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Joey
Is there any limits to what it can make? Is it illegal to make certain things out of the 3D printer? If so,tell me. How much money is a 3D printer?If I put a puppy in the scanner, would it be able to replicate the puppy? How does the 3-D printer know if something should move or not?
Answer
Let me answer your questions one at a time:
1. Is there any limits to what it can make?
Right now, yes. In the future, no. The technology today is not advanced enough to make anything. The most common materials used now are plastic, resin, and recently the technology has grown to include metal. Food (lots of chocolate) has recently been printed as have organic materials such as stem cells. However, right now the biggest constraints of 3D printing is size. Soon one can conceivably print things as big as buildings, but for now most printers are relatively small (12in.X12in. though there are some much larger commercial printers). The future of 3D printing will also allow for printing on a molecular level, but for now the technology can only print in the micro scale.
2. Strictly speaking there are no laws against printing anything in 3D. However, laws exist that prohibit the manufacturing of certain goods and these apply to things that a 3D printer can conceivably make. An example of something that is illegal to print in the U.S. is a full gun. One can print parts of a gun legally, but cannot print a whole gun.
3. The cost of a 3D printer varies greatly. One can buy a 3D printer for the home for as little as $499. Commercial 3D printers cost much more and can run upwards of $30,000. With the continual advancement of the technology you can expect to see the prices drop as time goes on.
4. If you scan a puppy in 3D, a printer can print it in 3D. It would most likely be made out of plastic or resin though, not nice soft puppy fur.
5. 3D printers can print moving parts. When an item is programed into the software it maps out exactly where to lay down material. Because 3D printing is additive manufacturing it doesn't print the parts one by one, but instead prints the whole object layer by successive layer. If the programing is correct then moving parts can be included in the printed final product.
Let me answer your questions one at a time:
1. Is there any limits to what it can make?
Right now, yes. In the future, no. The technology today is not advanced enough to make anything. The most common materials used now are plastic, resin, and recently the technology has grown to include metal. Food (lots of chocolate) has recently been printed as have organic materials such as stem cells. However, right now the biggest constraints of 3D printing is size. Soon one can conceivably print things as big as buildings, but for now most printers are relatively small (12in.X12in. though there are some much larger commercial printers). The future of 3D printing will also allow for printing on a molecular level, but for now the technology can only print in the micro scale.
2. Strictly speaking there are no laws against printing anything in 3D. However, laws exist that prohibit the manufacturing of certain goods and these apply to things that a 3D printer can conceivably make. An example of something that is illegal to print in the U.S. is a full gun. One can print parts of a gun legally, but cannot print a whole gun.
3. The cost of a 3D printer varies greatly. One can buy a 3D printer for the home for as little as $499. Commercial 3D printers cost much more and can run upwards of $30,000. With the continual advancement of the technology you can expect to see the prices drop as time goes on.
4. If you scan a puppy in 3D, a printer can print it in 3D. It would most likely be made out of plastic or resin though, not nice soft puppy fur.
5. 3D printers can print moving parts. When an item is programed into the software it maps out exactly where to lay down material. Because 3D printing is additive manufacturing it doesn't print the parts one by one, but instead prints the whole object layer by successive layer. If the programing is correct then moving parts can be included in the printed final product.
tell me the difference :)?
I AM VIETN
Between normal X-ray technology and Computed Tomography used in hospital , especially about Computer Function of CT
thanks
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Small suggestion :)
Are you having blog , could you invite me as your friend :)
Answer
Standard x-rays are simple images similar to photographs taken in the X-ray spectrum of light.
Computed tomography (CT), originally known as computed axial tomography (CAT or CT scan) and body section roentgenography, is a medical imaging method employing tomography where digital geometry processing is used to generate a three-dimensional image of the internals of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation. The word "tomography" is derived from the Greek tomos (slice) and graphia (to write). CT produces a volume of data which can be manipulated, through a process known as windowing, in order to demonstrate various structures based on their ability to block the X-ray beam. Although historically the images generated were in the axial or transverse plane (orthogonal to the long axis of the body), modern scanners allow this volume of data to be reformatted in various planes or even as volumetric (3D) representations of structures.
Although most common in healthcare, CT is also used in other fields, for example nondestructive materials testing.
Advantages Over Projection Radiography
First, CT completely eliminates the superimposition of images of structures outside the area of interest. Second, because of the inherent high-contrast resolution of CT, differences between tissues that differ in physical density by less than 1% can be distinguished. Third, data from a single CT imaging procedure consisting of either multiple contiguous or one helical scan can be viewed as images in the axial, coronal, or sagittal planes, depending on the diagnostic task. This is referred to as multiplanar reformatted imaging.
Regarding your question about the computing portion, X-ray slice data is generated using an X-ray source that rotates around the object; X-ray sensors are positioned on the opposite side of the circle from the X-ray source. Many data scans are progressively taken as the object is gradually passed through the gantry. They are combined together by the mathematical procedure known as tomographic reconstruction.
Newer machines with faster computer systems and newer software strategies can process not only individual cross sections but continuously changing cross sections as the gantry, with the object to be imaged, is slowly and smoothly slid through the X-ray circle. These are called helical or spiral CT machines. Their computer systems integrate the data of the moving individual slices to generate three dimensional volumetric information (3D-CT scan), in turn viewable from multiple different perspectives on attached CT workstation monitors.
CT scanner with cover removed to show the principle of operation
CT scanner with cover removed to show the principle of operation
In conventional CT machines, an X-ray tube and detector are physically rotated behind a circular shroud (see the image above right); in the electron beam tomography (EBT) the tube is far larger and higher power to support the high temporal resolution. The electron beam is deflected in a hollow funnel shaped vacuum chamber. X-rays are generated when the beam hits the stationary target. The detector is also stationary.
