Question

我正在寻找有关如何为电动机定义初始位置的建议，以便可以跟踪相对于该点的当前角度位置。我使用步进电机，因此要移动到给定角度，我会计算步数。我目前有一个伪造某种PWM信号并以给定角度和一定速度和方向移动电机的函数。看起来像这样：

def RotMotor(SPIN, DPIN, direction, degrees, speed):
    GPIO.output(DPIN, direction)
    #For precise control the number of steps required to move to a given angle 
    #is calculated by the following line of code
    num_steps = (float(degrees) / float(360)) * 800
    #The sleep time is derived from the input RPM by converting RPM to time 
    #between each step
    sleeptime = 1 / ((float(speed) * 800) / 60)
    print('Taking ' + str(num_steps) + ' steps at ' + str(speed) + ' RPM.')
    #This while loop will take the calulated number of steps and count each 
    #step the motor makes in moving to its next point
    while num_steps > 0:
        GPIO.output(SPIN, 1)
        #The sleep function is called twice (High duration + Low Duration)
        time.sleep(sleeptime / 2)
        GPIO.output(SPIN, 0)
        #Second call of sleep function. Sleep function 1 + Sleep function 2 = 
        #Time for One Step
        time.sleep(sleeptime / 2)
        #Count 1 step
        num_steps -= 1

我想做的是开发一种方法，可以将此功能提供给职位列表，以便于：

1。）知道它从哪里开始是零 2.）知道如果它处于90度并且被告知要转到180度，那么它将移动90度。

我之前说过我的功能将通过角度移动。我的目标是移到角度。然后，当我的列表结束时，它将回到零，而不必在列表中包括该坐标。

我对需要做的事情含糊不清，但是在这一点上我很愿意提出建议。感谢您的任何反馈。

Answer 1

我为对这个问题感兴趣的人提供了一个简单的解决方案。与其解释，我只是在这里发布代码供任何人尝试。

'''
This code is used to drive two NEMA 17 stepper motors both driven by their own A4988 
driver circuit. The step resolution is set to 1/4 steps, which results in 800 steps 
per revolution for this specific motor. If you use this code be sure to change the number 
800 anywhere in this code to your own motors steps per revolution.
'''
#!/usr/bin/env python

#Importing all relevant packages

import os
import RPi.GPIO as GPIO
import numpy
import time

#Defining GPIO setup (STEP PINS (odd) AND DIRECTION PINS (even) FOR EACH MOTOR)

PINS = [11, 12, 15, 16]
GPIO.setmode(GPIO.BOARD)
GPIO.setwarnings(False)
GPIO.setup(PINS, GPIO.OUT)

#Initialize a list that stores the amount of steps taken for each coordinate for the duration of the program

mem1 = [0]
mem2 = [0]

#Function to tell a motor how to move based on direction (CW / CCW), how many degrees to move, and what speed to move at (RPM)
#For precise control the number of steps required to move to a given angle is calculated by the following line of code

def RotMotor(SPIN, DPIN, direction, degrees, speed, memory):
    pos = sum(memory)
    num_steps = ((float(degrees) / float(360)) * 800) - pos
    memory.append(num_steps)
    if num_steps < 0:
        x = abs(num_steps)
        dir = GPIO.output(DPIN, 1)
    else:
        x = num_steps
        GPIO.output(DPIN, 0)
    sleeptime = 1 / ((float(speed) * 800) / 60)
    print('Taking ' + str(num_steps) + ' steps at ' + str(speed) + ' RPM.')
    while x > 0:
        GPIO.output(SPIN, 1)
        time.sleep(sleeptime / 2)
        GPIO.output(SPIN, 0)
        time.sleep(sleeptime / 2)
        x -= 1

#THE FOLLOWING LINES ARE QUICK CODE FOR TESTING.

Motor1Ins = []
Motor2Ins = []

angles = [45, 90, 135, 180, 225, 270, 315, 360, 315, 270, 225, 180, 135, 90, 45, 0]

for i in angles:
   Motor1Ins.append([11, 12, i, 20, mem1])
   Motor2Ins.append([15, 16, i, 20, mem2])

try:
   while True:
      for s, d, theta, t, MotMem in Motor1Ins:
         RotMotor(s, d, theta, t, MotMem)
         time.sleep(0.5)
      for s, d, theta, t, MotMem in Motor2Ins:
         RotMotor(s, d, theta, t, MotMem)
         time.sleep(0.5)
except KeyboardInterrupt():
   RotMotor(11, 12, 0, 20, mem1)
   RotMotor(15, 16, 0, 20, mem2)

GPIO.cleanup()

从本质上讲，我创建了一个充当内存的列表，然后使用一些逻辑来基于其记忆来决定运动的工作方式。我认为我应该在其他地方写入文件，然后替换当前的内存值，而不是出于内存原因而让列表不断增长，但这暂时可行。

记住步进电机中的角位置

1 个答案: