Acquisition settings

This section details the acquisition settings that can be specified for measurement on a quadrupole.

json dictionary containing the default settings contained in settings/default.json

  {
  "injection_duration": 0.2, # injection duration of one pulse within an injection cycl
  "nb_stack": 1, # number of injection cycles (e.g. 'nb_stack'=1 means one positive and one negative pulse)
  "sampling_interval": 2, # sampling interval in ms
  "tx_volt": 5, # injection voltage in V for strategy 'constant' or starting V_AB for strategy 'vmax' or 'vmin'
  "duty_cycle": 0.5, # duty cycle for the injection (0-1)
  "strategy": "constant", # injection strategy ("constant", "vmax" or "vmin")
  "fw_in_csv": true, # full waveform saved in a the main csv file. Read by run_sequence()
  "fw_in_zip": true, # full waveform saved in a separate zip file. Read by run_sequence()
  "export_path": "data/measurements.csv" # path for data output. Read by run_sequence()
  "nb_meas": 1, # number of sequences repeated when calling run_mutlitple_sequences()
  "sequence_delay": 1, # sleeping time between repeated sequences when calling run_multiple_sequences()
  }

For more information on these settings, see the API doc for ohmpi.ohmpi.OhmPi.run_measurement(), ohmpi.ohmpi.OhmPi.run_measurement() and ohmpi.ohmpi.OhmPi.run_measurement()

In addition to these default settings, and for advanced users, additional settings related to the injection strategy “vmax” and “vmin” can also be specified in the json settings file as follows:

Dictionnary containing the advanced settings that can be added to settings/default.json

  {
  "vab_max": null, # maximum V_AB (in V) bounding the vmax injection strategy. Value is capped by vab_max from hardware config. Default is None, which means vmax strategy bounded by hardware vab_max from hardware config.
  "iab_max": null, # maximum I_AB (in mA) bounding the vmax injection strategy. Value is capped by iab_max from hardware config. Default is None, which means vmax strategy bounded by hardware iab_max from hardware config.
  "vmn_max": null, # maximum V_mn (in mV) bounding the vmax injection strategy. Value is capped by vmn_max from hardware config. Default is None, which means vmax strategy bounded by hardware vmn_max from hardware config.
  "vmn_min": null, # minimum V_mn (in mV) bounding the vmax injection strategy. Value is capped by vmn_min from hardware config. Default is None, which means vmax strategy bounded by hardware vmn_min from hardware config.
  }

For more information on these settings, see the API donc for OhmPi.run_measurement().