Open AccessArticle Study on Coordinated Servo Control Between Observatory Dome and Telescope 1 Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China 2 University of Chinese Academy of Sciences, Beijing 100049, China * Author to whom correspondence should be addressed. Appl. Sci. 2026, 16(12), 5749; https://doi.org/10.3390/app16125749 (registering DOI) Submission received: 5 May 2026 / Revised: 30 May 2026 / Accepted: 4 June 2026 / Published: 8 June 2026 The higher the rotational speed of the telescope dome, the greater the vibration and noise are induced, which results in a more significant impact on telescope imaging performance, while also requiring greater driving power and increasing the control complexity. Therefore, this paper primarily focuses on appropriately reducing the dome speed during high-speed space target tracking without affecting observation effectiveness. First, the initial tolerance of the dome opening in the telescope’s horizontal state is introduced, and the variation pattern of the initial tolerance with the telescope’s elevation angle is derived; then, the angular velocity relationship between the dome and the telescope is established, and the rotational trajectory of the dome is replanned. Taking the International Space Station as an example for simulation, the results show that the maximum velocity of the dome is reduced by 25.4% compared with that of the telescope, with no field-of-view obscuration during the entire observation process. Finally, a multi-motor servo control system for the dome is designed, and practical tests demonstrate that during synchronous tracking with the telescope, the synchronization error PV of all motors is less than 2.5%, the dome tracking accuracy is better than 60″, and the maximum dome speed is reduced by approximately 33.3% compared with the telescope. This research is of great significance for appropriately reducing the dome speed requirement, alleviating high-speed vibration and noise, and simplifying control difficulty in high-speed tracking. Keywords: dome; tolerance; secant compensation; synchronous; servo control When a telescope tracks different targets, its rotational speed varies accordingly [ 6]. For medium-to-high orbit or celestial targets, the telescope moves at a low speed, and the dome can follow smoothly at an extremely low speed. However, when tracking low-orbit the telescope’s speed rises rapidly. Nevertheless, as a system characterized by high inertia and significant time delay, the dome is difficult to achieve high-speed tracking. Meanwhile, higher dome speed induces greater vibration and noise during operation. Therefore, realizing high-speed synchronization between the dome and the telescope constitutes a challenging technical issue. In dome servo control strategies, Bei Zhang et al. designed an active disturbance rejection controller to suppress the effects of large inertia and nonlinear friction, achieving a dome positioning accuracy of 1′ [ 10]. Guanjun Zhang et al. implemented automated dome control based on the ASCOM protocol and PLC [ 11]. Jörg Weingrill et al. developed a dome servo system with an independent PLC and EtherCAT bus, and accomplished reliable command interaction through ADS over TCP/IP to achieve stable synchronous motion between the dome and telescope [ 12]. Yun Li et al. proposed a method based on time synchronization and a multi-closed-loop servo architecture. By pre-packaging and sending target positions combined with millisecond-level clock synchronization, this method significantly improves the tracking accuracy, communication robustness, and fault tolerance of large-aperture telescope servo systems. This approach can also be applied to the synchronization control between the dome and the telescope [ 13 Although existing studies have greatly improved dome positioning accuracy, tracking performance, and automation, nearly all methods rely on the ideal assumption that the dome and telescope move at the same speed. They lack quantitative geometric constraints that relate telescope elevation to dome speed, and cannot solve the unobstructed synchronization problem when the maximum dome speed is lower than the telescope’s speed. This paper therefore focuses on the synchronization failure caused by insufficient dome speed during high-speed target tracking. To address the above problems, this paper proposes a coordinated dome-telescope control method based on geometric constraints and piecewise kinematic planning. First, through geometric analysis, we derive the secant constraint relationship between the dome angular velocity and the telescope elevation angle, which provides a theoretical basis for subsequent speed planning. Second, we overcome the engineering limitation that the maximum dome speed is lower than the maximum telescope speed. Without any hardware modification, and using only trajectory planning, we achieve obstruction-free synchronization throughout the entire motion even when the maximum dome speed is less than the maximum telescope speed, significantly reducing the performance requirements for the dome drive system. Finally, through a three-phase speed planning strategy, we present a complete analytical expression for the dome speed. This analytical solution is computationally simple, real-time capable, and effective, meeting the stringent requirements of astronomical observations. 