Video Link: click
Autodesk Inventor Software
Ultimaker 2 3D Printer / PLA Plastic Filament
Servo Motor / Gear
Toggle Switch for Motor
Slide Switch for Circuit
15 Blue LEDs
Soldering Iron / Solder
3V Battery / Holder
Fire, steam, chemicals, and currents - these are just four causes of burns that people encounter several times on a daily basis. The number of burn victims in the United States every year is 486,000, and of those up to 10,000 die every year (Burn, 2008). Furthermore, a prevalent condition following those injuries is the infection of burn wounds; 61% of the deaths related to burns (6100 deaths) (Fonseca, 2009) are directly caused by infection. To aid in lowering the number of these deaths, a research idea of creating a mechanized approach to protecting the skin immediately after it is burned was developed. By applying ultraviolet (UV) light to skin quickly after it is burned, infection and therefore more serious conditions such as psoriasis can be extirpated before they make a presence. The period after one has been burned is critical - the skin is open and if not treated properly, chances of infection rise greatly. In creating a mechanism to apply staggered UV lighting, patients can receive helpful and more effective therapy before they reach the hospital where they can be fully treated. The mechanism will function by enveloping a limb or extremity and providing controlled amounts of UV therapy, which has been shown to be effective in preventing burn wounds from becoming infected (Aleem, 2013). This research will have a positive impact on society due to its ability to reduce the amount of time, money, and trauma put into burn wounds every year.
Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.
Step 1: Design the Inner Ring
The first step in creating this device is to design an inner ring. The method used for the creation of the inner ring was 3D printing, but alternate methods can also be utilized to create such a part. As shown in the image provided, the holes have rotational symmetry and are a constantly repeating pattern to ensure the lighting's intensity is constant over time. To design the ring, you may use any 3D design software. The ring has an end with a significant distance jutting out - this will help it stay mounted in the bigger ring. Beyond the edge, the ring also has a large gear with a design that allows it to fit in with the existing gear you have identified for use in the part. This gear will create the spinning mechanism needed by the device.
Step 2: Design the Outer Ring
The outer ring is where things become more challenging. To successfully create your outer ring, you will need to dimension its opening to create a fit tight enough for the inner ring slide. This can be done by creating a .005 in difference in the radii of the rings as a tolerance. Furthermore, to add a motor to drive the inner ring's rotation, a space for the motor to rest is required. Finally, a lid is required to create an opening for maintenance of the device. In the lid, the LEDs will be added for the UV therapy. Holes can be added to the CAD model for the LEDs, or as an alternative they can be drilled by hand after printing is complete. Furthermore, a hinge is required to allow the lid to stay attached but still rotate open and closed in a door-like manner.
Step 3: LED Circuit Setup
Using a 3V battery / holder, a soldering iron, solder, jumper wires, and the LEDs, create a parallel circuit with equal amounts of LEDs on each branch to maintain constant light intensity. Attach the power supply and secure LEDs with hot glue if required.
Step 4: Motor Set Up
In this prototype, a servo motor was used along with an Adafruit micro controller. The attached code is used in the micro controller to drive the inner ring's rotational motion. A toggle switch is used to turn on the motor and begin the motion. The motor is attached through the switch to the board and receives power from the board as well as from an external 3.5 V outlet supply.