This week focuses on modeling experimental objects and parts of my final project using 2D and 3D software, demonstrating various design processes, and learning proper file compression techniques.
Assignment Requirements
Task: Computer-Aided Design
Objective: Model (raster, vector, 2D, 3D, render, animate, simulate, …) a possible final project, compress your images and videos, and post a description with your design files on your class page.
Final Project Modeling: Pulse Jet Engine
For this week's assignment, I used my pulse jet engine concept from Week 1 as a test subject to explore different CAD and modeling software tools. This allowed me to evaluate various software options that I might use for my final project.
Design Approach
The software testing focused on:
Parametric 3D Modeling: Testing precision and dimensional control in different CAD packages
Organic Modeling: Exploring sculpting and artistic modeling capabilities
AI-Powered Generation: Experimenting with text-to-3D model creation
Physics Simulation: Testing animation and simulation capabilities
Software Testing and Evaluation
I tested multiple software packages for modeling, exploring both traditional CAD tools, web-based platforms, and AI-powered solutions. Each software was evaluated for its strengths, weaknesses, and suitability for different types of design work.
Primary Choice - My go-to software with extensive experience for parametric 3D modeling and engineering design.
Pulse Jet Engine Design Process
Using Fusion 360, I designed a Lockwood-Hiller inspired valveless pulse jet engine. The design uses 18-gauge stainless steel (0.0500 inches / 1.27 mm thickness) for most components and 16-gauge stainless steel (0.0625 inches / 1.59 mm thickness) for the combustion chamber due to higher heat exposure.
Started by drawing a 3-inch diameter circle 2 inches away from the origin using the sketch tool.
Used the revolve tool to revolve the circle 180 degrees around the z-axis, creating the characteristic U-shaped bend.
Created a plane on the bend face and offset an inner circle by 0.0500 inches (18-gauge thickness), then used revolve tool set to cut to make the tube hollow.
Offset a plane 14 inches from the upper circle and created a 2.5-inch diameter circle for the transition cone.
Used the loft tool to connect the 3-inch upper tube to the 2.5-inch circle, creating a smooth transition.
Created inner circle offset by 0.0500 inches and used loft tool set to cut to hollow out the cone section.
Offset plane by 1 inch and created 5-inch diameter circle for combustion chamber expansion using loft tool.
For the combustion chamber, used 16-gauge steel (0.0625 inches offset) due to higher heat exposure, then extruded 12 inches for total chamber length.
Created transition from 5-inch combustion chamber to 3.5-inch intake/outlet using the same loft technique, then extruded 12-inch long pipe.
Started lower exhaust section by offsetting plane 57.750 inches and drawing 6-inch diameter circle with 0.05-inch wall thickness (18-gauge).
Added final cone section offset by 1 inch, expanding to 5-inch diameter to complete the basic pulse jet concept. Fuel injection system will be added later.
New Experience - Completely new to me, exploring animation and physics simulation capabilities.
Cloth Physics Simulation
Created a cloth physics simulation to test Blender's animation and physics tools:
Created a mesh sphere to act as the ground/collision object.
Added a plane, scaled it up, and moved it above the sphere. In Edit Mode, subdivided the plane 30-100 times to allow realistic deformation.
Added "Collision" physics to the sphere and "Cloth" properties to the plane in the Physics tab.
Pressed play to watch the cloth simulation interact with the collision object, demonstrating Blender's physics capabilities.
Simulation Video
Full cloth physics simulation showing realistic fabric behavior and collision detection.
Web-Based Tool - Online sculpting software that models like sculpting clay.
Face Sculpting Project
I created a face model using SculptGL to test its sculpting capabilities. This software was difficult to use for making precise geometric shapes - the clay-like modeling approach made it challenging to create square shapes and maintain dimensional accuracy.
SculptGL interface showing the sculpting process and tools available.
Final face model created using SculptGL's clay-like sculpting tools.