2. Tolerance of Dome Window 2.1. Initial Tolerance Large telescope domes typically adopt massive steel truss structures, which cause significant difficulties in rapid start-up and braking. When the control system receives the azimuth rotation signal from the telescope, the dome’s large inertia inevitably introduces a noticeable response delay. Meanwhile, factors such as potential slippage or backlash in the driving mechanism may cause the actual position of the dome to lag behind the desired position of the telescope. Therefore, in dome design, the size of the observation window is usually set larger than the minimum required by the telescope’s field of view, leaving a certain margin, as implemented in the LSST dome. This margin is referred to as the “initial tolerance” in this study, as illustrated in . The initial tolerance δ 0 is: δ 0 = tan − 1 D d o m e − D t e l 2 L − ∅ (1) The telescope is at an elevation angle of 0°, and its pointing direction is aligned with the center of the dome aperture. The relevant parameters are defined as follows: the aperture diameter of the telescope is D t e l , its field of view angle is 2 ∅ , the width of the dome aperture is D d o m e , and the distance from the telescope center to the outer edge of the dome aperture is L . 2.2. Secant Variation of Tolerance The azimuth angle of the telescope does not have a one-to-one correspondence with the spatial angle of its observed target. Instead, it exhibits a secant variation with the telescope’s elevation angle. a shows the target trajectory in the celestial coordinate system, while b shows the target’s horizontal motion trajectory in the plane coordinate system, where SS1 represents the target trajectory. In addition, S ′ S 1 ′ denotes its projection on the ground, θ and E represent the azimuth angle and elevation angle of the telescope, respectively, and θ ′ denotes the target spatial angle. According to the law of sines for triangles, we can obtain: sin θ ′ = S S 1 O S sin θ = S ′ S 1 ′ O S ′ cos E = O S ′ O S S S ′ = S ′ S 1 ′ (2) Thus, it can be obtained that: sin θ = S ′ S 1 ′ O S ′ = S ′ S 1 ′ OS ⋅ cos E = sin θ ′ cos E (3) According to the differential theorem, within an extremely short time interval: θ = θ ′ cos E = θ ′ ⋅ sec E (4) Thus, it can be concluded that the spatial angle and the planar angle exhibit a secant relationship, so the tolerance also satisfies the secant relationship, namely: δ ′ = δ 0 cos E = δ 0 ⋅ sec E (5) 3. Dome Trajectory Planning During the synchronous tracking process of the dome and the telescope, assuming that V D ome m a x ∇ δ ′ ∇ δ ′ , a T e l e s c o p e t ≤ ∇ δ ′ (11) where a T e l e s c o p e t denotes the telescope acceleration, and ∇ δ ′ represents the tolerance variation rate. This section derives the velocity relationship between the telescope and the dome under the condition that the rotational speed of the telescope exceeds the maximum rotational velocity of the dome, and calculates for the dome’s rotational velocity in each of the three stages. Based on the derivation results, the rotational trajectory of the dome is replanned, which is of considerable significance for realizing high-speed synchronization between the telescope and the dome while the latter operates at a lower dome speed. 4. Simulation This section conducts simulation verification based on the foregoing analysis and calculations to validate the feasibility and rationality of the proposed theory. The International Space Station (ISS) is selected as the simulation target: The ISS is a low-Earth-orbit satellite whose angular velocity during an overpass can exceed 10°/s, much higher than that of typical astronomical targets. This allows an extreme test of the proposed synchronization strategy under the condition where the dome speed is limited. Moreover, its orbital parameters are publicly available and accurate, facilitating simulation modeling. To simulate the high-speed tracking scenario, the position of the telescope site is randomly adjusted to ensure the target pass through the zenith at a relatively high speed. The target begins to accelerate when the telescope elevation angle reaches 82.4625°, with the elevation angle increasing gradually. When the elevation angle reaches 86.0665°, the azimuth rotational speed of the telescope reaches a peak of 14.7504°/s. Subsequently, as the target’s elevation angle descends, the telescope’s azimuth speed declines accordingly until the observation concludes. Partial trajectory data are excerpted as shown in , and the dome velocity synchronization computation is carried out based on these orbital data. The dome velocity at each stage is solved using the enumeration method based on Equations (6)–(11). Calculations show that when V D o m e m a x ≥ 10.6825 ° / s , the dome can avoid obstructing the target throughout the entire tracking process by employing an appropriate control strategy. The maximum velocity of the dome is reduced by 27.5% compared with that of the telescope, which is of great significance for motion control and structural safety of large-scale telescope domes. In practical real-time tracking applications, this value