Ringbearer: Movable LED ring for 3D print lighting and analysis
Background
We would like to illuminate objects on our 3D printer bed, using an LED light ring, in a consistent and predictable way. This is specifically to enable the monitoring/examination of prints by a computer vision system, in real time. Due to the nature of computer vision analysis, best results are obtained in a well-lit, consistent environment, free of shadows. We would like to be able to change the height (Z) of this ring using stepper motors.
Objective
Design 3D printed apparatus to support a LED ring, and allow it to be moved up and down with stepper motors. Apparatus should minimize obstruction with normal operation of the printer.
Solution
Printed Components
Ringbearer consists of several pieces which are individually printed and then assembled. It's difficult to print a 1-piece object this large, so Ringbearer is composed of several component pieces:
| Quantity | Image | Name | Description | Plastic use |
|---|---|---|---|---|
| 6 | 
|
Sectional LED ring pieces | 6 of these in total are snapped together to form a plastic support ring, which allows the LED ring to be raised and lowered. The design is parametric, in OpenSCAD, to allow for different sized print beds, rings, etc. The module which draws the female threaded piece can be enabled or disabled, since only 2 of the 6 ring pieces will actually connect to a motor. Elevator rods screw into this piece, so the ring can be raised by the motor. | 6g |
| 2 | 
|
Elevator screw | This screw piece attaches directly to the stepper motor shaft. It threads into the elevator nut/ring holder and facilitates raising/lowering the entire assembly. | 7g |
| 2 | 
|
Motor Mounts | This mount attaches the NEMA17 motor to the side of the Athena printer. | 5g |
| Total: | ~ 60g | |||
| Plastic cost: | ~ $1.20 |
BOM / Non-Printed Components
These components are also needed in the Ringbearer design:
| Quantity | Name | Description | Unit cost |
|---|---|---|---|
| 2 | NEMA17 Stepped motors | These stepper motors attach to the elevator screw rods, and do the work for raising/lowering the LED ring | $13 |
| 8 | M3x ~5mm screws | Used to attach stepper motor to motor mount | $.01 (or scavenge from your local computer enthusiast) |
| 1 | Arduino | ...or other microcontroller capable of controlling the raising/lowering of LED ring as desired | $18.00 |
| 2 | Stepper motor driver | Used to easily drive stepper motor from microcontroller | $2.00 |
| Total | $48.08 |
Cost Analysis/Market comparison
No known existing product allows for the placement of a LED ring in the bed of a 3D printer, without interfering with printing operations, and allowing computer control of the LED ring height. With a total cost of $50 (potentially much less, for the scientist or hobbyist who has a suitable microcontroller/stepper motors on hand), this is an affordable method for getting started in computer vision analysis of prints.
STL / OpenSCAD files
Please find the latest STL, Parametric OpenSCAD files, etc in the NIH Repository.