Design, Fabricate, and Test a Prototype Heavy-Duty Kinematic Base for NIF Diagnostics

Introduction:

LLNL-POST-675585

J. M. Falcao*, R. L. Hibbard, and K. M. Skulina

Results:

Methods:

Conclusion:

California Polytechnic State University San Luis Obispo*, NIF, Lawrence Livermore National Laboratory

Abstract: The National Ignition Facility (NIF) is a complex research facility that requires the work of engineers and scientists to optimize every process and hardware piece within the system to achieve the best results. The Snout installation using the Kinematic Base assembly is one of the most critical features of NIF’s Target

Diagnostics Snout System that needs to be improved. The Kinematic Base is what holds the Snout under a semi-exact constraint configuration to minimize misalignment in all directions. As NIF’s Target Diagnostics Snout System is enhanced with more hardware and complexity, the Kinematic Base needs to be enhanced as well to keep up. A new kinematic base will be created to handle all the new hardware and make the operations of NIF’s Target Diagnostics Snout System more efficient.

• NIF typically uses 1-2 snouts on a shot and performs 6-8 shots on a weekly basis. These snouts have to be installed and removed routinely to a required repeatability.

• The objective of this project is to design, fabricate, and test a prototype of a heavy duty kinematic base that can still achieve the required repeatability and also have a more operator-friendly design to improve the ergonomics of snout exchanges.

• The Kinematic Base designs were modeled in Creo and tested to see which design would best satisfy the requirements. The Simple Latching Mechanism appeared to be the best design.

• The new Kinematic Base design will be fabricated and tested so that the results can be compared

with the results of the original Kinematic Base design that was tested.

Latches

• The original Snout and Kinematic Base assembly was tested to determine its responses to given loads. This data gave a quantitative perspective of what features were critical for the new design.

• Ideas were developed from brainstorming multiple solutions, which resulted in many great designs

that were reviewed and evaluated. The list of designs were narrowed down to five final designs.

• The design that ranked the best with respect to the requirements would then be fabricated and tested.

• Design 1 was selected as being the ideal candidate for meeting the requirements. • The newly fabricated Kinematic Base prototype is still in the process of being tested. • It is anticipated that this new design will speed up the snout exchange process and handle the

loading of additional equipment, thus making each NIF shot more efficient than before. • Future plans include additional modifications to optimize the Kinematic Base even further.

Snout

Snout and KB Assembly

Test Setup Table 2: Deflection of Original Assembly Design

Design 1 - Simple Latching Mechanism

Design 2 - L Brackets with Locking Latches

Design 3 - Hooking Mechanism

Design 4 - Slot Grooves Design 5 - Spring Ball Mechanism

Snout KB KB Assembly

Table 1: Requirements 1 The Kinematic Base shall hold up to 133 N from a

distance that will be 700 mm from the Kinematic Base. 2 The position repeatability of the Kinematic Base

shall be at least 75 μm in the x, y, and z directions. 3 The Kinematic Base design should be more

operator-friendly than its original design. 4 The Kinematic Base shall be backwards compatible.