With the continuous exploration of the universe and astronomy’s development, the telescopes are bigger and bigger. Horizon structure is widely used in the modern large telescopes rack, which carries dozens, even thousands of tons of the rotary parts and demands high accuracy and good stability. Therefore, it is one of the key technologies for large telescope to develop the precision support technology integrated direct drive with large load, high stiffness, low friction, even frictionless. Magnetic suspension bearing has not only the advantage of non-contact, no friction, high rigidity, high precision, low power, low mechanical assembly requirements, but also is integrated with the driven torque motor, which simplifies the structure, reduces the cost. This paper explores one kind of active bias magnetic suspension bearing integrated with direct drive technology based on multidisciplinary design optimization (MDO), which provides a new choice and view for the modern large astronomical telescope tracking system.
Proc. SPIE. 9150, Modeling, Systems Engineering, and Project Management for Astronomy VI
KEYWORDS: Telescopes, Astronomy, Control systems, Computer programming, Signal processing, Astronomical telescopes, Field effect transistors, Large telescopes, Optical instrument design, Control systems design
The mount drive control is the key technique which mostly affects astronomical telescope’s resolution and its speed.
However, the ultra -lower speed and the giant moment of inertia make it very difficult to be controlled. In this paper, one
segmented permanent-magnet synchronous motor (PMSM), 4m diameter, is suggested for the mount driving. A method
is presented to drive the motor directly, which is based on TMS320F28XX and Insulated Gate Bipolar Transistor (IGBT) ,
also, HEIDENHAIN tape is used to detect the absolute position of the motor together with the Hall sensor. The
segmented PMSM can work stable and the mount drive can realize nice tracking performance at ultra -lower speed with
this drive system.
The modern large telescope is endowed with advanced imaging systems and active optics, resulting in very high
peak angular resolution. The drive systems for the telescope must consequently be able to guarantee a tracking accuracy
better than the telescope angular resolution, in spite of unbalanced and sudden loads such as wind gusts and in spite of a
structure that, because of its size, can not be infinitely stiff, which puts forward a great challenge to the telescope' drive
system. Modern telescope's drive system is complicated, which performance and reliability directly affect the telescope
tracking performance and reliability. Redundant technology is one of the effective ways to improve the security of the
system. This paper will introduce one redundant synchronous control method for direct drive torque motor of large
diameter telescope drive system, which can effectively improve the telescope drive system tracking precision and
improve the reliability, stability and anti-jamming ability.
Proc. SPIE. 8450, Modern Technologies in Space- and Ground-based Telescopes and Instrumentation II
KEYWORDS: Telescopes, Control systems, Space telescopes, Astronomical telescopes, Servomechanisms, Large telescopes, Astronomical imaging, Optical instrument design, Electromagnetism, Control systems design
The direct drive motor of large aperture telescope, integrated with the telescope mechanic structure, has characteristics of
high load torque and large moment of inertia. The control method of drive system should be specially designed for the
heavy load. This article aims to list the key issues of engineering technology applied to large aperture telescope. Drive
control architecture and method, as well as design requirements of segmented direct drive motor on large astronomic
telescope, are discussed in this article.
Control network of active surface using Precise Time Protocol operates the actuators. PTP network structure, principle of
synchronization and model of clock servo are elaborated. The protocol stack with PTP is running on Actuator controller.
This scheme is used to real-time control in active surface of radio telescope.
Direct drive technology is the key to solute future 30-m and larger telescope motion system to guarantee a very high
tracking accuracy, in spite of unbalanced and sudden loads such as wind gusts and in spite of a structure that, because of
its size, can not be infinitely stiff. However, this requires the design and realization of unusually large torque motor that
the torque slew rate must be extremely steep too. A conventional torque motor design appears inadequate. This paper
explores one redundant unit permanent magnet synchronous motor and its simulation bed for 30-m class telescope.
Because its drive system is one high integrated electromechanical system, one complexly electromechanical design
method is adopted to improve the efficiency, reliability and quality of the system during the design and manufacture
circle. This paper discusses the design and control of the precise tracking simulation bed in detail.