Using the FologramQR command to create placement markers

Fologram allows you to precisely place your digital models in 3d space using 3 simple steps.

  1. Specify a set out point in Rhino and save it as a QR code.
  2. Print the QR code and fix it at the physical set out point.
  3. Snap the digital model to the QR code in Fologram.

Depending on your use case, you may want to carefully consider an appropriate set out point, whether to roughly place your model and then modify the Rhino model after placement to make minute adjustments for fabrication, or place models with multiple codes when working in large spaces.

Creating a position QR code


Use the FologramQR Command to specify where your code will be located relative to the origin of your model. Specifying 0,0,0 as the position for the code is a good way to quickly set the origin. You can also set the orientation of your code if you are planning on fixing the code to a horizontal or vertical surface.

Using a QR code to align your model to a construction site or existing building

Create a QR code at a known reference point in your digital model. A good place to create the code is in the corner between two existing walls, the corner of a slab, or at an exact distance along an existing edge of a wall or slab. The position of the QR code is in the bottom left corner of the code, so be careful to account for the width of the code and the printed paper when setting the code position. Print off the code and place it in the correct physical location. Place your model on the image target by selecting the Snap to Marker tool from the menu, then look at your code until Fologram reports that the model has been placed on the marker.

Using multiple codes to correct for rotational error

Placement with a single code can introduce significant rotational error with large holograms due to limitations in the HoloLens or mobile camera in detecting the code orientation. This can be overcome by placing a second code on site. After placing the first marker, use the Snap to Marker tool to snap to the second code. Fologram will automatically interpolate between tracked code positions and correct for any rotational error.

Using a QR code to align your model to a workbench

Create a QR code at the origin of your Rhino model. Print off this code and tape it to the corner of your work bench and connect Fologram to Rhino. Place your model on the image target by selecting the Snap to Marker tool from the menu, then look at your code until Fologram reports that the model has been placed on the marker. Now you have your origin snapped precisely to your code, you can re-position your Rhino model until it is in the desired location on your workbench. Note that this is easiest if you wear the HoloLens while also moving your model in Rhino. If you are working with very simple geometry you may also be able to simply grab and move the hologram of your model to the desired location.

Precise alignment of a hologram with a physical tool using Grasshopper

The process forprecisely aligning a part with a tool (such as a drill press, bar bender etc) can be exactly the same as the steps described above. You can use Grasshopper to build a mixed reality interface for making very fine adjustments to model position and rotation without needing to move the model around in Rhino. For instance, create a Move component with a VectorXYZ input, and synchronize three sliders connecting to each of the vector x,y and z components. Use a synchronize object component to stream the moved geometry to Fologram. Then adjust these slider values using the Parameters panel in Fologram - no need for rhino.

Regarding multiple QR codes:
when working on a big model (10-20 meters) can I have more than 2 QR codes to correct for rotational error and digital drift? Should these QR codes each be unique? As you describe above with 2 QR codes… we place an initial QR code then snap the model to the second QR code or does the model stay with its origin at the first QR code… Is it possible to put QR codes on the wall as well? Does Fologram dynamically track them of just once upon snap? Hoping to learn to increase the accuracy on architectural scale constructions. Thanks for all your advice!

Hey Ethan,

We’ve already discussed this offline, but I’ve created a post that outlines the process using multiple placement markers in Fologram here.