Merge pull request #124 from decarlof/master

Fix bug with the rotation motor speed calculation

docs/source/tomoScanApp.rst

@@ -1247,10 +1247,13 @@ Interlaced scan
     - Flag controlling whether the scan is regualr or interlaced. Choices are 'No' and 'Yes'. When "No" the angles are equally spaced using the Start angle, # of angles and Angle step parameters. When 'Yes' the list of angles is read from a file.
   * - $(P)$(R)InterlacedFileName
     - waveform
-    - The file name containing the list of interalced angles.
-  * - $(P)$(R)InterlacedRetakeFlat
-    - busy,
-    - Interlaced retake flat. Choices are 'Done' and 'Capture'. When 'Capture' a new set of flat field images will be collected.
+    - The file name containing the list of interalced angles in npy format.
+  * - $(P)$(R)InterlacedFileName
+    - waveform
+    - Interlaced file name containing the numpy list of angles to collect in interlaced mode.
+  * - $(P)$(R)StabilizationTime
+    - ao
+    - Settling time after the rotary stage motion is completed (used only in step scans).
 
 tomoScan_32ID_settings.req
 ~~~~~~~~~~~~~~~~~~~~~~~~~~

tomoscan/tomoscan_pso.py

@@ -91,9 +91,6 @@ def begin_scan(self):
         # Call the base class method
         super().begin_scan()
 
-        # Compute the time for each frame
-        time_per_angle = self.compute_frame_time()
-        self.motor_speed = np.abs(self.rotation_step) / time_per_angle
         time.sleep(0.1)
 
         # Program the stage driver to provide PSO pulses
@@ -276,10 +273,7 @@ def compute_positions_PSO(self):
         Assign the fly scan angular position to theta[]
         '''
         overall_sense, user_direction = self._compute_senses()
-        # Get the distance needed for acceleration = 1/2 a t^2 = 1/2 * v * t
-        motor_accl_time = float(self.epics_pvs['RotationAccelTime'].get()) # Acceleration time in s
-        accel_dist = motor_accl_time / 2.0 * float(self.motor_speed) 
-
+
         # Compute the actual delta to keep each interval an integer number of encoder counts
         encoder_multiply = float(self.epics_pvs['PSOCountsPerRotation'].get()) / 360.
         raw_delta_encoder_counts = self.rotation_step * encoder_multiply
@@ -292,6 +286,13 @@ def compute_positions_PSO(self):
         # Change the rotation step Python variable and PV
         self.rotation_step = delta_encoder_counts / encoder_multiply
         self.epics_pvs['RotationStep'].put(self.rotation_step)
+
+        # Compute the time for each frame
+        time_per_angle = self.compute_frame_time()
+        self.motor_speed = np.abs(self.rotation_step) / time_per_angle
+        # Get the distance needed for acceleration = 1/2 a t^2 = 1/2 * v * t
+        motor_accl_time = float(self.epics_pvs['RotationAccelTime'].get()) # Acceleration time in s
+        accel_dist = motor_accl_time / 2.0 * float(self.motor_speed) 
 
         # Make taxi distance an integer number of measurement deltas >= accel distance
         # Add 1/2 of a delta to ensure that we are really up to speed.