---

title: Differential Drive Turn Simulator description: Type: MicroSim sim-id: differential-drive-simulator
Library: p5.js
Status: Specified Create a p5.js MicroSim with a 700 × 450 canvas. image: /sims/differential-drive-simulator/differential-drive-simulator.png og:image: /sims/differential-drive-simulator/differential-drive-simulator.png twitter:image: /sims/differential-drive-simulator/differential-drive-simulator.png social: cards: false status: implemented library: p5.js bloom_level: TBD

---

Differential Drive Turn Simulator

Run the Differential Drive Turn Simulator MicroSim Fullscreen

About this MicroSim

Type: MicroSim sim-id: differential-drive-simulator
Library: p5.js
Status: Specified Create a p5.js MicroSim with a 700 × 450 canvas.

Bloom's Taxonomy level: TBD

You can embed this MicroSim in your own course page with the following iframe:

<iframe src="https://dmccreary.github.io/stem-robots/sims/differential-drive-simulator/main.html" width="100%" height="452" scrolling="no"></iframe>

Lesson Plan

Learning objective: Type: MicroSim sim-id: differential-drive-simulator
Library: p5.js
Status: Specified Create a p5.js MicroSim with a 700 × 450 canvas.

Suggested use (5-15 minutes):

1. Predict first. Before touching the controls, ask students to predict what they expect to see.
2. Explore. Have students interact with every control and observe how the display responds.
3. Explain. Ask students to describe, in their own words, the relationship the MicroSim demonstrates.

Discussion questions:

• What changed on screen when you interacted with the MicroSim, and why?
• How does this idea show up when you program the real robot?

References

• Chapter 7: PWM, Motor Speed Control, and Actuators
• Differential wheeled robot (Wikipedia)
• Dead reckoning (Wikipedia)

Specification

The full specification below is extracted from Chapter 7: PWM, Motor Speed Control, and Actuators.

Type: MicroSim
**sim-id:** differential-drive-simulator<br/>
**Library:** p5.js<br/>
**Status:** Specified

Create a p5.js MicroSim with a 700 × 450 canvas. Show a top-down view of the robot (a rectangle with L and R labels for left and right wheels).

Two vertical sliders on the left panel:
- "Left wheel speed" from -100% to +100%
- "Right wheel speed" from -100% to +100%

The robot animates in the top-down view, turning and moving based on the differential of the two speeds. Use simple Euler integration to update position and heading each frame. Show the robot's path as a fading trail of dots.

Preset buttons below the sliders: "Forward", "Backward", "Spin Left", "Spin Right", "Gradual Left", "Gradual Right". Each sets the sliders to the correct values and starts the animation.

A "Reset position" button returns the robot to center.

Learning objective (Bloom's Taxonomy — Applying): students predict and verify robot motion from left/right speed ratios.

Responsive: redraw on window resize.