frappy/secop_psi/phytron.py
Markus Zolliker 39171fe06e add limits to phytron
Change-Id: I431374efab7a858db6a652f78533b13b12ba6d57
2022-05-19 18:05:52 +02:00

231 lines
9.5 KiB
Python

# -*- coding: utf-8 -*-
# *****************************************************************************
#
# 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 2 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, write to the Free Software Foundation, Inc.,
# 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#
# Module authors:
# Markus Zolliker <markus.zolliker@psi.ch>
#
# *****************************************************************************
"""driver for phytron motors"""
from secop.core import Done, Command, EnumType, FloatRange, IntRange, \
HasIO, Parameter, Property, Drivable, PersistentMixin, PersistentParam, \
StringIO, StringType, TupleOf
from secop.errors import CommunicationFailedError, HardwareError, BadValueError
from secop.lib import clamp
class PhytronIO(StringIO):
end_of_line = '\x03' # ETX
timeout = 0.2
identification = [('0IVR', 'MCC Minilog .*')]
def communicate(self, command, expect_response=True):
for ntry in range(5, 0, -1):
try:
head, _, reply = super().communicate('\x02' + command).partition('\x02')
if reply[0] == '\x06': # ACK
if len(reply) == 1 and expect_response:
raise CommunicationFailedError('empty response')
break
raise CommunicationFailedError('missing ACK %r' % reply)
except Exception as e:
if ntry == 1:
raise
self.log.warning('%s - retry', e)
return reply[1:]
class Motor(PersistentMixin, HasIO, Drivable):
axis = Property('motor axis X or Y', StringType(), default='X')
address = Property('address', IntRange(0, 15), default=0)
speed_factor = Property('steps / degree', FloatRange(0, None), default=2000)
encoder_mode = Parameter('how to treat the encoder', EnumType('encoder', NO=0, READ=1, CHECK=2),
default=1, readonly=False)
value = Parameter('angle', FloatRange(unit='deg'))
target = Parameter('target angle', FloatRange(unit='deg'), readonly=False)
speed = Parameter('', FloatRange(0, 20, unit='deg/s'), readonly=False)
accel = Parameter('', FloatRange(2, 250, unit='deg/s/s'), readonly=False)
encoder_tolerance = Parameter('', FloatRange(unit='deg'), readonly=False, default=0.01)
offset = PersistentParam('', FloatRange(unit='deg'), readonly=False, default=0)
sign = PersistentParam('', IntRange(-1,1), readonly=False, default=1)
encoder = Parameter('encoder reading', FloatRange(unit='deg'))
sameside_offset = Parameter('offset when always approaching from the same side',
FloatRange(unit='deg'), readonly=False, default=0)
abslimits = Parameter('abs limits (raw values)', default=(0, 0),
datatype=TupleOf(FloatRange(unit='deg'), FloatRange(unit='deg')))
userlimits = PersistentParam('user limits', readonly=False, default=(0, 0), initwrite=True,
datatype=TupleOf(FloatRange(unit='deg'), FloatRange(unit='deg')))
ioClass = PhytronIO
fast_poll = 0.1
_sameside_pending = False
_mismatch_count = 0
_rawlimits = None
def earlyInit(self):
super().earlyInit()
if self.abslimits == (0, 0):
self.abslimits = -9e99, 9e99
if self.userlimits == (0, 0):
self._rawlimits = self.abslimits
self.read_userlimits()
self.loadParameters()
def get(self, cmd):
return self.communicate('\x02%x%s%s' % (self.address, self.axis, cmd))
def set(self, cmd, value):
self.communicate('\x02%x%s%s%g' % (self.address, self.axis, cmd, value), False)
def set_get(self, cmd, value, query):
self.set(cmd, value)
return self.get(query)
def read_value(self):
prev_enc = self.encoder
pos = float(self.get('P20R')) * self.sign - self.offset
if self.encoder_mode != 'NO':
enc = self.read_encoder()
else:
enc = pos
status = self.communicate('\x02%xSE' % self.address)
status = status[0:4] if self.axis == 'X' else status[4:8]
