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Abstract A set of nozzle equipment for proton therapy is currently under development at China Institute of Atomic Energy (CIAE). To facilitate the off-line commissioning of the whole equipment, a set of ionization chamber signal generation system, known as the test electronics, was designed. The results showed that the system can simulate the beam position, beam fluence (which exhibits a positive correlation with the dose), and other related analog signals generated by the proton beam when it traverses the ionization chamber. Moreover, the accuracy of the simulated beam position is within ± 0.33 mm, and the accuracy of the simulated beam fluence signal is within ± 1%. The test electronics can output analog signals representing environmental parameters. The test electronics meets the design requirements, which can be used for the commissioning of the nozzle system as well as the treatment control system without the presence of the proton beam.

A set of nozzle equipment for proton therapy is currently under development at China Institute of Atomic Energy (CIAE). To facilitate the off-line commissioning of the whole equipment, a set of ionization chamber signal generation system, known as the test electronics, was designed. The results showed that the system can simulate the beam position, beam fluence (which exhibits a positive correlation with the dose), and other related analog signals generated by the proton beam when it traverses the ionization chamber. Moreover, the accuracy of the simulated beam position is within ± 0.33 mm, and the accuracy of the simulated beam fluence signal is within ± 1%. The test electronics can output analog signals representing environmental parameters. The test electronics meets the design requirements, which can be used for the commissioning of the nozzle system as well as the treatment control system without the presence of the proton beam. [ABSTRACT FROM AUTHOR]

In view of the problem that the measurement equation and transfer function of the traditional closed loop decoding algorithm are easy to cause steady state errors during acceleration, an improved closed - loop decoding algorithm is proposed in this study. Before the closed loop solution, the least square method is used to fit the output signal parameters of the rotating transformer to obtain a more accurate signal of the rotating transformer. The calibration device is designed to avoid the influence of parameter fluctuation and nonlinear factors on the system performance and enhance the stability of the system. The steady state error, angular position error and angular velocity error of the decoding algorithm are analyzed by simulation experiment. The results show that the improved closed - loop decoding algorithm is more stable and the steady state error is smaller. Angular position error fluctuation from (10,0) to (-4.0,3.5), the angular velocity error fluctuation from (-0.50, -0.25) to (-0.15,0.10). [ABSTRACT FROM AUTHOR]

Position signal faces several weak oscillations due to mechanical flaw and faults occurred in the systems. These oscillations can be identified by the encoders that determine the performance and health condition of the machine. Nevertheless, also the concerned oscillation, rotary encoder signal also includes some measurement noise and a significant trend. These trends are typically of several orders, greater in activities than the involved amplitude oscillations, making it tough to detect the small oscillations except deformation of the signal. In addition, the oscillations can be problematic, and magnitude adjusted in unstable conditions. Singular spectrum analysis (SSA) is proposed to overcome this issue. A numerical emulation is demonstrated to show the efficiency of the approach. It indicates that SSA outperforms ensemble empirical mode decomposition (EEMD), empirical mode decomposition, and complete EEMD with adaptive noise in ability and accuracy. Moreover, during the movement of the robotic arm, encoder signals from the robot are analysed to determine the sources of oscillations in joints. The suggested technique is proven to be reliable and feasible for an industrial robot. [ABSTRACT FROM AUTHOR]

Previous experiments have shown that the activity of cells in both areas 4 and 5 is strongly modulated in a continuously-graded manner for movements of the arm in 8 different directions away from a central starting position. However, it is reported here that there is a clear difference between these two areas during postural fixation of the arm in one position against loads applied in 8 different directions. Area 4 cell activity shows large variations when the monkey holds its arm at the central position by exerting forces in different directions to counteract the loads. The activity of cells in area 5 is much less strongly modulated under the same isometric conditions. These observations suggest that cell activity in area 5 is less related to the level and pattern of force output than are cells in area 4. Area 5 may produce instead a signal related more to the limb position, per se, during actively maintained posture. [ABSTRACT FROM AUTHOR]

A virtual Hall method for sensorless control of interior permanent magnet synchronous motors (IPMSMs) using high‐frequency signal injection is presented. Based on the idea of virtual Hall, the position signal is easily estimated by comparing the magnitudes of three‐phase inductances. The experimental results prove that the proposed method has good heavy‐load operation capability with a brief control structure. [ABSTRACT FROM AUTHOR]