def move(self, position):
"""Move to the requested position.
If the motor is already moving, then update the target position.
Return an object that may be used to check
whether the move is complete (see move_status).
"""
id = self._last_move_id
if self.program_running():
self._interrupt_move()
self.mcm.set_global('gp0', position)
start = ptime.time()
else:
self.mcm.set_global('gp0', position)
self.mcm.start_program()
start = ptime.time()
self._target_position = position
id += 1
self._last_move_id = id
self._move_status[id] = {'start': start, 'status': 'moving', 'target': position}
return id
def run(self):
lastUpdate = ptime.time()
while True:
with self.lock:
if self._quit:
break
target = self.target
speed = self.speed
velocity = self.velocity
currentMove = self.currentMove
pos = self.pos
now = ptime.time()
dt = now - lastUpdate
lastUpdate = now
if target is not None:
dif = target - pos
dist = np.linalg.norm(dif)
stepDist = speed * dt
if stepDist >= dist:
self._setPosition(target)
self.currentMove._finished = True
self.stop()
else:
unit = dif / dist
step = unit * stepDist
self._setPosition(pos + step)
elif self.velocity is not None and not np.all(velocity == 0):
self._setPosition(pos + velocity * dt)
time.sleep(self.interval)
def measureSpeedTable(dev, drive, dist=3e-3):
"""Measure table of speeds supported by the stage.
Warning: this function moves the stage to (0, 0, 0); do not
run this function unless you know it is safe for your setup!
"""
from acq4.pyqtgraph import ptime
v = []
for i in range(16):
pos = (dist, 0, 0)
dev.moveTo(drive, [0,0,0], 'fast')
start = ptime.time()
dev.moveTo(drive, pos, i, timeout=100)
stop = ptime.time()
dt = stop - start
v.append(dist / dt)
print('%d: %0.4g, # %0.2g m / %0.2g s' % (i, v[-1], dist, dt))
dist *= 1.1
return v
def percentDone(self):
"""Return an estimate of the percent of move completed based on the
device's speed table.
"""
if self.isDone():
return 100
dt = ptime.time() - self._getStatus()[0]
if self._expectedDuration == 0:
return 99
return max(min(100 * dt / self._expectedDuration, 99), 0)
def run(self):
minInterval = 100e-3
interval = minInterval
while True:
try:
with self.lock:
if self.stopped:
break
maxInterval = self.interval
moveRequest = self.moveRequest
self.moveRequest = None
if moveRequest is None:
# just check for position update
if self.dev._checkPositionChange() is not False:
interval = minInterval
else:
interval = min(maxInterval, interval * 2)
else:
# move the drive
mid, drive, pos, speed = moveRequest
try:
with self.dev.dev.lock:
# record the move starting time only after locking the device
start = ptime.time()
with self.lock:
self._moveStatus[mid] = (start, False)
pos = self.dev.dev.moveTo(drive, pos, speed)
self.dev._checkPositionChange(drive, pos)
except Exception as err:
debug.printExc('Move error:')
try:
if hasattr(err, 'lastPosition'):
self.dev._checkPositionChange(
drive, err.lastPosition)
finally:
with self.lock:
self._moveStatus[mid] = (start, err)
else:
with self.lock:
self._moveStatus[mid] = (start, True)
time.sleep(interval)
except:
debug.printExc('Error in MPC200 monitor thread:')
time.sleep(maxInterval)
def sleep(self, until):
# Wait until some event occurs
# check for pause / stop while waiting
while True:
with self.lock:
if self._stop:
raise Exception("stopped")
paused = self._paused
frame = self._frame
if paused:
wait = 0.1
else:
if until == 'frame':
if frame is not None:
return
wait = 0.1
else:
now = ptime.time()
wait = until - now
if wait <= 0:
return
time.sleep(min(0.1, wait))
def start(self):
self._quit = False
self.lastUpdate = ptime.time()
Thread.start(self)