阅读说明：本技术 基于视觉引导的机器人的磨料水射流去毛刺系统和方法 (Abrasive water jet deburring system and method based on vision-guided robot ) 是由 李兴成 荀康迪 周豪 梁栋 于 2019-10-16 设计创作，主要内容包括：本发明提供了一种基于视觉引导的机器人的磨料水射流去毛刺系统和方法,所述系统包括：多工位工作盘、上料机器人、视觉检测器、加工机器人、下料机器人和控制器,其中,多工位工作盘用于放置加工产品,视觉检测器检测用于处于检测位置的待加工产品,控制器用于控制多工位工作盘将待加工产品依次送到上料位置、检测位置、加工位置,以及将已加工产品送到下料位置,并用于根据检测的结果控制加工机器人通过磨料水射流加工待加工产品。本发明能够提高产品加工的可靠性和稳定性,并能够提高生产效率,降低生产成本,同时能够实现各种复杂曲面的加工,并保证对加工产品无亚表面损伤,还能够提高抛光精度,避免产生边界效应。(The invention provides an abrasive water jet deburring system and method based on a vision-guided robot, wherein the system comprises: the multi-station working disc is used for placing machining products, the vision detector is used for detecting the to-be-machined products at the detection positions, the controller is used for controlling the multi-station working disc to sequentially send the to-be-machined products to the feeding positions, the detection positions and the machining positions, and send the machined products to the discharging positions, and the machining robot is controlled to machine the to-be-machined products through abrasive water jet according to the detection results. The invention can improve the reliability and stability of product processing, improve the production efficiency, reduce the production cost, simultaneously realize the processing of various complex curved surfaces, ensure no sub-surface damage to the processed products, improve the polishing precision and avoid the generation of boundary effect.)

1. A robot abrasive water jet deburring system based on visual guidance, comprising:

a multi-station working disc;

the feeding robot is used for placing a product to be processed into a station on the multi-station working disc, wherein the station is at a feeding position;

a vision detector for detecting the product to be processed at a detection position;

the processing robot is used for processing the product to be processed at the processing position;

a blanking robot for taking out the processed product at a blanking position;

a controller, the controller respectively with multistation working disc the material loading robot vision detector machining robot with unloading robot links to each other, the controller is used for control multistation working disc will treat that the processing product sends to in proper order the material loading position detect the position the processing position, and will the processing product is sent to the unloading position, and be used for the basis the result control that detects the machining robot passes through abrasive material water jet machining treat the processing product.

2. The vision-guidance-based robotic abrasive water jet deburring system of claim 1 wherein said multi-station work disc comprises:

the four stations are respectively and uniformly arranged on the upper part of the multi-station working disc corresponding to the feeding position, the detection position, the processing position and the discharging position;

the driving motor is arranged inside the multi-station working disc and is used for driving the multi-station working disc to rotate;

the water tank is arranged at the bottom of the multi-station working plate and used for storing water and waste materials generated during processing.

3. The vision-guidance-based robot abrasive water jet deburring system of claim 2, wherein the controller is specifically configured to control the driving motor to drive the multi-station working disc to rotate 90 ° in each operation, so as to control each station of the multi-station working disc to sequentially pass through the feeding position, the detection position, the machining position and the blanking position, and to acquire an image of the product to be machined through the vision detector, obtain position information of burrs of the product to be machined according to the image and a stored standard image of the product to be machined, and then process the position information of the burrs through a conversion algorithm, so as to obtain a coordinate position of the burrs in the machining robot base coordinate system, and send the coordinate position information to the machining robot.

4. The vision guidance-based robotic abrasive water jet deburring system of claim 3 wherein said multi-station work disc comprises a circular work disc.

5. The vision guidance-based robotic abrasive water jet deburring system of claim 4 further comprising:

the storage table for the products to be processed is arranged corresponding to the feeding robot and used for placing the products to be processed;

and the processed product storage table is arranged corresponding to the blanking robot and used for placing the processed product.

6. The vision guidance-based robotic abrasive water jet deburring system of claim 5 wherein said vision detector comprises an illuminator, a CCD camera and a photosensor.

