provided between the upper body and the lower body to compensate for a load during a lowering operation and an upward operation of the upper body; And a motion controller and a load compensation controller that control the final output for each of the driving units based on the simulator feedback information. It may be achieved as a motion platform to which a load compensation mechanism is applied.

In addition, the load compensation controller may be characterized in that it calculates the final output based on an applied force obtained by subtracting the load compensation force by the load compensation unit from the weight of the upper body and the experienced person.

In addition, the load compensation unit is a spring positioned at the center of the upper body and the lower body, and the driving unit includes a first link member having one end connected to a first joint portion provided on one side of the upper surface of the lower body , A second link member having one end connected to the other end of the first link member and a second joint part, and a driving part for rotationally driving the first link member based on the first joint part, and the second link The other end of the member may be coupled to one side of the upper body by a third joint.

In addition, the plurality of driving units may be arranged to be uniformly spaced apart from each other in a circumferential direction at an outer peripheral portion between the upper body and the lower body.

In addition, the load compensation controller calculates the weight distribution ratio for each joint according to the posture, and based on the applied force, the weight distribution ratio, and the acceleration input information for the motion included in the simulator feedback information, each third joint It can be characterized by calculating the acting force.

And the load compensation controller is characterized in that it calculates the output torque to be output to each drive unit based on the force acting on each of the third joint and the angle of the first link member and the second link member. I can.

A second object of the present invention is a method for controlling a motion platform to which a load compensation mechanism according to the aforementioned first object is applied, the method comprising: measuring a weight of an experienced person; Calculating a weight distribution ratio for each joint according to the posture based on the motion platform posture information; Calculating an applied force minus the load compensation force by the load compensation unit to the weight of the upper body and the experienced person; And calculating a force acting on each joint based on the applied force and the weight distribution ratio for each joint to derive a final output for each driving unit; of a motion platform to which a load compensation mechanism is applied, comprising: It can be achieved as a control method.

And the step of measuring the weight, the first step of calculating the height reached the spring equilibrium point in the state that only the load by the weight of the upper body exists; A second step in which an experienced person boards the upper body; A third step of calculating the height at which the spring equilibrium point is reached in the state that only the upper body and the load by the weight of the experienced person are present; And a fourth step of calculating the weight of the experienced person based on the height difference in the first step and the height difference and the spring constant in the third step.

In addition, the calculation of the height may be characterized in that it is based on angle and position information measured by an encoder provided in the driving unit.

In addition, the deriving of the final output comprises calculating a force acting on each third joint based on the applied force, the weight distribution ratio, and acceleration input information for the motion included in the simulator feedback information. can do.

In addition, it may be characterized in that the output torque to be output to each driving unit is calculated based on the force acting on each of the third joints and the angles of the first link member and the second link member.

According to a motion platform to which a load compensation mechanism is applied and a control method thereof according to an embodiment of the present invention, a method for measuring a load of an experienced person and controlling motion is provided for a motion platform to which a load compensation spring mechanism is applied without additional sensors, If this control method is applied to a motion platform with a load compensation mechanism applied, it has the effect of enabling more precise motion output similar to that of the simulator.

In addition, according to the motion platform to which the load compensation mechanism is applied and the control method thereof according to an embodiment of the present invention, it is possible to provide a control method in which the weight of the experienced person and the load compensation mechanism are compensated for the motion platform to which the load compensation mechanism is applied. .

And, according to the motion platform to which the load compensation mechanism is applied and the control method thereof according to an embodiment of the present invention, it can be applied to the spring-based load compensation motion platform without the need to add additional sensors or devices, and according to the weight of the experienced person. The difference in motion can be minimized, and it has the effect of enabling more precise and realistic control with a mechanically increased output specification compared to the same motion platform.

On the other hand, the effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those of ordinary skill in the art from the following description. I will be able to.