AI Platform - Web-based AI-powered 3D modeling platform that turns text prompts into 3D models supposedly in under a minute.
AI 3D Generation Tests
I created an account and was given 300 credits to test this AI technology. I've never tested an AI that can do this sort of stuff before. The website is clean, easy to navigate, and shows examples of previously made models, including some that have been 3D printed.
Test 1: 1979 Ford Bronco
Prompt: "Create a model of a 1979 Ford Bronco"
Time: 1:38.88 (not quite under a minute but still wicked quick)
Credits Used: 20
Result: Pretty good overall. You definitely would need some refining details if you wanted to 3D print, but for the speed, it's impressive.
Test 2: Bronco Keychain
Prompt: "Create a simple 3D model of the front face of a 1979 Ford Bronco designed as a keychain. Focus only on the front view (grille, headlights, hood, bumper), with no full vehicle body."
Time: 2:31.93 (took a little longer, which is interesting)
Result: Didn't really understand the prompt - created another full truck model instead of just the front face. The design wasn't consistent with the original truck but showed less stringiness and was cleaner overall. It mixed different Bronco generations: the '78-'79 (2nd gen) with later versions like the '80-'86 (3rd gen) and maybe a bit of the '87-'91 (4th gen), which is weird.
Interesting Detail: The AI added some weird mechanics on the underside, including what looks like some sort of dual rear differential. I can't blame it though - this is a pretty complex design it chose to make, and in the amount of time it did it, it's pretty well done.
Conclusion: The one problem is on the free model of this software you can only download models made by Meshy 4 - only 10 per month - but you can still generate with the other models. It feels like a waste and is probably designed to get people hooked, then at the end of the process they find out they can't download their model. That said, it was cool to see where this technology is going and how fast it's developing and getting better. I don't see the use of it for anything with specific dimensions, but I'm sure you could probably get it pretty close by scaling it in a slicer if you're planning on 3D printing. I think it's more developed for art and making 3D characters - if that's what you're interested in, I would definitely recommend you try it out.
Web-Based Software - Free web-based software that can be used for both 2D and 3D modeling, though it excels more at 2D modeling.
Table Design Project
I designed a table using SketchUp's free web-based software. You can access it at sketchup.trimble.com - just click "Start Modeling" and create an account (which you have to do).
Table design created in SketchUp. It's not the best, but it took me some time to understand and learn the controls.
SketchUp Experience
I actually liked using SketchUp - it's quite similar to Fusion 360 in some ways. While I would prefer to do my 2D designs in Fusion, I really liked this software. The only things are it didn't have many ways to edit like adding arcs or fillets to corners, it was harder to set measurements, and I couldn't get it to change from cm to inches even though I selected the setting and saved it. The camera slips a lot while working which is really annoying. If you want to change a dimension later, you often have to remodel the object rather than simply editing a parameter, which is also annoying. The midpoint selection is also buggy - when you select the midpoint of a line, sometimes it doesn't actually select the exact point, and this happens often.
Image Compression Demonstration
TinyPNG Compression Results
For all screenshots and documentation images in this assignment, I used TinyPNG to compress the file sizes while maintaining visual quality. This significantly reduces page load times and bandwidth usage.
Quality: Lossless compression for technical drawings
Design Files Repository
File Organization
All original design files are organized and available for download:
3D Models
📦 Pulse Jet Engine VX2 Native Fusion 360 file with complete parametric model Download .f3d file
Documentation
📸 Process Screenshots 11 step-by-step images documenting the Fusion 360 modeling process (PNG format, compressed with TinyPNG)
🎬 Blender Simulation Video Cloth physics simulation demonstration (MP4 format, 360KB)
🖼️ Software Testing Images Screenshots from SculptGL, Meshy.ai, and SketchUp testing (PNG format, compressed)
File Formats
Available: .f3d (Fusion 360 native), .png (images), .mp4 (video) Note: Universal formats (.step, .iges) and additional exports can be generated from the .f3d file as needed.