3D Printable Grip and Lens Cover for ASUS XTION Handheld 3D Scanner

A 3D printable grip and lens cover for the ASUS XTION motion sensing hardware which is very affordable and popularly used as a hand-held 3D scanner.

The XTION normally stands on a base for table-top use which is not aimed to be hand-held. This 3D printable file was designed to fit the ASUS XTION making 3D scanning much easier and the device more comfortable to use.

This article also covers the basic steps on how to 3D scan a human body and finalise the mesh in Autodesk MeshMixer.

Step 1: Download the Free 3D Files

Download the 3D model of the grip and lens cap from the link below. Both parts are placed side-by-side ready to be 3D printed.

https://www.123dapp.com/smb-123D_Design/ASUS-XTION-3D-scanner-grip-and-lens-cover/2001332

Step 2: 3D Print the Grip and Lens Cover

Import the STL file in the 3D printers software and make sure to place it inside the build volume. This grip and lens cap must be durable, use at least 2 or more shells (perimeters) and 30% infill or more.

When the 3D print is done, remove the parts carefully from the build platform. In most cases wedging a sharp strait painters spatula between the bottom of the 3D printed part and the build surface, releases the objets nicely.

Step 3: Attach the Grip to the ASUS XTION

Unscrew the original table-top stand from the ASUS XTION and replace it with the 3D printed grip. Note the following steps.

- Do not over-tighten the screw!
- The furrow points backward away from the lenses
- Insert the USB cord into the furrow

Step 4: Insert the USB Cable and Ferrite Core

Make sure the ferrite core of the USB cable fits completely into the grip's cavity. Secure it in place by cutting a 36 mm long piece of 1.75 mm 3D print filament from your 3D printer's material spool. Push the cord into the cavity and insert the filament strip sideways.

Step 5: Secure the Bottom Part of the USB Cable to the Handle Base

Push the USB cable into the furrow and secure it with a 26 mm long piece of 1.75 mm 3D print filament. Note that the cord exits the grip backward which keeps it away from the front of the grip where the 3D scanning occurs.

Step 6: Bottom Part Attaches to Flat Surfaces

Note that there is an array of holes on the flat bottom of the grip. This makes it easy to screw it onto flat surfaces or for instance camera tripods, etc.

Download the DXF-file as a drill template. Print it on paper and glue it to the surface you want to drill holes into.

ASUS XTION 3D scanner grip (fixture template).dxf
Download

Step 7: Place It Upright on a Table

The flat bottom part of the grip makes it possible to place the XTION upright on a flat surface.

Step 8: Protect the Optics!

Snap the lens cover over the optics of the XTION device when not in use. Note that this cover can be reversed and snapped to the back part of the scanner. This keeps the cover always together with the XTION so that it won't be lost.

If this this still happens or for instance the covers flexible legs break for some reason, just 3D print a new one! :)

Step 9: Stows Away Nicely

The flat bottom of the grip and the legs of the cap makes it easy to wrap around the USB cable and make it tidy when the XTION is not in use. We recommend a USB extension cord when 3D scanning.

Step 10: How to 3D Scan a Human Body

The next few steps give a short explanation on how to 3D scan a human body with an ASUS XTION handheld 3D scanner.

Start a 3D scanning software on your computer. Below are a few compatible with the XTION, Kinect and other PrimeSense-enabled hardware devices.

Step 11: Start the 3D Scan and Export to STL

Refer to your software's user interface and settings to achieve the preferred scanning distance. Since most of these softwares use realtime tracking and global registration, we recommend that you start your 3D scan from the front of the person you are scanning. This will make it easier for the software to create a coherent mesh when you have circumvented the body.

Once you have finished the 3D scan, export the file as STL format. This will then be able be imported into a 3D print mesh healing software such as Autodesk MeshMixer. 3D scanning softwares usually have mesh fixing features which can be valuable to make a water-tight mesh, but i most cases further adaptation of the result is necessary and therefore a software with more advanced features is preferred.

Step 12: Prepare the 3D Scanned Mesh for 3D Printing

Normally a 3D scanned mesh has many separated parts. One only needs the main surface and therefore the minor insignificant mesh islands need to be removed. In MeshMixer this as follows:

- Import your 3D scanned mesh
- Press S to start selection mode
- Click once on the main mesh to select a small part
- Press E to expand this selection to all connected triangles
- Press I to invert the selection
- Now all eventual small islands are selected
- Press X to delete them
- Save your MeshMixer project file!

Step 13: Turn the Model Upright

Now you need rotate and move your scan as follows:

- Press T to start transforming your object
- Grab the rotate gizmo and orient your model as you desire
- Press Accept to finalise the transformation

Note that you can also move your model to a centered position in this same step by grabbing the arrows of the gizmo.

Step 14: Rough-cut Away the Bottom Part of the Mesh

Now you need to cut away most of what you don't want from the bottom part of your model.
- Choose Edit > Plane Cut
- Use the rotation and placement gizmos for the cut plane
- Note that the transparent part of the model is deleted in this step
- Press the small blue arrow to reverse the direction of the cut
- Press Accept to cut-away the lower part of the mesh

Step 15: Inspect the Model for Holes and Defects

Now you have to find out where holes and other defect parts of your mesh are.

- Choose Analysis > Inspector
- Lots of needle-shaped pointers appear
- Press the ones that you find fix most issues
- Do not press the needle indicating the lower big cut hole. Leave that for later.
- If a cut does not work the needle turns black. Just ignore those and keep fixing others.
- When most or all (except the cut hole) are finished, press Done.
- Repeat this step several times if necessary.

(Probably you will be thinking of voodoo dolls now! :)

Step 16: Manual Mending of Holes

In some cases the mesh shape is too complex for MeshMixer to understand what has to be done to fix it. A human brain (yours!) needs to do that. ;)

Rotate the view and look at your model to find obvious parts to fix manually. In most cases it is easy to select the bad part and delete it to create a hole. This removes the unwanted surfaces and the hole can be filled instead. There is a tool in MeshMixer that does this in one step.

- Press S to select and paint a part of the mesh (for instance surface spike or the area surrounding a hole)
- Press F
- See the MeshMixer magic happen!

To further learn about how to use MeshMixer, we recommend the following video tutorials.

http://www.youtube.com/user/meshmixer/videos

Step 17: Make the Final Cut for the Bottom Part of the Model

Before you can cut the bottom part of the model and create a flat surface you need to have a continuous strip of mesh. In some cases the bottom contour of the mesh has bay-shaped holes. To fix them just use the Move Sculpt brush (make it very large) and "drag down" the bight so that it protrudes below your new cutting plane.

- Choose Edit > Plane Cut
- Place the plane where you want to cut
- Make sure to select Hard Edge
- Press Accept to create a cut and also make a solid flat plate on the bottom of the part.

The original raw 3D scanned mesh, as well as the MeshMixer project file and the final STL for 3D print can all be downloaded below.

Step 18: Analyse the 3D Model for 3D Print Overhangs

In most 3D printing processes, parts of the model which have overhang need to be supported with some kind of structure.

3D print software usually takes care of this nicely but it is always great to have perfect manual control of where the support structures are placed. MeshMixer has powerful features to help you do this such as follows:

- Choose Analysis > Overhangs
- You can now see a red colour on the overhang parts of your model
- Press Support All Overhangs to create support structures automatically
- Hold down cmd/ctrl and left-click on the structures you want to remove
- Hold down Shift and left-click-and-drag on parts where you want to create new structures.

For a rough overview of how this model was fixed please see the video below.
- http://youtu.be/wsq8C5jMgqc