The following drawings attached to the present specification illustrate preferred embodiments of the present invention, and serve to further understand the technical idea of the present invention together with the detailed description of the present invention, so the present invention is limited to the matters described in such drawings. And should not be interpreted.
1 is a front view of a motion platform to which a load compensation mechanism according to an embodiment of the present invention is applied,
2 is a partial front view of a motion platform to which a load compensation mechanism according to an embodiment of the present invention is applied,
3 is a plan view of a motion platform to which a load compensation mechanism excluding an upper body according to an embodiment of the present invention is applied,
4 is a block diagram of a control method of a load compensation motion platform according to an embodiment of the present invention;
Figure 5a is a schematic diagram showing the side of the load compensation motion platform when there is only a load by the weight of the upper body according to an embodiment of the present invention;
Figure 5b is a schematic diagram of a state in which the upper body is lowered to the lowest height in Figure 5a;
Figure 5c is a schematic diagram showing the side of the load compensation motion platform when there is only a load by the weight of the upper body and the experienced person;
6A is a schematic diagram showing a plane of a load compensation motion platform in a state where the center of gravity is shifted from the center according to an embodiment of the present invention;
6B is a schematic diagram showing a partial side view of a load compensation motion platform in a state where the center of gravity is shifted from the center according to an embodiment of the present invention.

The above objects, other objects, features, and advantages of the present invention will be easily understood through the following preferred embodiments related to the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed contents may be thorough and complete, and the spirit of the present invention may be sufficiently conveyed to those skilled in the art.

In the present specification, when a component is referred to as being on another component, it means that it may be formed directly on the other component or that a third component may be interposed between them. In addition, in the drawings, the thickness of the components is exaggerated for effective description of the technical content.

Embodiments described herein will be described with reference to cross-sectional views and/or plan views, which are ideal exemplary views of the present invention. In the drawings, the thicknesses of films and regions are exaggerated for effective description of technical content. Therefore, the shape of the exemplary diagram may be modified by manufacturing technology and/or tolerance. Accordingly, embodiments of the present invention are not limited to the specific form shown, but also include a change in form generated according to the manufacturing process. For example, an area shown at a right angle may be rounded or may have a shape having a predetermined curvature. Accordingly, regions illustrated in the drawings have properties, and the shapes of regions illustrated in the drawings are for exemplifying a specific shape of a device region and are not intended to limit the scope of the invention. In various embodiments of the present specification, terms such as first and second are used to describe various elements, but these elements should not be limited by these terms. These terms are only used to distinguish one component from another component. The embodiments described and illustrated herein also include complementary embodiments thereof.

The terms used in the present specification are for describing exemplary embodiments and are not intended to limit the present invention. In this specification, the singular form also includes the plural form unless specifically stated in the phrase. As used in the specification, "comprises" and/or "comprising" does not exclude the presence or addition of one or more other elements.

In describing the specific embodiments below, a number of specific contents have been prepared to explain the invention in more detail and to aid understanding. However, readers who have knowledge in this field to the extent that they can understand the present invention can recognize that it can be used without these various specific contents. In some cases, it is mentioned in advance that parts that are commonly known in describing the invention and are not largely related to the invention are not described in order to prevent confusion without any reason in describing the invention.

Hereinafter, the configuration and function of the motion platform 100 to which the load compensation mechanism according to an embodiment of the present invention is applied will be described.

According to an embodiment of the present invention, by applying the load compensation unit 30, a high motion output can be achieved even with a low specification driving unit, and economical efficiency and space efficiency can be satisfied.

According to the motion platform 100 to which the load compensation mechanism is applied according to an embodiment of the present invention, a mechanism capable of compensating a part of the weight of the load separately from the output of the driving unit is applied, and a driving unit having a lower output than the conventional one Even if it is applied, the target output specifications can be satisfied, and the load compensation unit 30 accumulated by the load compensation after the descending operation can greatly help in rapid motion change when switching the ascending operation, so it is more dynamic than before. In motion can be expressed.

