e Open AUC Project includes software for operating the analytical ultracentrifuge. In order to accommodate diverse optical systems, the operating software is divided into “building block” modules that are interconnected using TCP/IP communications. The four building block modules that make up the operating software are: (1) machine services, (2) protocol services, (3) sample services, and (4) optical system operations (OSO). These modules are collectively called Analytical Ultracentrifuge-Advanced Operating System (AU-AOS).The machine services module (MSM) controls centrifuge operation using ASCII commands that follow the XML-RPC standard. The draft standard for the commands is available http://www.rasmb.bbri.org/rasmb/AOS/Open_AUC_Project/MachineServices/. Any computer with network connectivity may connect to and operate the CFA through TCP/IP communications.
The protocol services module (PSM) provides the information necessary to conduct an experiment, including the hardware description needed to operate optical detectors (sample holder angles and radii) and the method used (e.g. rotor speed, temperature, temperature tolerance, acceleration, braking, duration at each speed, any delay after reaching speed prior to data acquisition, time between data acquisition events and duration of the experiment) to collect the data. The identities of the protocol developer and user are kept with this information and saved in a database. A draft standard database structure is available (Langhorst 2008) and is described in “Proposed data analysis and data management infrastructure”.
The sample services module (SSM) includes information about the solvent and solute properties, and the calculations needed to interpret AUC results (Langhorst 2008; Laue et al. 1992). Both a desktop and a web-served version of this module will be available.
Optical system operations: Separate modules are required to run the hardware for the different optical systems. These will be written using the Open AUC Project standards for communications with the Protocol services and Data handling services. The TCP/IP communications provide relatively low-speed communications, meaning that any time-critical code must be contained within the OSO modules for a specific optical system.