CYCLOTRONS2022 - List of Authors (Guo, Q.K.)

Paper	Title	Page
MOPO001	A Real-Time Controller for Rapid Energy Degrading of the CYCIAE-230 Cyclotron Beam Production System	47
	Q.Q. Song, H.R. Cai, Q.K. Guo, A.L. He, T.Y. Jiang, Y. Wang, Z.G. Yin, T.J. Zhang, B.H. Zhao CIAE, Beijing, People’s Republic of China
	The energy selection system (ESS) plays an important role in a proton therapy system. Usually, it consists of an energy degrader, a set of achromatic bending magnets, an envelope collimator, and a momentum-selecting slit. In CIAE, a dedicated beam transportation line, including these essential elements, for the CYCIAE-230 superconducting cyclotron has been designed and manufactured for study purposes. To reduce the layer switching time, e.g. typically within 50 milliseconds, this ESS system takes advantage of VME-based real-time controller design. On one side, this controller uses S-curve to direct drive the step motors of various actuators, this is done by an off-the-shelf embedded controller. On the other hand, it uses Data Distribution Service (DDS) communication protocol to tap into the nozzle control system network directly. In such a manner, the energy requirement can be efficiently handled and the controller is also responsible for the current regulation of the 46 magnets. The design of this high-efficiency controller will be reported in this paper, both from hardware and software aspects. Preliminary test results will also be evaluated and analyzed to direct further improvement of the system.
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO001
About •	Received ※ 20 October 2022 — Revised ※ 27 January 2023 — Accepted ※ 30 January 2023 — Issue date ※ 10 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPO019	Optimization of Rapid Magnetic Field Control of the CYCIAE-230 Cyclotron Beamline Magnets	106
	A.L. He, H.R. Cai, Q.K. Guo, P. Huang, Q.Q. Song, Y. Wang, Z.G. Yin, T.J. Zhang, B.H. Zhao CIAE, Beijing, People’s Republic of China
	The magnetic field precise and rapid control of the beamline magnets is essential to the Energy Selection System (ESS) for the proton therapy facility. During the scanning of proton beam for therapy, the field of each beamline magnet should be precisely controlled within the set time, layer upon layer. The position of beam spot to the nozzle should undoubtedly be stable and unchanged during the process. In practice, however, due to the wide energy range of proton therapy (70 MeV-230 MeV), the dynamic response of the beamline magnets usually shows nonlinear performances at a different energy, e.g., the magnetic field may cause a significant overshoot for some specific beam energy if one ignores the nonlinear effect. More challenge is that the magnetic field drops too slowly between the energy steps, which compromises the overall performance of rapid intensity modulated scanning therapy. A dynamic PID parameter optimization method is reported in this paper to address this issue. According to the transfer function of each magnet, the entire energy range is divided into several steps. Then, the experiments are carried out to find the most suitable PID parameters for each energy step. Finally, the "beam energy - excitation current-PID parameters" lookup table (LUT) is generated and stored in the beamline control system BCS for automation. During the treatment, using the LUT allows the energy setting for beamline magnets to be adjusted automatically with the most appropriate PID parameter, guaranteeing the overall performance of rapid scanning therapy. The experimental results show the overall response time of all the beamline magnets reduced from several hundred milliseconds to less than 65 ms, which meets the design requirement of less than 80ms.
	Poster MOPO019 [0.364 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO019
About •	Received ※ 06 January 2023 — Revised ※ 30 January 2023 — Accepted ※ 01 February 2023 — Issue date ※ 10 February 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

A Real-Time Controller for Rapid Energy Degrading of the CYCIAE-230 Cyclotron Beam Production System

47

Q.Q. Song, H.R. Cai, Q.K. Guo, A.L. He, T.Y. Jiang, Y. Wang, Z.G. Yin, T.J. Zhang, B.H. Zhao
CIAE, Beijing, People’s Republic of China

The energy selection system (ESS) plays an important role in a proton therapy system. Usually, it consists of an energy degrader, a set of achromatic bending magnets, an envelope collimator, and a momentum-selecting slit. In CIAE, a dedicated beam transportation line, including these essential elements, for the CYCIAE-230 superconducting cyclotron has been designed and manufactured for study purposes. To reduce the layer switching time, e.g. typically within 50 milliseconds, this ESS system takes advantage of VME-based real-time controller design. On one side, this controller uses S-curve to direct drive the step motors of various actuators, this is done by an off-the-shelf embedded controller. On the other hand, it uses Data Distribution Service (DDS) communication protocol to tap into the nozzle control system network directly. In such a manner, the energy requirement can be efficiently handled and the controller is also responsible for the current regulation of the 46 magnets. The design of this high-efficiency controller will be reported in this paper, both from hardware and software aspects. Preliminary test results will also be evaluated and analyzed to direct further improvement of the system.

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO001

About •

Received ※ 20 October 2022 — Revised ※ 27 January 2023 — Accepted ※ 30 January 2023 — Issue date ※ 10 July 2023

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPO019

Optimization of Rapid Magnetic Field Control of the CYCIAE-230 Cyclotron Beamline Magnets

106

A.L. He, H.R. Cai, Q.K. Guo, P. Huang, Q.Q. Song, Y. Wang, Z.G. Yin, T.J. Zhang, B.H. Zhao
CIAE, Beijing, People’s Republic of China

The magnetic field precise and rapid control of the beamline magnets is essential to the Energy Selection System (ESS) for the proton therapy facility. During the scanning of proton beam for therapy, the field of each beamline magnet should be precisely controlled within the set time, layer upon layer. The position of beam spot to the nozzle should undoubtedly be stable and unchanged during the process. In practice, however, due to the wide energy range of proton therapy (70 MeV-230 MeV), the dynamic response of the beamline magnets usually shows nonlinear performances at a different energy, e.g., the magnetic field may cause a significant overshoot for some specific beam energy if one ignores the nonlinear effect. More challenge is that the magnetic field drops too slowly between the energy steps, which compromises the overall performance of rapid intensity modulated scanning therapy. A dynamic PID parameter optimization method is reported in this paper to address this issue. According to the transfer function of each magnet, the entire energy range is divided into several steps. Then, the experiments are carried out to find the most suitable PID parameters for each energy step. Finally, the "beam energy - excitation current-PID parameters" lookup table (LUT) is generated and stored in the beamline control system BCS for automation. During the treatment, using the LUT allows the energy setting for beamline magnets to be adjusted automatically with the most appropriate PID parameter, guaranteeing the overall performance of rapid scanning therapy. The experimental results show the overall response time of all the beamline magnets reduced from several hundred milliseconds to less than 65 ms, which meets the design requirement of less than 80ms.

Poster MOPO019 [0.364 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO019

About •

Received ※ 06 January 2023 — Revised ※ 30 January 2023 — Accepted ※ 01 February 2023 — Issue date ※ 10 February 2023

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)