7. The vision guidance-based robotic abrasive water jet deburring system of claim 6 wherein said machining robot includes a nozzle, an abrasive means, a water flow tube and a pressure regulating means.

8. A vision guidance-based robotic abrasive water jet deburring method based on the vision guidance-based robotic abrasive water jet deburring system of any one of claims 1-7 comprising:

placing a product to be processed into a station on a multi-station working disc at a feeding position through a feeding robot, and then sending the product to be processed to a detection position through the multi-station working disc;

detecting the product to be processed through a visual detector, and then sending the product to be processed to a processing position through the multi-station working disc;

processing the product to be processed by adopting abrasive water jet according to the detection result through a processing robot, and then sending the processed product to a blanking position through the multi-station working disc;

and taking out the processed product at the blanking position by a blanking robot.

9. The vision-guidance-based robot abrasive water jet deburring method of claim 8, wherein the multi-station working disc sends the product to be machined to a machining position, a detection position and a machined product to a blanking position, and the multi-station working disc is driven to rotate 90 degrees at each operation by a driving motor arranged in the multi-station working disc so as to send the product to be machined to the detection position, the machining position and the machined product to the blanking position in sequence.

10. The vision-guidance-based robot abrasive water jet deburring method of claim 8, wherein the detection of the product to be machined by the vision detector specifically comprises:

acquiring an image of the product to be processed through the visual detector and sending the image to a controller;

the controller obtains the position information of the burrs of the product to be processed according to the image and the stored standard image of the product to be processed;

and the controller processes the position information of the burr through a conversion algorithm to obtain the coordinate position of the burr in the base coordinate system of the processing robot and sends the coordinate position to the processing robot.

Technical Field

The invention relates to the technical field of deburring processing, in particular to a grinding material water jet deburring system of a robot based on visual guidance and a grinding material water jet deburring method of the robot based on visual guidance.

Background

In automobile safety, ABS automobile anti-lock braking systems are an important component. The ABS anti-lock braking system for automobile can automatically control the braking force when the automobile brakes, so that the wheels are not locked and are in a rolling and sliding state, the adhesion between the wheels and the ground is ensured to be at the maximum value, the wheels are prevented from sideslipping when the automobile brakes suddenly, and the automobile can still steer when braking. If an automobile ABS system needs to work normally, wheel speed data of wheels must be collected uninterruptedly, a gear ring is an important part for transmitting the wheel speed data to a sensor, and the gear ring and a wheel hub are arranged on the inner side of the wheel hub in an interference fit mode.

However, when the gear ring is milled, end surface burrs generally exist more or less, and the existence of the burrs causes deformation of the gear ring after installation, so that the acquisition of a wheel speed signal is influenced, the function of an ABS system is reduced, and the service life of the system is shortened. Therefore, the processing quality of the gear ring can directly influence the normal driving of the automobile and the personal safety of drivers. At present burring in-process, even also be difficult to get rid of the burr completely with the vibration burring, moreover, adopt artifical burring to need use instruments such as steel rule, slide caliper to detect the burr, generally hardly find the burr accurately, not only can not reach the purpose of complete burring, and inefficiency moreover, intensity of labour is big, waste time and energy, has improved the work piece cost.

Disclosure of Invention

The present invention is directed to solving, at least to some extent, one of the technical problems in the art described above. Therefore, an object of the present invention is to provide an abrasive water jet deburring system based on a vision-guided robot, which can improve the reliability and stability of product processing, improve production efficiency, reduce production cost, and simultaneously can realize processing of various complex curved surfaces, ensure no sub-surface damage to the processed product, and also can improve polishing precision, and avoid boundary effect.

The second purpose of the invention is to provide an abrasive water jet deburring method based on a vision-guided robot.

In order to achieve the above object, a first aspect of the present invention provides an abrasive water jet deburring system based on a vision-guided robot, including a multi-station working disc; the feeding robot is used for placing a product to be processed into a station on the multi-station working disc, wherein the station is at a feeding position; a vision detector for detecting the product to be processed at a detection position; the processing robot is used for processing the product to be processed at the processing position; a blanking robot for taking out the processed product at a blanking position; a controller, the controller respectively with multistation working disc the material loading robot vision detector machining robot with unloading robot links to each other, the controller is used for control multistation working disc will treat that the processing product sends to in proper order the material loading position detect the position the processing position, and will the processing product is sent to the unloading position, and be used for the basis the result control that detects the machining robot passes through abrasive material water jet machining treat the processing product.