is slightly increased to account for the influence of wind disturbances during operation. For a more intuitive comparison, the actual alignment errors of the dome at a maximum speed of 10°/s and 11°/s was analyzed and compared, as listed in , the time unit in the table is seconds, and numerical differencing will be performed in actual operation with a sampling interval of 0.01 s. It can be observed that when the maximum speed of the dome is 10°/s, corresponding to the period from the 9th second to the 12th second in the table, the actual alignment error between the dome and the telescope exceeds the corresponding maximum tolerance at this time, resulting in obstruction to the telescope observation; In contrast, when the maximum speed of the dome is set to 11°/s, the telescope can maintain normal operation throughout the tracking process, and the maximum velocity of the dome is reduced by 25.4% compared with that of the telescope. shows the velocity curves of the dome and the telescope, and presents the variation curves of the pointing error between them as well as the allowable tolerance. It can be observed that when the maximum dome velocity is set to 11°/s, the pointing error remains below the corresponding tolerance at all times and always lies within the tolerance envelope. In contrast, when the maximum dome velocity is limited to 10°/s, the pointing error evidently exceeds the tolerance envelope. At this moment, the maximum telescope velocity reaches 14.7504°/s, which is significantly higher than the maximum velocity of the dome. 5. Design of Servo Control System The dome motion described in this paper adopts a feedforward control strategy based on the desired trajectory and system model. In the actual tracking process, the dome and telescope are inevitably affected by wind loads, temperature variations, and modeling uncertainties. Meanwhile, the positioning accuracy and tracking error of the dome also influence its pointing accuracy relative to the telescope. Therefore, closed-loop position correction must be applied during operation. The servo control system is briefly introduced in the following. 5.1. Drive Scheme In this paper, a brushless torque motor is selected as the driving motor due to its strong dynamic response capability and high positioning accuracy. Such motors feature a wide speed range, rapid dynamic response, and high positioning precision. To ensure that the dome achieves a high dynamic response performance, a synchronous drive scheme employing seven motors is adopted. The transmission system utilizes gear transmission, which offers obvious advantages: first, the fixed transmission ratio allows accurate positioning; second, the rigid contact enables the transmission of large torques. This drive scheme can match the high-speed operation of the telescope and meet the tracking and measurement requirements of high-speed targets. 5.2. Position Measurement Two methods are used to measure the dome position: a built-in encoder integrated into the drive motor and an independently mounted grating angular encoder. The former indirectly obtains the dome rotational position from the motor speed and the gear reducer. Since the dome is driven by multiple motors, slight discrepancies exist among individual drives. Therefore, this method is mainly used to achieve synchronous speed control of multiple motors. The latter can directly measure the absolute angular position of the dome and match the telescope angle in a 1:1 manner. During the tracking process of the dome and telescope, to reduce system fluctuations caused by external disturbances, real-time correction of the angular error between them is required. The error value should be less than the allowable angular tolerance, as expressed in Equation (12). It should be noted that the tolerance here is not a fixed value, but is related to the telescope’s pitch angle, which also serves as the core indicator for feedback control. ∆ = θ T e l e s c o p e − θ D o m e ≤ δ ′ = δ 0 ⋅ sec E (12) 5.3. Servo Control Structure Servo Design Results The control loop of the servo control system adopts the traditional proportional-integral-derivative (PID) control method, which consists of three closed loops: position loop, speed loop, and current loop, with their specific structure and signal transmission relationship illustrated in . The three loops cooperate with each other to form a hierarchical control architecture, where the position loop is responsible for accurate positioning of the dome, the speed loop guarantees stable operation of the drive motors, and the current loop effectively suppresses current fluctuations to protect the motor and improve control responsiveness. To achieve high-precision synchronous operation of the multi-motor drive system, the tracking control system adopts a multi-motor speed synchronization control scheme, in which the seven drive motors are divided into a master-slave control structure for unified management. Specifically, one motor is designated as the master motor, which receives the speed command from the upper-level control system and serves as the reference for speed synchronization. The remaining six motors act as slave motors, which detect the output speed of the master motor in real time and