Goal:
- Build a car with a single motor driving two wheels.
- Add rigidity to wobbly components.
- Program car to travel prescribed distance.
Concepts:
- Car motor-drive types.
- Structural rigidity.
- Data collection.
- Tables.
- Variation.
- Relation between wheel circumference, number of rotations, and distance traveled.
Materials:
- Lego spike components, including long red axle.
- Sewing tape measure.
- Metal tape measure.
Preparation:
- Charge hub.
- Try building car from photos, below. Don’t worry if you get stuck or something doesn’t make sense. We’ll do it during the lesson.
Procedure:
Build car following these steps:
Completed car. Front.
Completed car. Side.
Completed car. Side.
Completed car. Underneath.
Components of simple car.
Mount motor to frame with three black pins.
Short axle for attaching motor to wheel.
Underneath view before mounting hub.
Bushing keeps wheel from rubbing frame.
Bushing on outside of wheel to keep it from falling off.
Center hole to support axle. Mounts to frame with two black pins.
Axle support mounted on frame.
Front of frame before adding yellow beams.
Gray piece for mounting ball underneath frame.
Ball ready to mount.
Yellow beams added to keep ball from wobbling.
Motor cable will plug into hub.
- Watch videos of actual car robots.
- Program car to travel desired number of wheel rotations.
- Measure distance traveled vs. wheel rotations.
- Make table of distance vs. rotations.
- Measure circumference of wheel with tape measure.
- What is relation between circumference and distance traveled?
- Program car to travel desired distance in centimeters.
Homework:
Describe homework