Introduction: 3D Printed Dissection Model - Earthworm

The Problem:

The problem that I am investigating is the dissection of animals. Approximately 10 million animals are killed every year for dissection in the United States alone. Animals are taken from their natural habitats and are killed for my learning. Many students don’t like to dissect animals because of religious reasons or simply because dissecting animals leaves them traumatized. This also causes many students to veer away from pursuing a job in the sciences. Storing these animals also requires the use of preservatives such as formaldehyde which is a cancer causing chemical. Online dissections do not have the same effect as doing a dissection by hand. They do not provide the same 3D experience as a real dissection and do not allow textures to be observed.

I researched on the structure of the anatomy of an earthworm and began to design it Autodesk Fusion 360. I consulted a few experts before making the final decision to print our first prototype. After this I did several prints to further refine our model, slowly improving all the small aspects of the earthworm.

The Solution:
Since most dissection animals are costly and most students don’t like doing dissection, I created a solution where the model will be both cost effective and students will feel comfortable doing it. The solution is a 3D printed model of an animal that has a replicated anatomy with an accurate design. I designed our model using Fusion 360 and printed it using a filament called the NinjaFlex. The NinjaFlex is a flexible filament similar to a rubber band that can be cut through or manipulated in the way that you would to a dissected animal. For my first prototype, I have 3D printed an earthworm with the same texture as an actual earthworm. I printed this model using the Lulzbot Mini 3D Printer. With this technology, I can continue to design new animal anatomy and 3D Print them in a similar fashion. My next step would be to print a rat because of its more frequented use in science classes in high school.

I approached my research in a systematic process where we began with identifying the problem and then discovering an innovative solution to the problem. I researched different ideas based on the problem of animals being killed for high school dissection. After research from different sources, I found that 3D Printed Dissections was not a common idea and that it would be a unique project if I was able to execute it properly. I began to slowly contact experts and they shared their opinion on my idea and what they thought could be improved on or researched on more extensively so that we can justify our points.


3D Printers are slowly becoming more widely available in schools. The filament used to create this model is also available from order online on their website at any time. The software required to design these models are also free. The cost of printing one of my worms are about 2 dollars but can vary based on the accuracy and precision of the print. These model take about 30 minutes to an hour to print so are not too time-consuming. This makes these models ideal for a school environment where both the cost and time for printing these models aren’t too much. Prints can be run on their own and do not require any interference. As this method becomes more widespread, schools will invest on more 3D Printers so that the prints can run quicker and so that it is not as time-consuming. Also, with more powerful 3D Printers, the prints would run faster and would have more precision and accuracy compared to our current model.

Step 1: Creating Overall Body Structure of the Worm

Draw the shape of the body of the worm using the sketch tool. Use the fillet to create the curved edges.

Step 2: Creating the Circulatory System of the Worm

Use the Extrude Function on the Sketch to make it 3D. Then, sketch the circulatory system. Use the fillets to create the curved edges. You can also use the 3 point Arc function to create the curved edges.

Step 3: Putting Together Both Structures

Use the Extrude Function to change the sketch to a 3D Object. Then use the move tool to move both the Body Structure and the Circulatory System together. Make sure the Body looks like it is floating inside the Circulatory System. Also, make sure the Body is attached in some way to the Circulatory System

Step 4: Creating the Nervous System of the Worm

Draw the Nervous System using the Sketch Function. Once you are finished, use the Extrude Function convert the sketch from 2D to 3D.

Step 5: Putting Together the Body, Circulatory System and Nervous System of the Worm

Use the Move Function to put the Nervous System in between both the Body and the Circulatory system, but make sure the brain of the worm can be seen from both sides of the worm.

Step 6: Creating Digestive System of the Worm

Use the Sketch Function to draw the Digestive System of the Worm. Make the curved edges using the fillet. If you want the system to be as precise as possible, you can zoom in and add more detail. Use the Extrude Tool to convert the object from 2D to 3D. Then put the Digestive System on the back of the worm and make sure a part of it is outside the body.

Step 7: Creating Veins and Smaller Parts of the Worm

Zoom in and use the Sketch Function to create small veins that will be attached to the nervous system. Use the Extrude Function. Move the Veins onto the nervous system so that they are completely on top of the body. Make sure the veins are connected to the nervous system

Step 8: Converting to T-Spline and Making Worm More Realistic

Convert the B-Rep object to T-Spline. Play around with the different functions in the Sculpt mode and see what way you think the internal part of the worm will look best. This step is mostly for making the worm realistic and creating more detail.

Step 9: Creating Outer Layer (Skin) of the Worm. (Printed Model)

Use the Toruses in the Modelling mode to create the Outer Layer. Duplicate the Toruses till you have enough to create the skin. Use the Combine Function to combine all the Toruses. The amount of Toruses is based on how much detail you want. (Make the Toruses wide making sure that they don't touch the inside of the worm)

Step 10: Adding Both Ends of the Worm to Complete the Dissection Model

Use the T-Spline Sphere for the two ends of the worms. Cut both spheres in half and resize them according to the size of your toruses. Attach both hemispheres to either end of the worm. Convert all parts to mesh. Merge all parts and make them all one object.

Step 11: You Are Now Finished Creating Your Own 3D Printed Dissection Model of an Earthworm!

Fusion 360 Archive files are included in each step showing the end product. Use the Upload function on Fusion 360 to be able to view these files. Make sure to print with supports! Enjoy!

Design Now: 3D Design Contest 2016

Participated in the
Design Now: 3D Design Contest 2016