Main Page - Revision history

Guerin: /* MGH voxel numerical models for download */

2018-10-03T15:05:34Z

MGH voxel numerical models for download

← Older revision		Revision as of 11:05, 3 October 2018
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	* [https://phantoms.martinos.org/HS6_voxels MGH "HS6" voxel head + chest model (male, large size)]		* [https://phantoms.martinos.org/HS6_voxels MGH "HS6" voxel head + chest model (male, large size)]
	* [https://phantoms.martinos.org/DCA_voxels MGH "DCA" detailed voxel head model (female, medium size)]		* [https://phantoms.martinos.org/DCA_voxels MGH "DCA" detailed voxel head model (female, medium size)]
	* [https://phantoms.martinos.org/~~DBS_pop~~ DBS Virtual Population]		* [https://phantoms.martinos.org/DBS_virtual_population DBS Virtual Population]

	== 3D-printed phantoms construction tips ==		== 3D-printed phantoms construction tips ==

Guerin: /* MGH voxel numerical models for download */

2018-10-03T15:05:03Z

MGH voxel numerical models for download

← Older revision		Revision as of 11:05, 3 October 2018
Line 25:		Line 25:
	* [https://phantoms.martinos.org/HS6_voxels MGH "HS6" voxel head + chest model (male, large size)]		* [https://phantoms.martinos.org/HS6_voxels MGH "HS6" voxel head + chest model (male, large size)]
	* [https://phantoms.martinos.org/DCA_voxels MGH "DCA" detailed voxel head model (female, medium size)]		* [https://phantoms.martinos.org/DCA_voxels MGH "DCA" detailed voxel head model (female, medium size)]
	* [https://phantoms.martinos.org/~~DBS_virtual_population~~ DBS Virtual Population]		* [https://phantoms.martinos.org/DBS_pop DBS Virtual Population]

	== 3D-printed phantoms construction tips ==		== 3D-printed phantoms construction tips ==

Guerin: /* MGH voxel numerical models for download */

2018-10-03T15:04:46Z

MGH voxel numerical models for download

← Older revision		Revision as of 11:04, 3 October 2018
Line 25:		Line 25:
	* [https://phantoms.martinos.org/HS6_voxels MGH "HS6" voxel head + chest model (male, large size)]		* [https://phantoms.martinos.org/HS6_voxels MGH "HS6" voxel head + chest model (male, large size)]
	* [https://phantoms.martinos.org/DCA_voxels MGH "DCA" detailed voxel head model (female, medium size)]		* [https://phantoms.martinos.org/DCA_voxels MGH "DCA" detailed voxel head model (female, medium size)]
	* [https://phantoms.martinos.org/~~DBS_pop~~ DBS Virtual Population]		* [https://phantoms.martinos.org/DBS_virtual_population DBS Virtual Population]

	== 3D-printed phantoms construction tips ==		== 3D-printed phantoms construction tips ==

Guerin: /* MGH voxel numerical models for download */

2018-10-03T14:42:17Z

MGH voxel numerical models for download

← Older revision		Revision as of 10:42, 3 October 2018
Line 25:		Line 25:
	* [https://phantoms.martinos.org/HS6_voxels MGH "HS6" voxel head + chest model (male, large size)]		* [https://phantoms.martinos.org/HS6_voxels MGH "HS6" voxel head + chest model (male, large size)]
	* [https://phantoms.martinos.org/DCA_voxels MGH "DCA" detailed voxel head model (female, medium size)]		* [https://phantoms.martinos.org/DCA_voxels MGH "DCA" detailed voxel head model (female, medium size)]
	* [https://phantoms.martinos.org/DBS Virtual Population]		* [https://phantoms.martinos.org/DBS_pop DBS Virtual Population]

	== 3D-printed phantoms construction tips ==		== 3D-printed phantoms construction tips ==

Guerin: /* MGH voxel numerical models for download */

2018-10-03T14:41:54Z

MGH voxel numerical models for download

← Older revision		Revision as of 10:41, 3 October 2018
Line 25:		Line 25:
	* [https://phantoms.martinos.org/HS6_voxels MGH "HS6" voxel head + chest model (male, large size)]		* [https://phantoms.martinos.org/HS6_voxels MGH "HS6" voxel head + chest model (male, large size)]
	* [https://phantoms.martinos.org/DCA_voxels MGH "DCA" detailed voxel head model (female, medium size)]		* [https://phantoms.martinos.org/DCA_voxels MGH "DCA" detailed voxel head model (female, medium size)]
			* [https://phantoms.martinos.org/DBS Virtual Population]

	== 3D-printed phantoms construction tips ==		== 3D-printed phantoms construction tips ==