According to the abrasive water jet deburring system based on the vision-guided robot, the machined product is placed through the multi-station working disc, the product to be machined at the detection position is detected through the vision detector, the multi-station working disc is controlled through the controller to sequentially send the product to be machined to the feeding position, the detection position and the machining position, the machined product is sent to the discharging position, and the machining robot is controlled to machine the product to be machined through the abrasive water jet according to the detection result, so that the reliability and the stability of product machining can be improved, the production efficiency can be improved, the production cost can be reduced, machining of various complex curved surfaces can be realized, sub-surface damage to the machined product is avoided, the polishing precision can be improved, and the boundary effect is avoided.

In addition, the abrasive water jet deburring system based on the vision-guided robot proposed by the above embodiment of the invention can also have the following additional technical features:

according to one embodiment of the invention, the multi-station work disc comprises: the four stations are respectively and uniformly arranged on the upper part of the multi-station working disc corresponding to the feeding position, the detection position, the processing position and the discharging position; the driving motor is arranged inside the multi-station working disc and is used for driving the multi-station working disc to rotate; the water tank is arranged at the bottom of the multi-station working plate and used for storing water and waste materials generated during processing.

According to an embodiment of the present invention, the controller is specifically configured to control the driving motor to drive the multi-station working disc to rotate 90 ° each time, so as to control each station of the multi-station working disc to sequentially pass through the feeding position, the detection position, the processing position, and the discharging position, and is configured to acquire an image of the product to be processed by the vision detector, obtain position information of a burr of the product to be processed according to the image and a stored standard image of the product to be processed, then process the position information of the burr by using a conversion algorithm, so as to obtain a coordinate position of the burr in the base coordinate system of the processing robot, and send the coordinate position to the processing robot.

Further, the multi-station working disc comprises a circular working disc.

Further, the abrasive water jet deburring system based on the vision-guided robot further comprises: the storage table for the products to be processed is arranged corresponding to the feeding robot and used for placing the products to be processed; and the processed product storage table is arranged corresponding to the blanking robot and used for placing the processed product.

Further, the vision detector includes an illumination device, a CCD camera, and a photosensor.

Further, the processing robot comprises a nozzle, an abrasive device, a water flow pipe and a pressure regulating device.

In order to achieve the above object, a second embodiment of the present invention provides a method for deburring by abrasive water jet based on a vision-guided robot, including: placing a product to be processed into a station on a multi-station working disc at a feeding position through a feeding robot, and then sending the product to be processed to a detection position through the multi-station working disc; detecting the product to be processed through a visual detector, and then sending the product to be processed to a processing position through the multi-station working disc; processing the product to be processed by adopting abrasive water jet according to the detection result through a processing robot, and then sending the processed product to a blanking position through the multi-station working disc; and taking out the processed product at the blanking position by a blanking robot.

According to the abrasive water jet deburring method based on the vision-guided robot, the to-be-machined product is placed in the station at the feeding position on the multi-station working disc through the feeding robot, then the to-be-machined product is sent to the detection position through the multi-station working disc, then the to-be-machined product is detected through the vision detector, then the to-be-machined product is sent to the machining position through the multi-station working disc, the to-be-machined product is machined through the abrasive water jet by the machining robot according to the detection result, then the machined product is sent to the blanking position through the multi-station working disc, and finally the machined product at the blanking position is taken out through the blanking robot, so that the reliability and the stability of product machining can be improved, the production efficiency can be improved, the production cost can be reduced, and various complex curved surfaces can be machined at the same time, and the method ensures that the machined product has no sub-surface damage, can also improve the polishing precision and avoid generating boundary effect.

