Control Single Servo

1. API Introduction

The API for controlling a single bus servo is:

Arm_serial_servo_write(id, angle, time)

Function: Controls the target angle of the bus servo.

Parameter Description:

id: The ID number of the servo to control, range 1~6. Each ID represents a servo. The lowest servo has ID 1, increasing upward, with the topmost servo having ID 6.

angle: The target angle for the servo. Except for servo 5 (ID=5), the control range for all servos is 0~180. The control range for servo 5 is 0~270.

time: The runtime for the servo movement. Within the valid range, for the same rotation angle, a smaller time value results in faster servo movement. Input 0 for maximum speed.

Return value: None.

2. Code

Code path:

~/dofbot_ctrl/scripts/03.ctrl_servo.ipynb

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#!/usr/bin/env python3
#coding=utf-8
import time
from Arm_Lib import Arm_Device
# Create robotic arm object
Arm = Arm_Device()
time.sleep(.1)

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# Control a single servo to move to a certain angle
id = 6
Arm.Arm_serial_servo_write(id, 90, 500)
time.sleep(1)

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# Control a servo to cycle through angles
id = 6
def main():
 while True:
 Arm.Arm_serial_servo_write(id, 120, 500)
 time.sleep(1)
 Arm.Arm_serial_servo_write(id, 50, 500)
 time.sleep(1)
 Arm.Arm_serial_servo_write(id, 120, 500)
 time.sleep(1)
 Arm.Arm_serial_servo_write(id, 180, 500)
 time.sleep(1)
 
try :
 main()
except KeyboardInterrupt:
 print(" Program closed! ")
 pass

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del Arm # Release the Arm object

Open the program file from Jupyter Lab and click the "Run All Cells" button on the Jupyter Lab toolbar. You will see the robotic arm's gripper continuously changing angles.

To exit, click the stop button on the toolbar.