self.log.debug('run %s enc %s end %s', status[1], status[2], status[3])
status = self.get('=H')
if status == 'N':
if self.encoder_mode == 'CHECK':
e1, e2 = sorted((prev_enc, enc))
if e1 - self.encoder_tolerance <= pos <= e2 + self.encoder_tolerance:
self.status = self.Status.BUSY, 'driving'
else:
self.log.error('encoder lag: %g not within %g..%g',
pos, e1, e2)
self.get('S') # stop
self.status = self.Status.ERROR, 'encoder lag error'
self.setFastPoll(False)
else:
self.status = self.Status.BUSY, 'driving'
else:
if self._sameside_pending:
# drive to real target
self.set('A', self.sign * (self.target + self.offset))
self._sameside_pending = False
return pos
if (self.encoder_mode == 'CHECK' and
abs(enc - pos) > self.encoder_tolerance):
if self._mismatch_count < 2:
self._mismatch_count += 1
else:
self.log.error('encoder mismatch: abs(%g - %g) < %g',
enc, pos, self.encoder_tolerance)
self.status = self.Status.ERROR, 'encoder does not match pos'
else:
self._mismatch_count = 0
self.status = self.Status.IDLE, ''
self.setFastPoll(False)
return pos
def read_encoder(self):
if self.encoder_mode == 'NO':
return self.value
return float(self.get('P22R')) * self.sign - self.offset
def read_speed(self):
return float(self.get('P14R')) / self.speed_factor
def write_speed(self, value):
inv_factor = float(self.get('P03R'))
if abs(inv_factor * self.speed_factor - 1) > 0.001:
raise HardwareError('speed factor does not match %g' % (1.0 / inv_factor))
return float(self.set_get('P14S', int(value * self.speed_factor), 'P14R')) / self.speed_factor
def read_accel(self):
return float(self.get('P15R')) / self.speed_factor
def write_accel(self, value):
if abs(float(self.get('P03R')) * self.speed_factor - 1) > 0.001:
raise HardwareError('speed factor does not match')
return float(self.set_get('P15S', int(value * self.speed_factor), 'P15R')) / self.speed_factor
def _check_limits(self, *values):
for name, (mn, mx) in ('user', self._rawlimits), ('abs', self.abslimits):
mn -= self.offset
mx -= self.offset
for v in values:
if not (mn <= v <= mx):
raise BadValueError('%s limits violation: %g <= %g <= %g' % (name, mn, v, mx))
v += self.offset
def write_target(self, value):
if self.status[0] == self.Status.ERROR:
raise HardwareError('need reset')
self.status = self.Status.BUSY, 'changed target'
self._check_limits(value, value + self.sameside_offset)
if self.sameside_offset:
# drive first to target + sameside_offset
# we do not optimize when already driving from the right side
self._sameside_pending = True
self.set('A', self.sign * (value + self.offset + self.sameside_offset))
else:
self.set('A', self.sign * (value + self.offset))
self.setFastPoll(True, self.fast_poll)
return value
def read_userlimits(self):
return self._rawlimits[0] - self.offset, self._rawlimits[1] - self.offset
def write_userlimits(self, value):
self._rawlimits = [clamp(self.abslimits[0], v + self.offset, self.abslimits[1]) for v in value]
value = self.read_userlimits()
self.saveParameters()
return value
def write_offset(self, value):
self.offset = value
self.read_userlimits()
self.saveParameters()
return Done
def stop(self):
self.get('S')
@Command
def reset(self):
"""reset error, set position to encoder"""
self.read_value()
if self.status[0] == self.Status.ERROR:
enc = self.encoder + self.offset
pos = self.value + self.offset
if abs(enc - pos) > self.encoder_tolerance:
if enc < 0:
# assume we have a rotation (not a linear motor)
while enc < 0:
self.offset += 360
enc += 360
self.set('P22S', enc * self.sign)
self.saveParameters()
self.set('P20S', enc * self.sign) # set pos to encoder
self.read_value()
# self.status = self.Status.IDLE, ''
# TODO:
# '=E' electronics status
# '=I+' / '=I-': limit switches
# use P37 to determine if restarted