ShadowGage Sorters provide Precision, Speed and Versatility
Precision
ShadowGage sorters use a digital camera in conjunction with a specially designed optical system and proprietary software to measure dimensions on a part’s profile to an accuracy of +/-.0001″
The accuracy of the measurements is made possible by the combination of optical elements and a software package that accounts for the physical properties that create the image instead of simply just the image.
ShadowGage is not Machine Vision, but rather Precision Gaging Software. You may have noticed that many machine vision based system require adjustment to the light source or measure slightly different as the part moves across the field of view. This is because machine vision performs operations on the image, without regard to “how” the image was created, so the user needs to make adjustments to create an image that will measure correctly. Of course, every part is different, requiring different settings and full objectivity is never achieved.
In contrast, ShadowGage’s software incorporates the physical components that generate the image. Although by no means complete, the following examples will help clarify this concept:
Example 1:
Variations in focus generally create variations in measurements. Because inevitably different edges of the part are at different focal distances from the lens, it’s impossible to have the entire part with the same focus. While machine vision typically treats all edges the same, ShadowGage is programmed with the relation between focus and measurement and it compensates accordingly. Because every optical system is slightly different, ShadowGage measures these differences and stores them on a system by system basis.
Example 2:
Because light diffracts differently as it passes by a round edge versus a flat edge, the image it generates is slightly different, resulting in a variation in image. While machine vision treats all edges the same, ShadowGage discerns the type of edge that generated the image and compensates accordingly. As before, and because every optical system is different, ShadowGage measures and stores these differences on a system by system basis.
ShadowGage also compensates for other such physical variables, including lens distortion, the camera’s imager pixel boundary non-linearity, edge polarity, interference fringe formation at the imager, and many more.
The result is a measurement system that offers unequaled accuracy, and because it’s aware of the physical conditions that generate the image, it requires no other adjustment, making it a truly objective device.
In addition, all the measurement tools included in ShadowGage operate on the basis of mathematical regression, with a mechanism to remove outliers. This results in measurements that are not affected by small debris on the part or camera pixels that have a sightly different response.
The accuracy of the measurements is made possible by the combination of optical elements and a software package that accounts for the physical properties that create the image instead of simply just the image.
ShadowGage is not Machine Vision, but rather Precision Gaging Software. You may have noticed that many machine vision based system require adjustment to the light source or measure slightly different as the part moves across the field of view. This is because machine vision performs operations on the image, without regard to “how” the image was created, so the user needs to make adjustments to create an image that will measure correctly. Of course, every part is different, requiring different settings and full objectivity is never achieved.
In contrast, ShadowGage’s software incorporates the physical components that generate the image. Although by no means complete, the following examples will help clarify this concept:
Example 1:
Variations in focus generally create variations in measurements. Because inevitably different edges of the part are at different focal distances from the lens, it’s impossible to have the entire part with the same focus. While machine vision typically treats all edges the same, ShadowGage is programmed with the relation between focus and measurement and it compensates accordingly. Because every optical system is slightly different, ShadowGage measures these differences and stores them on a system by system basis.
Example 2:
Because light diffracts differently as it passes by a round edge versus a flat edge, the image it generates is slightly different, resulting in a variation in image. While machine vision treats all edges the same, ShadowGage discerns the type of edge that generated the image and compensates accordingly. As before, and because every optical system is different, ShadowGage measures and stores these differences on a system by system basis.
ShadowGage also compensates for other such physical variables, including lens distortion, the camera’s imager pixel boundary non-linearity, edge polarity, interference fringe formation at the imager, and many more.
The result is a measurement system that offers unequaled accuracy, and because it’s aware of the physical conditions that generate the image, it requires no other adjustment, making it a truly objective device.
In addition, all the measurement tools included in ShadowGage operate on the basis of mathematical regression, with a mechanism to remove outliers. This results in measurements that are not affected by small debris on the part or camera pixels that have a sightly different response.
Speed
While most systems of commensurate accuracy use a linear array (line-scan) camera, ShadowGage Sorters use a digital array camera.
The reason for use of a linear array camera is that it’s much easier to make accurate measurements because only the central portion of the optics are used, and the configuration of the linear array permits a contiguous pixel geometry, which makes calculations linear in nature. However the drawback of line-scan cameras is that the part needs to be panned to create the final image, making it a slow process.
In contrast, ShadowGage uses an array camera, where the entire image image is obtained without the need to pan the part, and it’s of course, much faster. Not only it’s faster to acquire the image, but it can also be done while the part is in motion, which is impossible with line-scan systems.
Also, ShadowGage’s transport is designed to provide constant speed, which in turn makes it possible not to have to wait for a part to be ejected before the next one can be inspected. Also because of the constant transport speed, the position of each part on the transport can be calculated, and an air ejector triggered when the part is exactly in front of it. The use of an air eject is faster than moving a steering gate.
The reason for use of a linear array camera is that it’s much easier to make accurate measurements because only the central portion of the optics are used, and the configuration of the linear array permits a contiguous pixel geometry, which makes calculations linear in nature. However the drawback of line-scan cameras is that the part needs to be panned to create the final image, making it a slow process.
In contrast, ShadowGage uses an array camera, where the entire image image is obtained without the need to pan the part, and it’s of course, much faster. Not only it’s faster to acquire the image, but it can also be done while the part is in motion, which is impossible with line-scan systems.
Also, ShadowGage’s transport is designed to provide constant speed, which in turn makes it possible not to have to wait for a part to be ejected before the next one can be inspected. Also because of the constant transport speed, the position of each part on the transport can be calculated, and an air ejector triggered when the part is exactly in front of it. The use of an air eject is faster than moving a steering gate.
Versatility
ShadowGage is offered in two configurations, for two very distinct part geometries.
Flat platen sorters are ideal for use with parts that have a “flat end” and are not too long. The requirement is that the part must be stable standing on the platen. If the part can stand on the platen, then it can be inspected, almost independently of the rest of the part’s geometry.
Tilted platen sorters are used in conjunction with parts that do not have a “flat edge” or have a large length to diameter ratio.
With either system, the measurements to be performed on each part can be saved as an inspection program for that part, and be easily recalled at any time.
ShadowGage sorters can be used with manual or bulk feed. In the manual mode, parts are simply placed on the transport and ShadowGage does the rest. For fully automated unassisted use, a bulk feed system such as vibratory feeder or conveyor can easily be used to load parts onto the transport. It is generally very easy to load parts onto ShadowGage. For cases where part orientation is an issue for the feeder, ShadowGage has the capability to sort regardless of orientation.
Because in the manual mode no tooling is required, ShadowGage sorters can readily be used to:
Flat platen sorters are ideal for use with parts that have a “flat end” and are not too long. The requirement is that the part must be stable standing on the platen. If the part can stand on the platen, then it can be inspected, almost independently of the rest of the part’s geometry.
Tilted platen sorters are used in conjunction with parts that do not have a “flat edge” or have a large length to diameter ratio.
With either system, the measurements to be performed on each part can be saved as an inspection program for that part, and be easily recalled at any time.
ShadowGage sorters can be used with manual or bulk feed. In the manual mode, parts are simply placed on the transport and ShadowGage does the rest. For fully automated unassisted use, a bulk feed system such as vibratory feeder or conveyor can easily be used to load parts onto the transport. It is generally very easy to load parts onto ShadowGage. For cases where part orientation is an issue for the feeder, ShadowGage has the capability to sort regardless of orientation.
Because in the manual mode no tooling is required, ShadowGage sorters can readily be used to:
- Sort relatively small lots.
- Sort parts for which the bulk feed is not yet available.
- Sort lots where mixed product is suspected.