Guerin: /* Filling */

2017-05-30T19:39:11Z

Filling

← Older revision		Revision as of 15:39, 30 May 2017
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	* Salt (NaCl): This is required for increasing the conductivity of the mixture and hence loading of the coil. See the graph on the right to determine the appropriate concentration.		* Salt (NaCl): This is required for increasing the conductivity of the mixture and hence loading of the coil. See the graph on the right to determine the appropriate concentration.
	* Sodium Azide (NaN3): 0.05%, this is used to prevent bacterial growth. (Use caution working with NaN3 as it is highly toxic. Do not let NaN3 solution contact skin. Also avoid exposing the powder or solution to metal objects, which can generate toxic gas)		* Sodium Azide (NaN3): 0.05%, this is used to prevent bacterial growth. (Use caution working with NaN3 as it is highly toxic. Do not let NaN3 solution contact skin. Also avoid exposing the powder or solution to metal objects, which can generate toxic gas)
	Additionally, one can add ethylene glycol ~~in powder~~ form to lower the permittivity (the mixture above has a permittivity close to that of water, i.e. ~80, which is greater than the permittivity of biological tissues, i.e. ~50). The proper concentration of ethylene glycol should be determined using a dielectric probe. In our experience, lowering the water permittivity to tissue-levels requires large amounts of ethylene glycol. This may change other parameters of the mixture such as its consistency and its conductivity.		Additionally, one can add ethylene glycol form to lower the permittivity (the mixture above has a permittivity close to that of water, i.e. ~80, which is greater than the permittivity of biological tissues, i.e. ~50). The proper concentration of ethylene glycol should be determined using a dielectric probe. In our experience, lowering the water permittivity to tissue-levels requires large amounts of ethylene glycol. This may change other parameters of the mixture such as its consistency and its conductivity.
	In order to prepare the mixture, we recommend the following step-by-step process:		In order to prepare the mixture, we recommend the following step-by-step process:
	* Heat the water in glass containers using a microwave oven until the water boils.		* Heat the water in glass containers using a microwave oven until the water boils.

Jaystock: /* 3D-printed phantoms construction tips */

2016-07-08T17:21:24Z

3D-printed phantoms construction tips

← Older revision		Revision as of 13:21, 8 July 2016
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	We have had success with the following aerosol spray rubber coating (3 or 4 coats):		We have had success with the following aerosol spray rubber coating (3 or 4 coats):

	Performix 11201 Plasti Dip Red Multi-Purpose Rubber Coating Aerosol - 11 oz.		Performix 11201 Plasti Dip Red Multi-Purpose Rubber Coating Aerosol - 11 oz. (Red)

	[http://www.mcmaster.com/#9560t4/=1370zq1 McMaster Carr weblink for Plasti-Dip rubber spray]		[http://www.mcmaster.com/#9560t4/=1370zq1 McMaster Carr weblink for Plasti-Dip rubber spray]

			The red spray works the best.

	=== Assembly ===		=== Assembly ===

Jaystock: /* 3D-printed phantoms construction tips */

2016-07-08T17:20:53Z

3D-printed phantoms construction tips

← Older revision		Revision as of 13:20, 8 July 2016
Line 45:		Line 45:

	Performix 11201 Plasti Dip Red Multi-Purpose Rubber Coating Aerosol - 11 oz.		Performix 11201 Plasti Dip Red Multi-Purpose Rubber Coating Aerosol - 11 oz.

	[http://www.mcmaster.com/#9560t4/=1370zq1 McMaster Carr weblink for Plasti-Dip rubber spray]		[http://www.mcmaster.com/#9560t4/=1370zq1 McMaster Carr weblink for Plasti-Dip rubber spray]

