Source code for instruments.Motor_KST_ZST
# the Motor class
#import serial
import threading
from struct import unpack
import logging
[docs]def int2hexStr(integer, numberOfBytes):
'''
Convert an integer to its corresponding bytearray
:param integer: the number we want to convert
:type integer: Integer
:param numberOfBytes: The number of bytes
:type numberOfBytes: Integer
:returns: Mutable sequence of integers of type bytearray
'''
bytes = []
for i in range(numberOfBytes):
bytes.append(integer & 0x0FF)
integer = integer >> 8
return bytearray(bytes)
[docs]def hexString(data):
'''
Creates a string that is a byte sequense of the hex values input
:param data: Example is '0A 23 34 56'
'''
h_str = ''
data = data.split(' ')
for byte in data :
h_str += r'\x' + byte
return h_str.decode('string_escape')
# setup the Logger
# -> should be done once
# initialize the logger
logger = logging.getLogger(__name__)
logger.setLevel(logging.DEBUG)
# create console handler and set level to debug
ch = logging.StreamHandler()
ch.setLevel(logging.DEBUG)
# create formatter
formatter = logging.Formatter('[%(asctime)-15s] %(ClassName)s<%(com_port)s>: %(message)s')
# add formatter to ch
ch.setFormatter(formatter)
# add ch to logger
logger.addHandler(ch)
[docs]class Motor_KST_ZST(object):
'''This class models a motor for stages'''
def __init__(self, serial):
'''
Constructor method
:param serial: the serial object that that corresponds to the port the motor is conected
:type serial: serial object
'''
self.serial = serial #
self.position = 0 # the position of the motor in steps
self.zeros_position = 0 # the zero position
self._count = -1 # internal step count from controller
# request some info from controller to trigger the reading process
self.serial.flushInput()
self.serial.flushOutput()
# MGMSG_HW_REQ_INFO
self.serial.write(hexString('05 00 00 00 50 01'))
self.serial.read(90) # just read the response
# get the logger we loaded once in the begining
self.logger = logger
# extra class info - for logger
self.ext = {'com_port': self.serial.port, 'ClassName': 'Motor'}
[docs] def delta_move(self, steps):
'''
Relative rotation onpos the motor
:param steps: the number of steps to move (negative -> backwards)
:type steps: Integer
'''
self.position += steps
# MGMSG_MOT_MOVE_RELATIVE extended
self.serial.write(hexString('48 04 06 00 D0 01')) # header
self.serial.write(hexString('01 00')) # chanel id
self.serial.write(int2hexStr(steps, 4)) # relative distance
self.move_complete()
[docs] def abs_move(self, steps):
'''
Relative rotation on the motor
:param steps: the endpoint of motion
:type steps: Integer
'''
# MGMSG_MOT_MOVE_RELATIVE extended
self.serial.write(hexString('48 04 06 00 D0 01')) # header
self.serial.write(hexString('01 00')) # chanel id
self.serial.write(int2hexStr(steps - self.position, 4)) # absolute distance
self.position = steps
# wait until move is complete
self.move_complete()
[docs] def get_position(self):
'''return the motors current position'''
return self.position
[docs] def set_as_zero(self, new_zero):
'''change the origin (zero)'''
self.zeros_position = new_zero
self.position -= new_zero
[docs] def set_vel_params(self, vel_init, accel, vel_fin):
'''
Set the velocity parameters for the motor
:param vel_init: initial velocity (steps / sec)
:type vel_init: Integer
:param accel: acceleration (steps / sec^2)
:type accel: Integer
:param vel_fin: max(final) velocity (steps / sec)
:type vel_fin: Integer
'''
# MGMSG_MOT_SET_VELPARAMS
self.serial.write(hexString('13 04 0E 00 D0 01')) # head
self.serial.write(hexString('01 00')) # chanel id
self.serial.write(int2hexStr(vel_init, 4)) # initial velocity
self.serial.write(int2hexStr(accel, 4)) # acceleration
self.serial.write(int2hexStr(vel_fin, 4)) # final velocity
[docs] def close(self):
'''releases motor resources'''
self.serial.close()
def __str__(self):
'''
<For Debugging Purposes>
gives information relevant to the motor state
'''
return 'position: ' + str(self.position) + '\nzeros-position: ' + str(self.zeros_position)
[docs] def move_complete(self):
'''
Waits until the MOVE_COMPLETE message is received by the controller.
Helper-function for delta_move() and abs_move() functions.
'''
self.serial.reset_input_buffer()
# read the beginning of the header
response = self.serial.read(2)
while response != hexString('64 04'): # MGMSG_MOT_MOVE_COMPLETED
response = self.serial.read(2)
# read the rest of the structure (20 bytes total)
response_rest = self.serial.read(18)
self._count = unpack('<l', response_rest[6:10])[0]
# DEBUG
self.logger.debug('move complete {}'.format(self._count), extra=self.ext)
self.isMoving = False
def _get_count(self):
''':returns: the count'''
return self._count
def _go_to_abs(self, steps):
# MGMSG_MOT_MOVE_RELATIVE extended
self.serial.write(hexString('53 04 06 00 D0 01')) # header
self.serial.write(hexString('01 00')) # chanel id
self.serial.write(int2hexStr(steps, 4)) # absolute distance
self.position = steps
self.move_complete()
'''
Copyright (C) 2017 Robert Polster
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
'''
