luseepy

OpSim: Simulation of the LuSEE-Night Operations Logic

About

Software for calculations related to operation control for LuSEE-Night, such power generation and management, data taking (science), comms etc.

Glossary

• modes: reference to the modes of the LuSEE-Night apparatus' operations, this choice is in order to conform with the convention in the "ConOps" document
  • science
  • main
  • powersave
• states: states of the devices as stipulated by the specific LuSEE mode.
• fade: an accounting factor, reflecting the loss of the battery capacity prior to launch. This is a constant that does not change during the actual operation.

Devices Included in the simulation

• UT -- Comm module
• PDU -- Power distribution
• PCDU -- The battery management circuit
• PFPS -- PFPS picket fance power supply
• DCB -- Flight computer

Folders in this repository

Configuration and data

1. config: configuration data, typically formatted in YAML
2. data: pre-calculated data to be fed to the simulator. The current format is HDF5 and a few older files in the numpy format are kept for reference only.

Please see the README file in the config folder for more detail on how these pieces of configuration relate to each other.

"Scripts"

1. scripts: an assembly of scripts, such as used in preparation of the "prefabricated" data on the position of celestial objects, to be later used in the simulation. The important one is prep-all. The main data format used for this purpose is hdf5.

Core software

1. notebooks: an assembly of notebooks to diagnose the data and run the simulation
2. nav contains utility accessor methods to interface various coordinate calculations
3. hardware: classes describing various elements of the LuSEE hardware
4. sim: the main simulator class

Unit test and CI

• the test folder contains scripts specifically designed for testing and CI, as opposed to the end user or production scenarios.

Docker

Work in progress -- this folder will keep the material necessary for the creation of the Docker images with OpSim on top of the base luseepy.

Archival/reference folders

1. The docs folder is reserved for the future documentation website materials (if needed)
2. In the reference folder there is a "sandbox" version of the original power calculation notebook (heavily modified and not to be used for anything practical) and some requisite inputs. Kept for continuity with the power calculation notebook.

Configuration details

The paths

• The variable LUSEEPY_PATH contains the path to the luseepy package. If set, its content will be prepended to sys.path. If not set, the software will depend on the PYTHONPATH.
• The variable LUSEEOPSIM_PATH contains the path to this (OpSim) package, in order to have an unambiguous reference when running it on top of luseepy and in other similar situations. If not set, the software will depend on the PYTHONPATH. In addition to location the Python modules, this variable is used to locate the data and configuration folders. If not set, the default will be '..', effectively corresponding to the case when the test scripts are run explicitely from their folder.

Dependencies

This software depends of the luseepy suite, plus the simpy package. This is typically handled by setting up an appropriate Python virtual environment. The hdf5 interface is provided via the h5py Python package, which happens to be already in luseepy so no separate installation is required.

lzma

In some Debian instances, the lzma Python package is missing, while it's needed for a few dependencies to work. One way to fix that is to do the `backport`` package installation in a virtual environment, and then define the path for it to be referenced, as shown in the following example:

export PYTHONPATH=/home/maxim/projects/lusee/luseepy:/home/maxim/projects/lusee/opsim:/home/maxim/.virtualenvs/lusee/lib/python3.10/site-packages/backports

MJD

The MJD gives the number of days since midnight on November 17, 1858. This date corresponds to 2400000.5 days after day 0 of the Julian calendar. MJD is still in common usage in tabulations by the U. S. Naval Observatory. Care is needed in converting to other time units, however, as a result of the half day offset (unlike the Julian date, the modified Julian date is referenced to midnight instead of noon) and because of the insertion of semiannual leap seconds (which are inserted at midnight).