This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Objectives ?The major objective stated in the recent renewal proposal was to fabricate one additional automounter, and to deploy it and an existing one. There are several minor objectives: we will create adaptors for the Rigaku Actor pucks and modify two of our automounters for Uni-Puck ?Actor puck intercompatibility, we will employ data-matrix readers to automate firm identification of specimens and to provide a link between the PXDB and user's LIMS, we will develop a multilayered automounter status analysis and forecasting client, we will quicken the crystal-cap drying to shorten dead time in the crystal screening duty cycle and develop a fast gripper-reconditioning method to eliminate delays in payload changes. Results ?The new automounter at X12C is based on the same second-generation design as the proven X29 device. However, it differs from its predecessors in two key aspects. Firstly, available space in the small X12C hutch, which is traversed by the X12B beam pipe, made it necessary to build this robot in the opposite hand of earlier machines. The underlying considerable engineering effort by Mary Carlucci (now with the NSLS-II Project) has resulted in a pair of designs that give us the unique flexibility to develop future robots to fit available space. Secondly, static considerations at X12C required that the specimen changer rest on an autonomous kinematic stand that follows the diffractometer on each of its alignments into the beam. Together with refined protocols for the mechanics of specimen change, this has allowed us to employ a 'soft mount'method that imparts only minute mechanical challenge to the goniometer and thus preserves its delicate alignment. Our automounters now take less than 3s to mount a crystal to the goniometer head or to retrieve one into the specimen dewar. This remarkable speed is a prerequisite to prevent icing, and consequently allow repeated mounting of one specimen for screening, data collection, or exposure with another beamlines'robot. Of course this fleetness is in part a consequence of the ingeniously simple design of the ALS-type sample changer, but our careful optimization of the protocols that direct the robot are equal contributors to this. We also have reduced the time interval between two successively mounted specimens by introducing 'cap dryers'that gently heat cystal caps and then blow them dry. While completely de-iced and dry specimen cycling can now be achieved in about 45s, this interval should be reduced further to match the fast crystal screening speed achievable at X29. There, screening can be carried out in about 30s when crystal centering is performed manually by the experimenter, or in about 60s with auto-centering software. The embedding of the automounters into the CBASS data collection programs was further advanced, primarily by implementing lessons learned from observing users. In particular, we have added a 'manual'robot operations mode, which lets users initiate every crystal mounting and retrieval. It is a great didactical device for the novice, and a valuable addition for the expert who may choose to escape preprogrammed routines when experience indicates an interesting or hopeless case. Plans ?Based on the historical growth of interest in the automation program, we expect that we will need to expand our capabilities in the near future, possibly with deployment of a new unit at X25. We have all the parts in place to meet increased demand rapidly. An array of software developments are planned, the better to integrate automounter operation into our CBASS data collection system. A first effort will expand an existing rudimentary robot status annunciator and create a graphic robot status analysis and forecasting client that will reflect the intricate interactions between the CBASS and the workings of the robot. When fully developed, it will also provide detailed escape and recovery pathways when unexpected events occur, particularly in support of remote participation. A second effort will focus on extracting from the C3D specimen auto-align program (obtained from the ESRF) those routines that simply and quickly center the loop into the beam cross hairs. This will provide a powerful addition to the remote participation toolkit by eliminating the time-consuming and sluggish image exchange with a remotely located crystallographer, and it should make auto-alignment competitive with a skilled experimenter at the beamline. A third effort will be directed towards integrating the use of kappa for crystal orientation with the use of automounters. Generally, we need to improve our web-based instructions and automounter web site to promote PXRR capabilities better, as well as to make our technology developments more completely available to the community. This activity, and an overdue gathering of builders and operators of cryogenic crystal automounters may well lead to a workshop in 2010 to address future needs at NSLS-II. Significance ?Automounters, when supported by anticipating but flexible software, are essential tools to advance automation and productivity of the data collection process carried out by visiting and remotely participating crystallographers, as well as by local staff, including our productive Mail-in scientists. We plan to exploit the robots'discreet and untiring performance for the benefit of proprietary users via the recently developed Q-project (see the software section), which is essentially a form of asynchronous remote participation. We entertain the possibility that project development aspects of the Mail-in program, the crystal screening, may enlist its clients as remote participants, and thus lead to an expansion of the scientist supported Mail-in program. Clearly, NSLS-II will provide crystallographers with unprecedented flux and truly fast data collections on real-time detectors that can best be exploited with automated equipment. Continuing development of automounters and their application to an increasingly broad set of experiments and methods is required to support the community with modern tools.
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