Maneuvers with Speed Control

With the Feedback 360° servos, scripts can control the speed of each wheel from a full speed of 2 turns/second forward to 2 turns/second backward. 

After adding the feedback360 module to the micro:bit filesystem and importing it, the drive.speed method takes left and right wheel speeds in terms of 64ths of a turn/second.  Positive values are for forward, and negative values are for reverse.    


Maneuver Script

Let’s first repeat the familiar forward, backward, left, right script using Feedback 360° speed control.  We’ll use a half speed of 64, which is about the same as the continuous rotation servo’s top speed of 130.  Unlike the continuous rotation servos, the Feedback 360° servos should not need any left/right speed value adjustments to straighten out the cyber:bot’s forward/backward travel.

  • Add five AA batteries to your cyber:bot robot’s battery pack, and plug the battery pack’s barrel plug into the cyber:bot board’s barrel jack.
  • Connect the micro:bit in the cyber:bot to your computer with a USB cable.
  • Set the PWR switch to 1.
  • Right-click the link below for speeds_forward_left_right_backward.hex, and select Save link as…



Maneuver Tests

  • Disconnect the cyber:bot’s micro:bit from the USB cable.
  • Set it on the floor
  • Set the PWR switch to 2.
  • Verify that the cyber:bot:
    • Rolls forward for 2 seconds
    • Rotates left for 1 second
    • Rotates right for 1 second
    • Rolls backward for 2 seconds