DESC:FIELD
The present disclosure relates to the field of measurement methods for components to be machined.
DEFINITION
As used in the present disclosure, the following terms are generally intended to have the meaning as set forth below, except to the extent that the context in which they are used indicate otherwise.
Degrees of Freedom (DOF) – The term ‘Degrees of Freedom’ is referred as each of a number of independently variable factors affecting the range of states in which a system may exist. More particularly, any of the directions in which independent motion of a body can occur.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
Currently used method for machining a component such as a cast component involves initially measuring the offset distances of the component in a pitch axis, a roll axis and a yaw axis. The offset distances are measured with the help of contact methods such as a touch method or a probe method, or non–contact methods such as with the help of a laser. More specifically, only the linear offset distances of the component to be machined are measured in the three directions. For carrying out machining of the component, a robot is incorporated. A path for traversing by the robot is computed which needs to be adjusted. However, if the robot path is adjusted solely based on the linear offset distances, there is possibility of the robot path being either over adjusted or under adjusted. Further, machining of the component is dependent on the adjusted robot path. Hence, any offset distances computed based solely on the linear offset distances results in inaccurate machining of the component.
There is therefore, felt a need of a method for sensing orientation of a component to be machined, that alleviates the aforementioned drawbacks.
OBJECTS
Some of the objects of the present disclosure are described herein below:
An object of the present disclosure is to provide a method for sensing orientation of a component that offers increased accuracy in adjusting the robot path of the component.
Another object of the present disclosure is to provide a method for sensing orientation of a component that reduces machining costs.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure discloses a method for sensing orientation of a component to be machined, the method comprising the steps of:
displacing a robotic arm to a first set of predetermined locations corresponding to a pitch axis, a roll axis and a yaw axis of the component;
measuring by a profile sensor, angular offset distances of the component in the direction of each of the axes of the component;
setting a program for a robotic path to be followed by the robotic arm;
displacing the robotic arm to a second set of predetermined locations along the pitch, roll and yaw directions respectively of the component;
measuring by the profile sensor, linear offset distances of the component at the second set of predetermined locations in the direction of each of the axes of the component; and
calibrating the robotic path of the robot arm by taking into consideration the angular offset distances and the linear offset distances of the component.
In a preferred embodiment, the method includes a step of machining the component based on the adjustment of the program and desired tolerances.
In a preferred embodiment, the step of calibrating the program of the robotic path of the robot path is configured to be computer controlled.
The present disclosure discloses an apparatus for sensing orientation of a component to be machined, the apparatus comprising:
a component mounted on a platform;
a profile sensor mounted on a robotic arm configured to be displaced, wherein the profile sensor is configured to sense and measure the angular offset distances of the component and the linear offset distances of the component, in the direction of each of the axes of the component; and
a control panel configured to be in electronic communication with the profile sensor, the control panel configured to store and adjust a program of a path traveled by the robotic arm for carrying out machining operation on the component.
In a preferred embodiment, wherein the control panel is controlled by a user.
In a preferred embodiment, the profile sensor is configured to be displaced to a first set of predetermined locations to sense and measure the angular offset distances of the component in the direction of each of the axes of the component.
In a preferred embodiment, the profile sensor is configured to be displaced to a second set of predetermined locations to sense and measure the linear offset distances of the component in the direction of each of the axes of the component.
In a preferred embodiment, the program is adjusted based on the angular offset distances and the linear offset distances for performing machining operation on the component.
In a preferred embodiment, the control panel includes a computer-aided-drafting module and a computer-aided-manufacturing module for allowing a user to control the operation of the profile sensor.
BRIEF DESCRIPTION OF ACCOMPANYING DRAWING
A method for sensing orientation of components to be machined, of the present disclosure, will now be described with the help of the accompanying drawing, in which:
Figure 1 shows a view of the setup, in accordance with an embodiment of the present disclosure;
Figure 2 shows a view of the component of figure 1;
Figure 3 illustrates coplanarity measured at points on a surface without taking into consideration the angular offset distances of the component, of the prior art; and
Figures 4 illustrates coplanarity measured at the points on a surface taking into consideration the angular offset distances of the component, of the present disclosure.
