Embedded Files
University of California, San Diego
Mechanical and Aerospace Engineering
MAE 156B: Senior Design Project (Winter 2024)
Background
The sponsor of this project, the PISCES laboratory, is a facility supported by the U.S. Department of Energy Office of Fusion Energy Sciences which studies how plasmas found in fusion energy systems interact with the material walls of plasma confinement devices. To study the effects of this plasma, the PISCES laboratory uses an RF plasma source to continuously subject material samples to a magnetically confined beam in an ultra-high vacuum environment. In the Summer of 2024 they plan to add a low current ion beam to this machine to simulate the effects of neutron damage on these material samples. The goal of this project is to create a device that will allow for characterization and calibration of the ion beam at the sample test location. There will be two beam diagnostic instruments: a scintillator which will measure the beam's location and spatial distribution, and a faraday cup which will measure the current of the beam. These two devices need to be moved into the beam line, while the plasma is off, and then each will be used individually to take measurements, then they need to be removed from the beamline for full operation of the machine.
The sponsor of this project, the PISCES laboratory, is a facility supported by the U.S. Department of Energy Office of Fusion Energy Sciences which studies how plasmas found in fusion energy systems interact with the material walls of plasma confinement devices. To study the effects of this plasma, the PISCES laboratory uses an RF plasma source to continuously subject material samples to a magnetically confined beam in an ultra-high vacuum environment. In the Summer of 2024 they plan to add a low current ion beam to this machine to simulate the effects of neutron damage on these material samples. The goal of this project is to create a device that will allow for characterization and calibration of the ion beam at the sample test location. There will be two beam diagnostic instruments: a scintillator which will measure the beam's location and spatial distribution, and a faraday cup which will measure the current of the beam. These two devices need to be moved into the beam line, while the plasma is off, and then each will be used individually to take measurements, then they need to be removed from the beamline for full operation of the machine.
Final Solution
The final design of the manipulator assembly includes several key components. These are comprised of the shielding, the diagnostic tools, the linear actuator, vacuum sealing, electronics, and the cooling system. The diagnostic tools are mounted near one end of a 24 inch steel rod that runs through a welded bellows and connects to a vacuum flange. The bellows and flange are part of a linear actuator that uses a motor to move a lead screw and translate one end of the bellows, causing it to contract or expand. With the bellows fully expanded, the diagnostic tools are placed in the center of the sample chamber and in the trajectory of the ion beam. When fully contracted, the diagnostic tools are brought to the edge of the sample chamber, nearly flush with the machine wall. The linear actuator is mounted through the use of a 6 inch flange nipple fitting to the 12 inch main flange, located on the top machine access port. The flanges used are ConFlat metal gasket flanges that allow an ultra-high vacuum seal to be maintained at all times.
The final design of the manipulator assembly includes several key components. These are comprised of the shielding, the diagnostic tools, the linear actuator, vacuum sealing, electronics, and the cooling system. The diagnostic tools are mounted near one end of a 24 inch steel rod that runs through a welded bellows and connects to a vacuum flange. The bellows and flange are part of a linear actuator that uses a motor to move a lead screw and translate one end of the bellows, causing it to contract or expand. With the bellows fully expanded, the diagnostic tools are placed in the center of the sample chamber and in the trajectory of the ion beam. When fully contracted, the diagnostic tools are brought to the edge of the sample chamber, nearly flush with the machine wall. The linear actuator is mounted through the use of a 6 inch flange nipple fitting to the 12 inch main flange, located on the top machine access port. The flanges used are ConFlat metal gasket flanges that allow an ultra-high vacuum seal to be maintained at all times.
Results
The primary test that was conducted was a vacuum test where the system was taken down to 1.3e-7 torr, where, using a residual gas analyser, we pumped helium around possible leak points with no leaks detected.
The primary test that was conducted was a vacuum test where the system was taken down to 1.3e-7 torr, where, using a residual gas analyser, we pumped helium around possible leak points with no leaks detected.
Vacuum Setup
Residual Gas Analyser Results
Final Presentation
Poster
Page updated
Report abuse