In addition, the abrasive water jet deburring method based on the vision-guided robot proposed by the above embodiment of the invention can also have the following additional technical features:

further, the multistation working disc will wait to process the product and send the machined position, detect the position and will process the product and send the unloading position to, specifically through set up in the drive motor drive of working at every turn in the multistation working disc rotates 90, in order to with wait that the machined product sends in proper order the detection position the machining position, and will the machined product sends the unloading position.

Further, the detecting the product to be processed through the visual detector specifically includes: acquiring an image of the product to be processed through the visual detector and sending the image to a controller; the controller obtains the position information of the burrs of the product to be processed according to the image and the stored standard image of the product to be processed; and the controller processes the position information of the burr through a conversion algorithm to obtain the coordinate position of the burr in the base coordinate system of the processing robot and sends the coordinate position to the processing robot.

Drawings

FIG. 1 is a block schematic diagram of an abrasive water jet deburring system based on a vision-guided robot according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of the positions of the components of the abrasive water jet deburring system based on the vision-guided robot according to one embodiment of the present invention;

FIG. 3 is a top view of the structure of an abrasive water jet deburring system based on a vision-guided robot in accordance with one embodiment of the present invention;

FIG. 4 is a side view of the structure of a vision-guided robot-based abrasive water jet deburring system in accordance with one embodiment of the present invention;

FIG. 5 is a schematic illustration of a ring gear according to an embodiment of the present invention;

FIG. 6 is a flow chart of an abrasive water jet deburring method based on a vision-guided robot according to an embodiment of the present invention;

fig. 7 is a flowchart of a method of inspecting a product to be processed by a visual inspection apparatus according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Fig. 1 is a block schematic diagram of an abrasive water jet deburring system based on a vision-guided robot according to an embodiment of the present invention.

As shown in fig. 1, the abrasive water jet deburring system based on the vision-guided robot according to the embodiment of the present invention includes a multi-station work tray 10, a feeding robot 20, a vision detector 30, a machining robot 40, a blanking robot 50, and a controller 60. The feeding robot 20 is used for placing a product to be processed into a station on the multi-station working plate 10, wherein the station is located at a feeding position; the vision detector 30 is used for detecting the product to be processed at the detection position; the processing robot 40 is used for processing a product to be processed at a processing position; the blanking robot 50 is used for taking out the processed product at the blanking position; the controller 60 is respectively connected with the multi-station working disc 10, the feeding robot 20, the vision detector 30, the machining robot 40 and the discharging robot 50, and the controller 60 is used for controlling the multi-station working disc 10 to sequentially send a product to be machined to the feeding position, the detection position and the machining position, sending the machined product to the discharging position, and controlling the machining robot 40 to machine the product to be machined through abrasive water jet according to the detection result.

In one embodiment of the present invention, the multi-station work tray 10 may include four stations, a drive motor, and a water bath. As shown in fig. 2, the four stations can be respectively and uniformly arranged on the upper part of the multi-station working plate 10 corresponding to the loading position a, the detection position B, the processing position C and the unloading position D; a driving motor (not shown in the figures) can be arranged inside the multi-station working disc 10 and is used for driving the multi-station working disc 10 to rotate; a water tank (not shown) may be provided at the bottom of the multi-station work tray 10 for storing water and waste generated during processing.

Further, as shown in fig. 2, the feeding robot 20, the vision detector 30, the processing robot 40, and the discharging robot 50 may be uniformly disposed around the multi-station processing tray 10 corresponding to the feeding position a, the detection position B, the processing position C, and the discharging position D, respectively, and a gap is reserved at an upper portion of the multi-station processing tray 10, so that the gap may be used for heat dissipation, and may be used for discharging water and waste generated during processing into a water tank.

In an embodiment of the present invention, referring to fig. 2, the controller 60 may be specifically configured to control the driving motor to drive the multi-station work tray 10 to rotate 90 ° each time, so as to control each station on the multi-station work tray 10 to sequentially pass through the feeding position a, the detecting position B, the processing position C, and the discharging position D, and may be configured to collect an image of a product to be processed by the vision detector 30, obtain position information of a burr of the product to be processed by comparing the collected image with a stored standard image of the product to be processed, and then process the position information of the burr by using a conversion algorithm, so as to obtain coordinates of the burr in the machining robot base coordinate system, and send the coordinates to the machining robot 40.