LIST OF REFERENCE NUMERALS
100 – apparatus
10 – platform
20 – component
30 – machining head
40 – robot arm
50 – profile sensor
60 – predetermined location
X – pitch axis
Y – roll axis
Z – yaw axis
DETAILED DESCRIPTION
Embodiments, of the present disclosure, will now be described with reference to the accompanying drawing.
Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, elements, components, and/or groups thereof. The particular order of steps disclosed in the method and process of the present disclosure is not to be construed as necessarily requiring their performance as described or illustrated. It is also to be understood that additional or alternative steps may be employed.
When an element is referred to as being "mounted on," “engaged to,” "connected to," or "coupled to" another element, it may be directly on, engaged, connected or coupled to the other element. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed elements.
The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component, region, layer or section from another component, region, layer or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.
Terms such as “inner,” “outer,” "beneath," "below," "lower," "above," "upper," and the like, may be used in the present disclosure to describe relationships between different elements as depicted from the figures.
Referring to the figures 1 and 2, a method for sensing orientation of a component 20 to be machined. The method comprises the steps of:
• displacing a robot arm 40 to a first set of predetermined locations corresponding to a pitch axis X, a roll axis Y and a yaw axis Z of the component 20;
• measuring by a profile sensor 50 to measure the angular offset distances of the component 20 in the direction of each of the axes X, Y, Z of the component 20;
• setting a program for a robotic path to be followed by the robot arm 40;
• displacing the robot arm 40 to a second set of predetermined locations along the X, Y and Z directions respectively of the component 20;
• measuring the linear offset distances of the component 20 at the second set of predetermined locations in the direction of each of the axes X, Y, Z of the component 20;
• calibrating the robotic path of the robot arm 40 by taking into consideration the angular offset distances and the linear offset distances of the component 20.
In a preferred embodiment, the method includes a step of machining the component 20 based on the adjustment of the program and desired tolerances.
In a preferred embodiment, the step of calibrating the program of the robotic path of the robotic arm 40 is configured to be computer controlled.
Further, the present disclosure discloses an apparatus 100 for sensing orientation of a component 20 to be machined. The apparatus 100 comprises a component 20 mounted on a platform 10, a profile sensor 50 mounted on a robot arm 40. A machining head 30 is attached to the robot arm 40 for performing machining operation on the component 20. The profile sensor 50 is attached to the machining head 30. The robot arm 40 is configured to be displaced in relation to the platform 10 for performing machining operation on the component 20. The profile sensor 50 is configured to sense and measure the angular offset distances of the component 20, and the linear offset distances of the component 20, in the direction of each of the pitch axis X, the roll axis Y, and the yaw axis Z of the component 20. The apparatus 100 comprises a control panel not shown in figures configured to be in electronic communication with the profile sensor 50. The control panel is configured to store and adjust a program of a path traveled by the robot arm 40 for carrying out machining operation on the component 20. The control panel is controlled by a user.
In a first step, the profile sensor 50 attached to the robot arm 40 is configured to be displaced at a first set of predetermined locations to sense and measure the angular offset distances of the component 20 in the direction of each of the pitch axis X, the roll axis Y, and the yaw axis Z of the component 20. This is needed to take into account the angular offset of the component 20 with respect to the pitch axis X, the roll axis Y, and the yaw axis Z of the component 20, and compensate for the angular offset. A setting of a program for a robotic path to be followed by the robot arm 40 is done. The angular offset of the component 20 is taken into consideration to adjust the amount of machining that needs to be carried out on the component 20. Failure to take into account the angular offset of the component 20 in the direction of the pitch axis X, roll axis Y, and yaw axis Z i.e. in pitch, roll and yaw directions of the component 20 results in inaccurate machining of the component 20. The existing apparatus 100 is not configured to take into account the angular offset distances of the component 20 in the direction of the pitch axis X, roll axis Y, and yaw axis Z i.e. in pitch, roll and yaw directions.
