Want to make your LEGO Spike Prime robot turn perfectly every time? Whether you're preparing for FIRST LEGO League or just want to build better bots, this step-by-step guide will help you fine-tune your robot’s turning using real data and the built-in Yaw sensor.
🔍 What You’ll Learn
- What a Yaw sensor is and how it works
- How to apply the Scientific Method to robot programming
- Why robots overshoot turn angles at higher power levels
- How to calculate and apply a correction offset
- How to build smarter, more reliable turning code using My Blocks
🎥 Watch the Full Tutorial
🧭 What Is Yaw and Why Does It Matter?
Yaw measures your robot's rotation around the vertical axis—basically, how much it's turned left or right. The LEGO Spike Prime Hub tracks yaw from -180° to 179°, making it perfect for turn-based navigation.
But there's a catch: as motor power increases, so does inertia—which means your robot often overshoots the desired angle.
🔬 The Scientific Method for Better Turns
Here’s how we used the Scientific Method:
- Ask a Question: Why does our robot overshoot 90° turns at higher power?
- Form a Hypothesis: Higher power = more overshoot.
- Conduct an Experiment:
- Turn to 90° using different power levels (20%, 30%, 40%, 50%)
- Run 5+ trials at each level
- Record the actual stopping angle
- Analyze Results:
- Calculate average overshoot
- Determine offset needed for accuracy
- Apply & Test:
- Modify your code to stop before the target angle
- Improve My Block logic to factor in speed-based offset
📊 Example Data Table
| Power % | Target Angle | Actual Avg. Angle | Offset Required |
|---|---|---|---|
| 20% | 90° | 92° | -2° |
| 40% | 90° | 97° | -7° |
| 50% | 90° | 100° | -10° |
Use this data to adjust your wait-until yaw angle block by subtracting the correct offset.
This is the code we will be modifying for the experiment.
🧱 Build a Smarter My Block
Create a custom My Block called YawTurn. It should:
- Take input: angle,
- Reset yaw
- Estimate the offset based on power
- Subtract offset from target angle
- Wait until yaw = corrected angle
This makes your robot modular, reusable, and competition-ready.
✅ Why This Works for FLL and Classroom Robots
By controlling your turns with this method:
- You’ll score higher in the Robot Game
- Your robot will navigate missions with confidence
- You’ll teach students real scientific inquiry through robotics
📥 Get the Lesson PDF + Sample Code
Download:
🔑 Learning Targets
- How to improve LEGO Spike Prime robot turns
- LEGO Spike Prime turn accuracy
- Use yaw sensor LEGO robot
- FLL robot turn programming
- Yaw offset LEGO robotics
💬 Leave a Comment or Question
Have questions about your robot's turns? Drop them in the YouTube comments or email us directly!
About Preston Spratt your Robotics Instructor
Preston Spratt started Sprattronics to provide children with incredible learning opportunities. As a school principal, he has specialized in bringing project-based learning into schools. Sprattronics is a place for children to learn about the things that interest them and solve problems that excite them.
Parents should have a choice of what their children are learning, and that it can happen in a safe and welcoming environment. At Sprattronics, Greenville, South Carolina, we focus on children making discoveries and encourage them to explore the things that interest them.