Purpose: Use a rack and pinion combined with a telescopic slide to simulate a controlled vertical lifting mechanism.

Exercise:1

Learning how vertical motion is created using rack and pinion

Assemble the rack and pinion with the MG995 servo motor in a vertical arrangement using this video and this assembly guide.

Recall the connection for MG995 Servo from the previous lessons. Use this sample code to test the movement of the pinion over the rack and telescopic slide.

1. Explain the goal of the activity, which is to lift and lower an object using a motorized mechanism.
2. Introduce the rack, pinion, servo motor, and telescopic slide and explain their roles.
3. Demonstrate how the servo rotates the pinion and moves the rack upward and downward.
4. Explain how the telescopic slide keeps the movement straight and prevents wobbling.
5. Discuss why a high torque MG995 servo and external 5V power are needed for lifting.
6. Demonstrate the CircuitPython code that controls the lifting motion.
7. Guide students through testing the lift with different loads.
8. Ask students to observe how mechanical design and motor power affect lifting performance.
9. How might friction, gravity and the length of the rack affect how smoothly and safely the lift moves up and down?
10. If we try to lift a much heavier object, will the MG995 servo still be strong enough and what mechanical or design changes could help the system lift more weight?