In a second step, the profile sensor 50 attached to the robot arm 40 is configured to be displaced to a second set of predetermined locations to sense and measure the linear offset distances of the component 20 in the direction of each of the pitch axis X, roll axis Y, and yaw axis Z of the component 20.
In a further third step, the program of the robotic path of the robot arm 40 is calibrated taking into consideration the angular offset distances and the linear offset distances of the component 20.
The first predetermined locations and the second predetermined locations are selected based on the construction of the cast component 20 to be machined, while taking into consideration any presence of defects in the casting. The first predetermined locations are selected to lie on a clean and defect-free area. Since, the first predetermined locations facilitate measuring angular offset distances of the component 20, increased accuracy is desired for measuring angles. For high accuracy, sufficient length of scan is highly desirable.
In a preferred embodiment, the control panel includes a computer-aided-drafting module and a computer-aided-manufacturing module for allowing a user to control the operation of the profile sensor. The displacement of the robot arm 40 is configured to be with respect to the axes of the component 20.
Existing methods rely on merely sensing the linear offset distances measured of the component 20 along the pitch axis X, roll axis Y, and yaw axis Z directions. However, the existing method does not take into account the angular offset distances of the component 20 with the respect to the pitch axis X, the roll axis Y, and the yaw axis Z of the component 20. More specifically, only the linear deviations are taken into account by the existing methods and the angular deviations are not. The present disclosure aims at overcoming this shortcoming of the existing method, by measuring the angular offset distances of the component 20 with respect to the pitch axis X, roll axis Y, and yaw axis Z. Thus, offset distances in all the six degrees of freedom i.e. three angular degrees of freedom and three translational degrees of freedom are taken into consideration in correcting the robotic path followed by the robot arm 40. The program is adjusted based on the angular offset distances and the linear offset distances for performing machining operation on the component.
EXPERIMENTAL DETAILS
Figures 3 of the prior art illustrates coplanarity measured at points (P1, P2, P3, P4, P5, P6, P7, P8, P9) on a surface of the component 20. Figure 3 illustrates coplanarity measured at points (P1, P2, P3, P4, P5, P6, P7, P8, P9) without sensing the angular offset distances. The profile sensor 50 is moved to a location 60 among the first set of predetermined locations for measuring the coplanarity of the points (P1, P2, P3, P4, P5, P6, P7, P8, P9) on the surface of the component 20. Column 2 of the table 1 shows corresponding measurements at the points (P1, P2, P3, P4, P5, P6, P7, P8, P9) with no angular offset incorporated. Measured value of coplanarity was observed to be 12.01 mm, as calculated taking into consideration the maximum and minimum values of distances of the points (P1, P2, P3, P4, P5, P6, P7, P8, P9). This coplanarity was measured over a 500 mm length of the surface of the component 20. The angular offset distance was observed to be 0.3 degrees.
Figures 4 of the present disclosure illustrates coplanarity measured at the points (P1, P2, P3, P4, P5, P6, P7, P8, P9). Figure 4 illustrates coplanarity measured at points (P1, P2, P3, P4, P5, P6, P7, P8, P9) with sensing the angular offset distances. The profile sensor 50 is moved to a location 60 among the first set of predetermined locations for measuring the coplanarity of the points (P1, P2, P3, P4, P5, P6, P7, P8, P9) on the surface of the component 20. Column 3 of the table 1 shows corresponding measurements at the points (P1, P2, P3, P4, P5, P6, P7, P8, P9) with angular offset incorporated. Measured value of coplanarity was observed to be 10.81 mm, as calculated by taking into consideration the maximum and minimum values of distances of the points (P1, P2, P3, P4, P5, P6, P7, P8, P9). Thus, the difference in coplanarity measured at the points (P1, P2, P3, P4, P5, P6, P7, P8, P9) was observed to be 12.01 less 10.81 i.e. 1.2 mm. The angular offset of 0.3 degrees was applied to the component 20. The corrected coplanarity was observed to be 10.81 mm after application of the angular offset of 0.3 degrees. Thus, the method of the present disclosure results in a decreased amount of machining operation needed to bring the component 20 into conformity.