In addition, according to the motion platform 100 to which the load compensation mechanism according to the embodiment of the present invention is applied, a load compensation unit 30 is placed between the upper body 70 and the lower body 10 of the motion platform 100 It is possible to compensate a part of the weight of the load, and because the load compensation unit 30 has a simple structure, it can be applied to most motion platforms at a low cost, and the required output specification of the driving unit is lowered, thereby reducing the cost of parts required for manufacturing. , Power consumption can be lowered by the output of the smaller drive unit, it can be easily applied to the existing motion platform, and it can produce a higher motion output, and the motion platform can express more stable and dynamic motion than before.

The load compensation unit 30 having the core technical features of the present invention is applicable to most types of existing motion platforms.

However, in the detailed contents for carrying out the invention, the application of the load compensation mechanism to the motion platform type based on the three-axis rotation motor drive unit 21 will be described as an example.

First, FIG. 1 shows a front view of a motion platform 100 to which a load compensation mechanism according to an embodiment of the present invention is applied. As shown in Figure 1, the motion platform 100 to which the load compensation mechanism according to the embodiment of the present invention is applied, as a whole, is an upper body 70, a lower body 10, a plurality of driving units 20, and a load compensation It can be seen that it may be configured to include a unit 30, a connection unit, and the like.

The lower body 10 is configured to support a load and a load and maintain a stationary state. In addition, the upper body 70 is positioned to be spaced apart from the lower body 10 to the upper side, and motion is output by the plurality of driving units 20.

And the driving unit 20 is provided between the upper body 70 and the lower body 10, and is configured to output a motion to the upper body 70. 2 shows a partial front view of a motion platform 100 to which a load compensation mechanism according to an embodiment of the present invention is applied. And Figure 3 shows a plan view of the motion platform 100 to which the load compensation mechanism is applied to the upper body 70 is excluded according to an embodiment of the present invention.

Each of the driving units 20 according to an embodiment of the present invention, as shown in FIGS. 1 to 3, has a first joint part 22 having one end provided on one side of the upper surface of the lower body 10 and consisting of a rotary joint. The first link member 23 to be connected, a second link member 25 at one end connected by a second joint part 24 consisting of the other end of the first link member 23 and a rotary joint, and a first The link member 23 is configured to include a driving part 21 for rotationally driving the first joint part 22 as a reference. In addition, the other end of the second link member 25 is coupled by a third joint part 36 composed of a spherical joint on one side when the upper body 70 is lowered.

In addition, as shown in FIG. 3, the plurality of driving units 20 may be formed in a form in which three are spaced uniformly spaced apart from each other in the circumferential direction in the outer peripheral portion between the upper body 70 and the lower body 10. Can be seen.

Therefore, the drive unit 21 and the link connection structure connected in parallel between the upper body 70 and the lower body 10 are the lower body 10-the driving part 21-the first joint part 22-the second joint part 24 -3rd joint part (36)-upper body (70) structure. If designed in this form, it is possible to design a motion platform 100 capable of three-axis motion in the direction of the roll, pitch, and gravity weight (z-axis) of the upper body 70.

The load compensation unit 30 according to the embodiment of the present invention may be composed of a spring 31 located at a central portion between the upper body 70 and the lower body 10.

At this time, the spring 31 must have a spring constant sufficient to support the upper body 70 within an available height without being positioned to the maximum or minimum height for the weight of the comprehensive range of the experienced person. As a result, the upper body 70 can perform a three-axis motion in the roll, pitch, and gravity axis directions.

And the motion platform 100 according to the embodiment of the present invention is configured to include a connection unit 60, as shown in FIGS. 1 and 2. This connection unit 60 couples a plurality of drive unit connection ends 62 for coupling each of the third joints 36 to the upper body 70, and the upper guide 40 to the center of the lower surface of the upper body 70 A plurality of spring connection ends 61 connecting the spring connection end 61, a ring-shaped connection member 64 coupled to surround the outer surface of the spring connection end 61, and a plurality of drive unit connection ends 62 to the ring-shaped connection member It may be configured to include a connection member (63).