Further, the processing robot 40 may control the end effector, that is, the water jet device, to be quickly positioned to the position of the burr according to the coordinate of the burr of the product to be processed in the basic coordinate system of the processing robot, and process the burr of the product to be processed by the abrasive water jet. The abrasive water jet is used for removing burrs of a product to be machined, machining of various complex curved surfaces can be achieved, sub-surface damage to the machined product is avoided, meanwhile, polishing precision can be improved, and boundary effect is avoided.

In one embodiment of the present invention, as shown in fig. 3, the abrasive water jet deburring system based on the vision-guided robot may further include a to-be-machined product storage table 70 and a machined product storage table 80. The to-be-processed product storage table 70 is arranged corresponding to the feeding robot 20 and used for placing the to-be-processed product; the processed product storage table 80 is provided corresponding to the blanking robot 50, and is used for placing the processed product.

Specifically, as shown in fig. 3, the products to be processed may be placed in a palletized state in the product-to-be-processed storage table 70, and the processed products may be placed in a palletized state in the processed product storage table 80.

In one embodiment of the present invention, the multi-station work discs 10 may comprise circular work discs.

In one embodiment of the present invention, as shown in fig. 4, the vision detector 30 may include an illumination Device 301, a CCD (Charge Coupled Device) camera 302, and a photosensor (not shown).

In one embodiment of the present invention, the processing robot 40 may include a nozzle, an abrasive device, a water flow pipe, and a pressure regulating device.

Based on the above structure, the gear ring shown in fig. 5 is taken as a substitute machining product, and the working process of the abrasive water jet deburring system based on the vision-guided robot of the invention is further explained in conjunction with fig. 4.

As shown in fig. 5, the ring gear includes an inner contour and an outer contour, and when the ring gear is deburred, it is necessary to detect the positions of the burrs on the inner contour and the outer contour of the ring gear and perform machining.

Firstly, the standard image of the gear ring shown in fig. 5 needs to be stored in a product database of the controller, then the system is started through the controller, and system self-checking is performed, so that the system enters a working state.

Further, as shown in fig. 4, the controller 60 may send a feeding control instruction to the feeding robot 20, control the feeding robot 20 to grab the product to be processed from the product storage table 70, that is, to put the gear ring to be processed into the feeding position, that is, the working position a, and then control the driving motor inside the multi-station working plate 10 to work, that is, drive the multi-station working plate to rotate 90 ° to send the product to be processed to the detection position, that is, the working position B.

Further, as shown in fig. 4, the vision detector 30 may collect an image of the ring gear to be machined by the monocular camera and transmit the image to the controller 60, the controller 60 may program and call a HALCON dynamic link library DLL file using vb. The position information of the burr in the gear ring to be processed is obtained by comparing the image of the gear ring to be processed with the stored gear ring standard image, the position information is converted into the coordinate position in the coordinate system of the processing robot tool by the relevant conversion algorithms such as hand-eye calibration, the coordinate of the burr position of the gear ring to be processed in the coordinate system of the processing robot base is further obtained and sent to the processing robot 40, and meanwhile, the controller 60 can control the driving motor in the multi-station working disc 10 to work, namely, the multi-station working disc is driven to rotate by 90 degrees so as to send a product to be processed, namely the gear ring to be processed to a processing position, namely a C working position.

Further, as shown in fig. 4, the machining robot 40 may rapidly position the end effector, i.e., the water jet cutting device, to the position of the burr of the gear ring to be machined according to the coordinates, and eject the high-pressure water jet with the abrasive through the nozzle, for example, the high-pressure water jet with the abrasive may be ejected through the nozzle with a diameter of 0.1mm to remove the burr of the gear ring to be machined, and send feedback information to the controller 60 after completing the deburring operation, and the controller 60 may control the driving motor inside the multi-station working disc 10 to operate, i.e., drive the multi-station working disc to rotate by 90 ° to send the machined gear ring to the blanking position, i.e., the D working position, after receiving the feedback information.