Column 1 Column 2 Column 3
Sensing Point Sensed Values in mm
(without incorporating the angular offset distance in the direction of the pitch axis) Sensed Values in mm
(after incorporating the angular offset distance in the direction of the pitch axis)
P1 146.59 144.2
P2 151.4 150.06
P3 145.31 144.42
P4 147.1 147.28
P5 154.45 155.0
P6 143.47 144.39
P7 148.01 149.45
P8 142.44 144.39
P9 152.83 155.2
Min 142.44 144.39
Max 154.45 155.2
Coplanarity 12.01 10.81
Table 1 – comparison of coplanarity measured at locations on a surface of the component
The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.
TECHNICAL ADVANCEMENT
The present disclosure described herein above has several technical advantages including, but not limited to, the realization of a method for sensing orientation of components to be machined that:
• offers increased accuracy in machining components within desired tolerances;
• reduction in machining cost as number of passes required are reduced; and
• offers reduction in machining time as rework is reduced.
The foregoing description of the specific embodiments so fully reveals the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element or group of elements.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.
Any discussion of documents, acts, materials, apparatus, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation. ,CLAIMS:WE CLAIM:
1. A method for sensing orientation of a component (20) to be machined, said method comprising the steps of:
• displacing a robot arm (40) to a first set of predetermined locations corresponding to a pitch axis (X), a roll axis (Y) and a yaw axis (Z) of the component (20);
• measuring by a profile sensor, angular offset distances of the component (20) in the direction of each of the axes (X, Y, Z) of the component (20);
• setting a program for a robotic path to be followed by the robot arm (40);
• displacing the robot arm (40) to a second set of predetermined locations along the pitch (X), roll (Y) and yaw (Z) directions respectively of the component (20);
• measuring by the profile sensor 50, linear offset distances of the component (20) at the second set of predetermined locations in the direction of each of the axes (X, Y, Z) of the component (20);
• calibrating the robotic path of the robot arm by taking into consideration the angular offset distances and the linear offset distances of the component (20).
2. The method as claimed in claim 1 includes a step of machining the component (20) based on the adjustment of the program and desired tolerances.
3. The method as claimed in claim 1, wherein the step of calibrating the program of the robotic path of the robot arm is configured to be computer controlled.
4. An apparatus (100) for sensing orientation of a component (20) to be machined, said apparatus (100) comprising:
• a component (20) mounted on a platform (10);
• a profile sensor (50) mounted on a robot arm (40) configured to be displaced, wherein said profile sensor (50) is configured to sense and measure the angular offset distances of the component (20) and the linear offset distances of the component (20), in the direction of each of the axes (X, Y, Z) of the component (20); and
• a control panel configured to be in electronic communication with said profile sensor (50), said control panel configured to store and adjust a program of a path traveled by said robot arm (40) for carrying out machining operation on said component (20).
5. The apparatus (100) as claimed in claim 1, wherein said control panel is controlled by a user.
6. The apparatus (100) as claimed in claim 1, wherein said profile sensor (50) is configured to be displaced to a first set of predetermined locations to measure the angular offset distances of the component (20) in the direction of each of the axes (X, Y, Z) of the component (20).
7. The apparatus (100) as claimed in claim 1, wherein said profile sensor (50) is configured to be displaced to a second set of predetermined locations to measure the linear offset distances of the component (20) in the direction of each of the axes (X, Y, Z) of the component (20).
8. The apparatus (100) as claimed in claim 4, wherein said program is adjusted based on the angular offset distances and the linear offset distances for performing machining operation on the component (20).
9. The apparatus (100) as claimed in claim 1, wherein said control panel includes a computer-aided-drafting module and a computer-aided-manufacturing module for allowing a user to control the operation of said profile sensor (50).
Dated this 07th day of November, 2023

_______________________________
MOHAN RAJKUMAR DEWAN, IN/PA – 25
of R.K.DEWAN & CO.
Authorized Agent of Applicant