Hereinafter, a method of controlling a motion platform to which the aforementioned load compensation mechanism is applied will be described. 4 is a block diagram showing a control method of a load compensation motion platform according to an embodiment of the present invention.

The control method for the motion platform to which the load compensation mechanism is applied is largely divided into a controller 40 for motion and a controller 50 for load compensation, and the final control output is the sum of the values output from these controllers 40 and 50. Is determined by The controller 40 for motion is similar to that of a general motion platform. The controller 50 for load compensation includes a total of three detailed control elements for measuring the weight of the experienced person, distribution of weight for each joint of the driving part according to the posture, and load compensation force by the spring.

The load compensation controller 40 according to the embodiment of the present invention calculates the final output based on the weight of the upper body 70 and the experienced person 1 minus the load compensation force by the load compensation unit 30 Is done.

That is, the load compensation controller 40 calculates the weight distribution ratio for each joint according to the posture, and based on the applied force and the weight distribution ratio and the acceleration input information for the motion included in the simulator feedback information, each third joint part 26 ) To calculate the force acting on it.

And the load compensation controller 40, based on the force acting on each of the third joint portion 26, and the angle of the first link member 23 and the second link member 25 to each driving unit 21 The output torque to be output is calculated.

In the method of controlling the motion platform to which the load compensation mechanism according to the embodiment of the present invention is applied, the weight of the experienced person is first measured. And based on the motion platform posture information, the weight distribution ratio for each joint according to the posture is calculated. And the weight of the upper body 70 and the experienced person 1 is calculated by subtracting the load compensation force by the load compensation unit 30. Further, the force acting on each third joint part 26 is calculated based on the applied force and the weight distribution ratio for each joint to derive the final output for each driving part 21.

In order to measure the weight of the experienced person 1, there is no additional sensor other than the encoder corresponding to the position sensor of the driving unit 21. The weight measurement method is measured by the following procedure.

First, the height of the upper body 70, which has reached the equilibrium point by the spring 31 for load compensation, is calculated in a state in which the experienced person 1 does not board and only the load by the weight of the upper body 70 exists. 5A is a schematic diagram showing a side surface of a load compensation motion platform when only a load by the weight of an upper body exists according to an embodiment of the present invention.

At this time, the upper body 70 must be maintained horizontally with the lower body 10, and the method of calculating the height of the upper body 70 is to receive the angle or position information of the current driving unit 221 measured from the encoder and receive the motion platform ( The height is calculated through the kinematic equation corresponding to 100).

Next, the upper body 70 is lowered as much as possible through simple height control of the driving unit 21 so that the experienced person 1 can board smoothly. Figure 5b is a schematic diagram showing a state in which the upper body is lowered to the lowest height in Figure 5a.

After the experienced person 1 boards, the control of the driving unit 21 is released. Finally, the height reached at the equilibrium point is calculated by the spring 31 for load compensation in the state where the load of the upper body 70 and the experienced person 1 is acting.

The force generated by the spring 31 is equal to the product of the spring displacement and the spring constant. According to this equation for the spring force, the weight of the experienced person can be measured as a product of the difference in height of the upper body 70 before and after boarding the experience person 1 and the spring constant.

In addition, the weight of each joint of the driving part according to the posture is shifted from the center of gravity of the upper body 70 to the center of the lower body 10 according to the posture of the upper body 70. At this time, the joint end of each driving part 21 The weight acting on the 3-joint 26 does not match and acts differently. 6A is a schematic diagram showing a plane of a load compensation motion platform in a state where the center of gravity is shifted from the center according to an embodiment of the present invention. And Figure 6b is a schematic diagram showing a partial side of the load compensation motion platform in a state in which the center of gravity is shifted from the center according to an embodiment of the present invention.

In order to compensate for this, the weight distribution ratio acting on each joint end (third joint part 26) is applied according to the posture of the upper body 70, and the value of the weight acting on each third joint part 26 by calculating each weight Is reflected in the load compensation.