Further, as shown in fig. 4, the controller 60 sends a blanking control command to the blanking robot 50, and controls the blanking robot 50 to take out and put the processed ring gear at the blanking position, i.e., the D working position, into the processed product storage table 80, and simultaneously, the processed waste and water flow into the water tank 101.

It should be noted that, after the controller controls the multi-station working disc to send the product to be processed to the processing station from the loading position, the controller may control the loading robot to continue to grab the next product to be processed from the product storage table to be processed and place the next product to be processed into the multi-station working disc located at the loading position, and control the product to be processed to perform detection, processing and unloading after the last product to be processed. By circulating the above-mentioned machining process, machining efficiency can be improved.

According to the abrasive water jet deburring system based on the vision-guided robot, provided by the embodiment of the invention, the machined product is placed through the multi-station working disc, the product to be machined at the detection position is detected through the vision detector, then the multi-station working disc is controlled by the controller to sequentially send the product to be machined to the feeding position, the detection position and the machining position, the machined product is sent to the discharging position, and the machining robot is controlled to machine the product to be machined through the abrasive water jet according to the detection result, so that the reliability and the stability of product machining can be improved, the production efficiency can be improved, the production cost can be reduced, the machining of various complex curved surfaces can be realized, the condition that no sub-surface damage is caused to the machined product can be ensured, the polishing precision can be improved, and the boundary effect can be avoided.

Corresponding to the abrasive water jet deburring system based on the vision-guided robot provided by the embodiment, the embodiment of the invention also provides an abrasive water jet deburring method based on the vision-guided robot.

As shown in fig. 6, an abrasive water jet deburring method based on a vision-guided robot according to an embodiment of the present invention includes:

and S1, placing the product to be processed into a station at the feeding position on the multi-station working disc through the feeding robot, and then sending the product to be processed to the detection position through the multi-station working disc.

And S2, detecting the product to be processed through a visual detector, and then sending the product to be processed to a processing position through a multi-station working disc.

Specifically, as shown in fig. 7, the detection of the product to be processed by the visual detector includes the steps of:

s201, collecting an image of a product to be processed through a visual detector and sending the image to a controller.

S202, the controller obtains the position information of the burrs of the product to be processed according to the image and the stored standard image of the product to be processed.

And S203, the controller processes the position information of the burr through a conversion algorithm to obtain the coordinate position of the burr in the base coordinate system of the machining robot and sends the coordinate position to the machining robot.

And S3, machining the product to be machined by adopting abrasive water jet through the machining robot according to the detection result, and then sending the machined product to a blanking position through the multi-station working disc.

And S4, taking out the processed product at the blanking position by the blanking robot.

In one embodiment of the invention, the multi-station working disc sends the product to be processed to the processing position, the detection position and the processed product to the blanking position, and particularly, a driving motor arranged in the multi-station working disc drives the multi-station working disc to rotate 90 degrees every time the driving motor works so as to send the product to be processed to the detection position, the processing position and the blanking position in sequence.

It should be noted that, after the controller controls the multi-station working disc to send the product to be processed to the processing station from the loading position, the controller may control the loading robot to continue to grab the next product to be processed from the product storage table to be processed and place the next product to be processed into the multi-station working disc located at the loading position, and control the product to be processed to perform detection, processing and unloading after the last product to be processed. By circulating the above-mentioned machining process, machining efficiency can be improved.

According to the abrasive water jet deburring method based on the vision-guided robot provided by the embodiment of the invention, a product to be machined is placed in a station at a feeding position on a multi-station working disc through a feeding robot, then the product to be machined is sent to a detection position through the multi-station working disc, then the product to be machined is detected through a vision detector, then the product to be machined is sent to a machining position through the multi-station working disc, the product to be machined is machined by adopting abrasive water jet according to the detection result through the machining robot, then the machined product is sent to a blanking position through the multi-station working disc, and finally the machined product at the blanking position is taken out through the blanking robot, so that the reliability and stability of product machining can be improved, the production efficiency can be improved, the production cost can be reduced, and various complex curved surfaces can be machined at the same time, and the method ensures that the machined product has no sub-surface damage, can also improve the polishing precision and avoid generating boundary effect.

In the present invention, unless otherwise expressly specified or limited, the term "coupled" is to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.