The data stream representing the varying radiographic intensity sensed reaching the detectors on the opposite side of the circle during each sweep is then computer processed to calculate cross-sectional estimations of the radiographic density, expressed in Hounsfield units. Sweeps cover 360 or just over 180 degrees in conventional machines, 220 degrees in EBT.
CT is used in medicine as a diagnostic tool and as a guide for interventional procedures. Sometimes contrast materials such as intravenous iodinated contrast are used. This is useful to highlight structures such as blood vessels that otherwise would be difficult to delineate from their surroundings. Using contrast material can also help to obtain functional information about tissues.
Pixels in an image obtained by CT scanning are displayed in terms of relative radiodensity. The pixel itself is displayed according to the mean attenuation of the tissue(s) that it corresponds to on a scale from -1024 to +3071 on the Hounsfield scale. Pixel is a two dimensional unit based on the matrix size and the field of view. When the CT slice thickness is also factored in, the unit is known as a Voxel, which is a three dimensional unit. The phenomenon that one part of the detector cannot differ between different tissues is called the Partial Volume Effect. That means that a big amount of cartilage and a thin layer of compact bone can cause the same attenuation in a voxel as hyperdense cartilage alone. Water has an attenuation of 0 Hounsfield units (HU) while air is -1000 HU, cancellous bone is typically +400 HU, cranial bone can reach 2000 HU or more (os temporale) and can cause artefacts. The attenuation of metallic implants depends on atomic number of the element used: Titanium usually has an amount of +1000 HU, iron steel can completely extinguish the X-ray and is therefore responsible for well-known line-artifacts in computed tomogrammes.
Standard x-rays are simple images similar to photographs taken in the X-ray spectrum of light.
Computed tomography (CT), originally known as computed axial tomography (CAT or CT scan) and body section roentgenography, is a medical imaging method employing tomography where digital geometry processing is used to generate a three-dimensional image of the internals of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation. The word "tomography" is derived from the Greek tomos (slice) and graphia (to write). CT produces a volume of data which can be manipulated, through a process known as windowing, in order to demonstrate various structures based on their ability to block the X-ray beam. Although historically the images generated were in the axial or transverse plane (orthogonal to the long axis of the body), modern scanners allow this volume of data to be reformatted in various planes or even as volumetric (3D) representations of structures.
Although most common in healthcare, CT is also used in other fields, for example nondestructive materials testing.
Advantages Over Projection Radiography
First, CT completely eliminates the superimposition of images of structures outside the area of interest. Second, because of the inherent high-contrast resolution of CT, differences between tissues that differ in physical density by less than 1% can be distinguished. Third, data from a single CT imaging procedure consisting of either multiple contiguous or one helical scan can be viewed as images in the axial, coronal, or sagittal planes, depending on the diagnostic task. This is referred to as multiplanar reformatted imaging.
Regarding your question about the computing portion, X-ray slice data is generated using an X-ray source that rotates around the object; X-ray sensors are positioned on the opposite side of the circle from the X-ray source. Many data scans are progressively taken as the object is gradually passed through the gantry. They are combined together by the mathematical procedure known as tomographic reconstruction.
Newer machines with faster computer systems and newer software strategies can process not only individual cross sections but continuously changing cross sections as the gantry, with the object to be imaged, is slowly and smoothly slid through the X-ray circle. These are called helical or spiral CT machines. Their computer systems integrate the data of the moving individual slices to generate three dimensional volumetric information (3D-CT scan), in turn viewable from multiple different perspectives on attached CT workstation monitors.
CT scanner with cover removed to show the principle of operation
CT scanner with cover removed to show the principle of operation
In conventional CT machines, an X-ray tube and detector are physically rotated behind a circular shroud (see the image above right); in the electron beam tomography (EBT) the tube is far larger and higher power to support the high temporal resolution. The electron beam is deflected in a hollow funnel shaped vacuum chamber. X-rays are generated when the beam hits the stationary target. The detector is also stationary.
The data stream representing the varying radiographic intensity sensed reaching the detectors on the opposite side of the circle during each sweep is then computer processed to calculate cross-sectional estimations of the radiographic density, expressed in Hounsfield units. Sweeps cover 360 or just over 180 degrees in conventional machines, 220 degrees in EBT.
CT is used in medicine as a diagnostic tool and as a guide for interventional procedures. Sometimes contrast materials such as intravenous iodinated contrast are used. This is useful to highlight structures such as blood vessels that otherwise would be difficult to delineate from their surroundings. Using contrast material can also help to obtain functional information about tissues.
Pixels in an image obtained by CT scanning are displayed in terms of relative radiodensity. The pixel itself is displayed according to the mean attenuation of the tissue(s) that it corresponds to on a scale from -1024 to +3071 on the Hounsfield scale. Pixel is a two dimensional unit based on the matrix size and the field of view. When the CT slice thickness is also factored in, the unit is known as a Voxel, which is a three dimensional unit. The phenomenon that one part of the detector cannot differ between different tissues is called the Partial Volume Effect. That means that a big amount of cartilage and a thin layer of compact bone can cause the same attenuation in a voxel as hyperdense cartilage alone. Water has an attenuation of 0 Hounsfield units (HU) while air is -1000 HU, cancellous bone is typically +400 HU, cranial bone can reach 2000 HU or more (os temporale) and can cause artefacts. The attenuation of metallic implants depends on atomic number of the element used: Titanium usually has an amount of +1000 HU, iron steel can completely extinguish the X-ray and is therefore responsible for well-known line-artifacts in computed tomogrammes.
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Title Post: Can someone answer my questions about the 3-D printer?
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Author: Yukie
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Rating: 100% based on 99998 ratings. 5 user reviews.
Author: Yukie
Thanks For Coming To My Blog
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