NetworkLoader

class sharpy.io.network_interface.NetworkLoader

SHARPy UDP data input and output interface.

The settings of this interface are to be used as the dictionary to the setting network_setting in the DynamicCoupled solver, which is the only one that is currently supported.

This interface allows for SHARPy to receive and send simulation data over the network using an UDP protocol.

The setting variables_filename is a filename to a YAML file that contains a list of the input or output variables. The example below shows an acceptable input

---
- name: 'control_surface_deflection' # variable name. those in the timestep_info are supported
  var_type: 'control_surface'
  inout: 'in'  # either `in`, `out` or `inout`
  position: 0  # control surface index
- name: 'pos'  # variable name
  var_type: 'node'  # type of variable. In this case a node variable. Others: `panel`, `control_surface`
  inout: 'out'
  position: 5  # node number
  index: 2  # vector index, in this case a 3d vector where the desired index is number 2
- name: 'gamma'
  inout: 'out'
  position: [0, 1, 2] # [i_surf, i_chordwise, i_spanwise]
  var_type: 'panel'
- name: 'psi'  # CRV
  inout: 'out'
  var_type: 'node'
  position: 3  # node id
  index: 2  # dimension index
...

All variables in the aero and structural timestep info classes datastructures are supported, with the addition of dt for the time increment and nt for the current time step number.

Note

If using a control surface input, make sure this control surface is given control_surface_type = 2 in the the case .aero.h5 file. Otherwise, the control surface will not move!

The relevant settings for the input and output sockets can be found in InNetwork and OutNetwork, respectively.

If the setting send_output_to_all_clients is True, then the clients from which the input signal is received will also be added to the destination client address book.

The input and output messages follow the example set by X-Plane RREF0 protocol. Thus, a message consists of a 5-byte header containing RREF0 followed by 8-bytes per variable, where the first 4-bytes correspond to the variable number (as ordered in the YAML file) as an integer and the latter 4-bytes correspond to the value of the variable in single precision float. The byte ordering is specified by the user.

A specific network log is created to detail the ins and outs of the communication protocol. The level of messages that are shown can be set in the settings.

See also

Endianness: https://docs.python.org/3/library/struct.html#byte-order-size-and-alignment

Note

The SHARPy input and output sockets do not time out.

Note

The first time step in a simulation with UDP inputs takes particularly long. Make sure your client has a sufficient time out time to avoid issues. After the first time step, the UDP should not delay the simulation.

Warning

There is a limitation, for the moment, on just one control surface being supported for UDP input.

The NetworkLoader takes the following settings:

Name	Type	Description	Default
variables_filename	str	Path to YAML file containing input/output variables	None
byte_ordering	str	Desired endianness byte ordering	little
input_network_settings	dict	Settings for the input network.:class:~sharpy.io.network_interface.InNetwork.	{}
output_network_settings	dict	Settings for the output network OutNetwork.	{}
send_output_to_all_clients	bool	Send output to all clients, including those from where the input is received.	False
received_data_filename	str	If not empty, writes received input data to the specified file.
log_name	str	Network log file name	./network_output.log
console_log_level	str	Minimum logging level in console.	info
file_log_level	str	Minimum logging level in log file.	debug