Jaystock: /* 3D-printed phantoms construction tips */

2016-07-08T17:20:43Z

3D-printed phantoms construction tips

← Older revision		Revision as of 13:20, 8 July 2016
Line 42:		Line 42:
	The next step is to seal the printed parts. Even if your 3D printer offers a "waterproof" printing option, in our experience this does not mean that the parts will actually be waterproof... 3D printing of waterproof parts is difficult. Mostly, the "waterproof" 3D printing options available on some printer work only for parts that are flat and don't have any complex details (e.g., flat panels). These almost always fail for complex geometries such as a human head. We have experimented with several techniques for waterproofing phantoms including painting the plastic parts with epoxy and melting of the plastic surface with a solvent (acetone can be used to melt ABS parts. Methylene chloride can be used to melt polycarbonate plastic). We have found that these two methods do not work well however. The method that we currently use for all our models at MGH consists in spraying the parts with a rubber spray. For our phantoms, we apply three thick coats of rubber spray on the outside and the inside of all parts (covering the outside of the outer parts prevents leaks and sweating in the event where some water infiltrates the plastic parts because of failure of the inner-most rubber coat). We use a red rubber spray as opposed to a black one since the latter color is often achieved using ferrite particles that may be magnetic. Note that the parts must be entirely sealed with spray before assembly (inside and outside surface), including the small grooves and nudges used for assembly of matching parts (for good mating of complementary parts after coating with the rubber spray, we have left some room between the matching grooves and nudges in the CAD models).		The next step is to seal the printed parts. Even if your 3D printer offers a "waterproof" printing option, in our experience this does not mean that the parts will actually be waterproof... 3D printing of waterproof parts is difficult. Mostly, the "waterproof" 3D printing options available on some printer work only for parts that are flat and don't have any complex details (e.g., flat panels). These almost always fail for complex geometries such as a human head. We have experimented with several techniques for waterproofing phantoms including painting the plastic parts with epoxy and melting of the plastic surface with a solvent (acetone can be used to melt ABS parts. Methylene chloride can be used to melt polycarbonate plastic). We have found that these two methods do not work well however. The method that we currently use for all our models at MGH consists in spraying the parts with a rubber spray. For our phantoms, we apply three thick coats of rubber spray on the outside and the inside of all parts (covering the outside of the outer parts prevents leaks and sweating in the event where some water infiltrates the plastic parts because of failure of the inner-most rubber coat). We use a red rubber spray as opposed to a black one since the latter color is often achieved using ferrite particles that may be magnetic. Note that the parts must be entirely sealed with spray before assembly (inside and outside surface), including the small grooves and nudges used for assembly of matching parts (for good mating of complementary parts after coating with the rubber spray, we have left some room between the matching grooves and nudges in the CAD models).

			We have had success with the following aerosol spray rubber coating (3 or 4 coats):

			Performix 11201 Plasti Dip Red Multi-Purpose Rubber Coating Aerosol - 11 oz.
	[http://www.mcmaster.com/#9560t4/=1370zq1 McMaster Carr weblink for Plasti-Dip rubber spray]		[http://www.mcmaster.com/#9560t4/=1370zq1 McMaster Carr weblink for Plasti-Dip rubber spray]

Jaystock: /* 3D-printed phantoms construction tips */

2016-07-08T17:19:32Z

3D-printed phantoms construction tips

← Older revision		Revision as of 13:19, 8 July 2016
Line 41:		Line 41:

	The next step is to seal the printed parts. Even if your 3D printer offers a "waterproof" printing option, in our experience this does not mean that the parts will actually be waterproof... 3D printing of waterproof parts is difficult. Mostly, the "waterproof" 3D printing options available on some printer work only for parts that are flat and don't have any complex details (e.g., flat panels). These almost always fail for complex geometries such as a human head. We have experimented with several techniques for waterproofing phantoms including painting the plastic parts with epoxy and melting of the plastic surface with a solvent (acetone can be used to melt ABS parts. Methylene chloride can be used to melt polycarbonate plastic). We have found that these two methods do not work well however. The method that we currently use for all our models at MGH consists in spraying the parts with a rubber spray. For our phantoms, we apply three thick coats of rubber spray on the outside and the inside of all parts (covering the outside of the outer parts prevents leaks and sweating in the event where some water infiltrates the plastic parts because of failure of the inner-most rubber coat). We use a red rubber spray as opposed to a black one since the latter color is often achieved using ferrite particles that may be magnetic. Note that the parts must be entirely sealed with spray before assembly (inside and outside surface), including the small grooves and nudges used for assembly of matching parts (for good mating of complementary parts after coating with the rubber spray, we have left some room between the matching grooves and nudges in the CAD models).		The next step is to seal the printed parts. Even if your 3D printer offers a "waterproof" printing option, in our experience this does not mean that the parts will actually be waterproof... 3D printing of waterproof parts is difficult. Mostly, the "waterproof" 3D printing options available on some printer work only for parts that are flat and don't have any complex details (e.g., flat panels). These almost always fail for complex geometries such as a human head. We have experimented with several techniques for waterproofing phantoms including painting the plastic parts with epoxy and melting of the plastic surface with a solvent (acetone can be used to melt ABS parts. Methylene chloride can be used to melt polycarbonate plastic). We have found that these two methods do not work well however. The method that we currently use for all our models at MGH consists in spraying the parts with a rubber spray. For our phantoms, we apply three thick coats of rubber spray on the outside and the inside of all parts (covering the outside of the outer parts prevents leaks and sweating in the event where some water infiltrates the plastic parts because of failure of the inner-most rubber coat). We use a red rubber spray as opposed to a black one since the latter color is often achieved using ferrite particles that may be magnetic. Note that the parts must be entirely sealed with spray before assembly (inside and outside surface), including the small grooves and nudges used for assembly of matching parts (for good mating of complementary parts after coating with the rubber spray, we have left some room between the matching grooves and nudges in the CAD models).


			[http://www.mcmaster.com/#9560t4/=1370zq1 McMaster Carr weblink for Plasti-Dip rubber spray]

	=== Assembly ===		=== Assembly ===