Start with a challenge
A clear objective, real constraints, and measurable results. No prescribed solution.
Open engineering projects · Learn by doing
Real engineering.
Without the guesswork.
Engineering should be challenging. Learning how to engineer shouldn't be unnecessarily frustrating. Explore a real problem, learn what you need, and build your own solution.
How it works
The information is here. The engineering decisions are yours.
Learn what matters
Simple explanations first, with deeper technical references when you're ready.
Test your ideas
Measure, troubleshoot, revise, and discover why your design behaves as it does.
Project 001
The 50-foot challenge
Design a machine that launches a foam dart at least 50 feet. How you accomplish it is up to you.
See the project brief →Projects / Project 001
The challengeCan you launch a foam dart 50 feet?
Build a repeatable, controllable launching mechanism. You'll make decisions about mechanics, motors, power, control, and measurement.
Your objective
Design and test a device capable of launching a standard foam dart a horizontal distance of at least 50 feet under a repeatable test setup.
Prototype brief: exact dart specification and final test protocol are still being developed.
Where to begin
- Understand the energy required to move a dart.
- Compare possible launch mechanisms.
- Identify the variables you can control and measure.
- Build a prototype and test it safely.
- Improve your design based on evidence.
Safety comes first
Use eye protection, a controlled test area, appropriate electrical protection, and guards around rotating components. Never aim at people or animals. Safety requirements are not hidden behind hints.
Learning library
Start with the basicsLearn the parts you don't know yet.
No need to know the right terminology before you begin. Each topic starts with a simple explanation, then goes deeper.
Speed and energy
What's the difference between moving fast and having lots of energy?
Start learning →Motors and controllers
What makes a motor spin, and how do you control it?
Start learning →Measuring results
How do you know whether a change actually improved your design?
Start learning →Learning library / Mechanics
Understand the fundamentalsWhat does RPM actually tell you?
RPM tells you how many times something rotates in one minute. It doesn't tell you how fast the outside edge moves unless you also know its diameter.
Try it yourself
Move the sliders and watch how the surface speed changes.
Calculated edge speed
68.7 ft/s
Ideal geometric surface speed; this does not predict actual dart velocity or range.
Why it matters
A larger wheel travels farther along its circumference in one rotation. At the same RPM, its outer edge moves faster. Real performance also depends on load, friction, compression, and other losses.
← Back to learning libraryLearning library / Electronics
How does a brushless motor spin?
Electric current creates magnetic fields. A brushless motor changes those fields in sequence to pull its rotor around.
Start with the physical idea
Imagine moving a magnet around a circle just ahead of another magnet. The second magnet tries to follow. In a brushless motor, stationary coils create the moving magnetic pattern, and the rotor follows.
Go deeper: what does the ESC do?
The electronic speed controller switches current between motor windings in a timed sequence. It also manages how much electrical power is delivered.
Learning library / Testing
How do you know it got better?
A single successful launch isn't enough. Engineering requires repeatable measurements.
Try this
Keep the dart type, launch angle, and starting position consistent. Record several launches before and after a design change. Compare the average distance and the variation, not just the best result.
Project 001 / Workshop
Help when you need itStuck? Take one hint at a time.
Hints should help you think, not give away the solution. Open only as much guidance as you want.
Hint 1 — What's the first question?
What physical quantity does the dart need to gain before it can travel 50 feet?
Hint 2 — Think about energy
Compare the dart's kinetic energy at launch with the energy your mechanism can transfer to it.
Hint 3 — Make a measurement plan
Choose one variable to change at a time. Record distance, repeatability, and a relevant machine measurement such as rotational speed.
These hints are illustrative. Final challenge hints will be developed alongside testing and documentation.