Review and Practice

Self-check

• In this activity, you:
  • Used pushbuttons to set the direction the servo horn points to.  
  • Adjusted the limits to the servo horn’s button controlled motion.
  • Adjusted the rate the servo horn rotates.
• Were you able to control the limits of the servo horn’s rotation?
• Were you able to adjust the rate the servo turned?
• You also learned the difference between angular position and angular velocity.
• Were you able to calculate angular velocity?

Questions

1. List some common items that servo motors can be used to control.
2. To what does the terminology “horn angle” refer?
3. What is “angular velocity”?
4. When calculating angular velocity, is counterclockwise rotation of the servo horn positive or negative?
    

Exercises

1. What values are used to set the full range of motion (0° to 180°) for the servo horn?
2. What is the approximate angular position of the servo horn when in pin16.write_analog(value) value is set to 77?:
3. If it takes 1.5 seconds for the horn to rotate from 45° to 135°, what is the angular velocity?  
4. If it takes 2.3 seconds for the horn to rotate from 180° to 45°, what is the angular velocity?  
    

Projects

1. Change the range of motion of the servo horn so that it moves through a range of only 45 degrees. Which 45 degrees exactly is up to you.
2. Create a script to change the angular velocity so the horn turns twice as fast to the right as it turns to the left.