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Primer

This is an open hardware project based on the Michael Peshkin Lightboard from Northwestern University:

https://sites.google.com/site/northwesternlightboard/

Concept

A simple design that allows a lecturer presenting to a camera to write as they would on a white board but facing students.  This eliminates the need for complicated computer generated graphics. 

Differences between the Duke Lightboard and the original Peshkin Lightboard

The Duke Lightboard focuses on smaller, lighter construction the goal of eliminating the need for many studio accessories.  As a result, the design is somewhat portable and reduces the need for complicated lighting arrangements.  The three key technical elements are the use of an electronic "flipper" to mirror the video, the use of a custom designed LED clip, and the exclusive use of bolt-together 80/20 aluminum framing as opposed to a welded steel frame.  A project goal is also to create a design that is simple enough a lower level technician could build it.  It was also desirable to use common, easily sourced components for the construction.

The electronic flipper processes the reversed image as opposed to shooting the camera through an actual physical mirror as spec'ed in the original design.  This eliminates complication and geometry from the design as well as increasing the light input to the camera.  The LED Clip is also a key element.  The design holds cheap 3528 sized LED's on standard 8mm strips precisely up to the glass.  The design is extremely light and includes framing for a second LED strip that can illuminate the face of the lecturer without the need for industrial studio lighting.  The second Subject LED Strip is set to a warm 3000K temperature which is more appropriate for human skin.  The clip can be reproduced using simple extruding or 3D printing technologies.  The use of 80/20 components considerably reduces the weight of the final product while making it easier for someone who does not have access to a welder or other metal working equipment.

Design Evolution

The project progressed through two stages where a small prototype was built to test various concepts while providing an example instructional development teams could use in designing course concepts and material.

Prototype

Bill of Goods for Prototype (3'x2') Lightboard

Bill of Goods for Desktop (6'x4') Lightboard

Studio Lightboard Construction

80/20 Primer

This version of the Lightboard makes heavy use of 80/20 T-Slot extruded aluminum.  T-Slot uses special nuts slid into slots then tightened to make a joint.  Joint pieces come in a variety of shapes and sizes for various applications but the concept is the same.  The special nuts (called T nuts) in this project are either single, double, or triple length.  Note that using double and triple T-nuts where possible makes construction easier.  An example is demonstrated in the video below.

80:20.m4v

LED Clip Primer

This project uses specialized clips to hold the LED strips precisely to the glass and provide subject lighting for the presenting lecturer.  The clips are easily manufactured with 3D printing. The LED strips must then be inserted into the LED clip.  This is demonstrated in the video below.

LED Clip.m4v

Principle Construction

Instructions	Diagram	Example Photo	Example Photo
Construct left and right side frame by joining 1x 72" 80/20 extrusion to 1x 80/20 24" extrusion with a 5-hole T-Joining Plate, build two of these T shaped structures
Add supports for left side of frame by joining 1x 45 degree 15 series support to the T shaped structure created in step 1.  The 45 degree supports have their own joints built in
Add 5 hole corner bracket to what will be the back side of the left and right frame
Add rear bracing by first taping the bottom 24" 80/20 1515 section.  Add a pivot nub to
Add 5 hole T-Joining plate to the bottom of the frame at the same location as the vertical 72" piece of 80/20 1515
Add corner gusset to the middle and top of the frame near the centerline of the holes you had cut in the glass.  Subtract 3/4" for the center line of the 80/20 1515 crossbar we will be adding.
With both the left and right side of the stand complete, join them together at the bottom with two pieces of 72" 80/20 1515 acting as crossbars.
Attach 2x 45 degree 18" or 12" supports to the inside of the two frames and against the bottom, center crossbar.
Insert 4x 5/16 T-Nuts into the remaining 2 72" 80/20 1515 crossbars, latter these will support the glass.  With the side containing the T-nuts facing forward, mounting them as cross bars to the structure.

Schematic For Studio Lightboard Glass

Studio Lightboard Power Consumption

Cleaning Methodology

• Wipe Lightboard clean with a traditional whiteboard eraser
• White residual power from Lightboard with a clean, dry paper towel
• Use a thin mixture of Dawn dish detergent in a spray bottle and mist the surface of the glass
• Use a squeegee to wipe the cleaner off