In addition to the force distributed by the weight of the upper body 70 and the experienced person 1, a load compensation force by a spring acts on each of the third joints 26. Since this force acts between the center of the upper body 70 and the lower body 10, even if the posture of the upper body 70 is changed, it acts almost the same on all joints.

Since the force due to the weight (upper body + weight of the tester) and the direction in which the force for spring compensation is applied are different, the total force acting at the end of each third joint part 26 is calculated by calculating the difference in this force (acting force). You can get it. Based on this force and weight distribution ratio and acceleration input information for motion included in the simulator feedback information, control output values that should be output from each driving unit for load compensation are derived.

That is, based on the applied force (experienced weight + upper body weight-load compensation force), weight distribution ratio, and acceleration input information for the motion included in the simulator feedback information, the force acting on each third joint 26 is calculated. And, based on the force acting on each of the third joints 26 and the angles of the first link member 23 and the second link member 25, calculate the output torque to be output to each driving unit 26. do.

In addition, the above-described apparatus and method are not limitedly applicable to the configuration and method of the above-described embodiments, but all or part of each of the embodiments may be selectively combined so that various modifications can be made to the embodiments. It can also be configured.

1: Experiencer
10: lower body
20: drive unit
21: drive unit
22: first joint part
23: first link member
24: second joint part
25: second link member
26: 3rd joint part
30: load compensation unit
31: load compensation spring
40: spring upper guide
41: cylindrical part
42: upper flange portion
43: upper coupling end
44: upper mounting groove
45: upper guide guide slope
50: spring lower guide
51: cylinder
52: lower flange portion
53: bottom coupling end
54: spring departure prevention guide
55: Lower guide guide slope
60: connection unit
61: spring connection end
62: drive unit mounting end
63: connection member
64: ring-type connecting member
70: upper body
100: Motion platform to which load compensation mechanism is applied.

Claims (11)

delete delete delete delete delete delete A lower body supporting a load and a load and maintaining a stationary state, an upper body that is spaced apart from the lower body and outputs motion, and is provided between the upper body and the lower body, and outputs motion to the upper body. A plurality of driving units, a load compensation unit that is provided between the upper body and the lower body to compensate for the load when the upper body is lowered and when the upper body is raised, and a final output for each of the driving units based on simulator feedback information In the control method of a motion platform to which a load compensation mechanism including a motion controller and a load compensation controller is applied,
Measuring the weight of the experienced person;
Calculating a weight distribution ratio for each joint according to the posture based on the motion platform posture information;
Calculating an applied force minus the load compensation force by the load compensation unit to the weight of the upper body and the experienced person; And
Comprising the force acting on each joint based on the applied force and the weight distribution ratio for each joint, and deriving a final output for each driving unit; Including,
The step of measuring the weight,
A first step of calculating the height at which the spring equilibrium point is reached in the state that only the load by the weight of the upper body is present;
A second step in which an experienced person boards the upper body;
A third step of calculating the height at which the spring equilibrium point is reached in the state that only the upper body and the load by the weight of the experienced person are present;
And a fourth step of calculating the weight of the experienced person based on the height difference in the first step and the height difference and the spring constant in the third step. A method for controlling a motion platform using a load compensation mechanism, comprising: a.
delete The method of claim 7,
The calculation of the height is based on the angle and position information measured by an encoder provided in the driving unit. A method of controlling a motion platform to which a load compensation mechanism is applied.
The method of claim 9,
The step of deriving the final output,
Control of a motion platform applying a load compensation mechanism, characterized in that the force acting on each third joint is calculated based on the applied force, the weight distribution ratio, and the acceleration input information for the motion included in the simulator feedback information. Way.
The method of claim 10,
The motion platform to which the load compensation mechanism is applied, characterized in that the output torque to be output to each driving unit is calculated based on the force acting on each of the third joints and the angles of the first link member and the second link member. Control method.

Images