adjust their own operating speed through the PID control loop to keep pace with the master motor. This master-slave synchronization control mode not only ensures the consistency of the rotational speed of all motors but also effectively reduces the influence of individual motor differences on the overall drive performance, laying a solid foundation for stable and accurate tracking of the dome. Synchronous control strategy: The main control computer calculates the dome velocity information in advance based on the observed target orbit data and generates servo control instructions. During observation, the main control computer sends control commands for both the telescope and the dome, enabling them to run synchronously. The position information of the telescope is fed back to the dome control system to verify the position difference between the two, and perform dynamic correction. The control block diagram is shown in . 5.4. Servo Design Results Based on the dome synchronous control system, an integrated simulation model is established to simulate its dynamic response. The positioning accuracy of the dome is within 20 arcseconds, as shown in a, which is considerably smaller than the initial opening tolerance δ 0 of the dome. Then, a sinusoidal position command is applied to both the dome and the telescope with a maximum velocity of 10°/s. Under this condition, the maximum tracking error between them is approximately 49.3 arcseconds, as shown in b. Both the positioning accuracy and tracking accuracy are smaller than the corresponding tolerance variation of the dome, ensuring that normal observation is not affected during high-speed rotation. 6. Result of Test To verify the rationality of the above theory, a test was conducted on the dome. The dome has a rotational diameter of approximately 16 m, a height of about 12 m, and a weight of roughly 75 t. It is driven by seven sets of AC permanent magnet synchronous servo motors, with the drive system parameters listed in . The current control system employs closed-loop control for position, speed, and current. Speed measurement is performed on the motor shaft, while the dome position information is provided by a multi-turn encoder fixed on the enclosure wall. The actual rotational speed of the dome can be calculated from the position information. The dome is rotationally controlled by seven motors. The speed is taken as the average value of all motors, with a maximum speed of 7200°/s. show the multi-motor synchronous step response and multi-motor sinusoidal tracking response, respectively. The synchronous speed error of each motor is less than 2.5%. The dynamic error is defined as the deviation between the actual operating speed of the dome and the theoretically planned speed. The root mean square (RMS) is adopted as the quantitative indicator, and the formula is given in Equation (13): e r m s = 1 N ∑ i = 1 N v r e f i − v a c t i 2 (13) where v r e f i is the theoretical speed value at the i-th sampling instant, generated in real time by the dome trajectory planning algorithm proposed in Section 3; v a c t i is the actual speed value at the same instant, obtained from the feedback of an optoelectronic encoder mounted on the dome drive shaft; and N is the total number of sampling points within the test period. The sampling frequency is 100 Hz, and the test duration covers the complete motion cycle of the dome. The actual speed of the dome is measured by an encoder, and a sinusoidal reference tracking scheme is adopted. shows the sinusoidal tracking response of the dome, where the maximum rotational speed of the dome is 8°/s, and the maximum error during operation is less than 60 arcseconds. This value is far smaller than the initial opening tolerance of the dome, thus satisfying the synchronous control requirements between the dome and the telescope. 7. Discussion The dome speed matching method proposed in this paper, based on the secant constraint and three-phase planning, derives its core advantages from the analytical modeling of geometric constraints and targeted handling of speed-limited engineering conditions. Conventional servo control typically requires the dome and telescope to operate at equal speeds, or at least that the dome speed is not lower than the telescope speed. However, for large-scale domes, factors such as drive power, moment of inertia, and speed limitations often make meeting this requirement entail high hardware costs. By establishing the secant constraint relationship between the dome angular velocity and the telescope elevation angle, and designing a three-phase speed planning strategy (constant-acceleration chase, speed matching, and deceleration adjustment), this paper fundamentally removes the engineering bottleneck that “the dome speed must not be lower than the telescope speed.” In the simulation, the maximum dome speed (11°/s) is only 74.6% of the maximum telescope speed (14.7504°/s); in the actual test, the maximum dome speed (8°/s) is 66.3% of the maximum telescope speed (12.08°/s). In both cases, obstruction-free synchronization is achieved throughout the entire motion. This demonstrates that the proposed method imposes significantly lower performance requirements on the dome drive system compared to conventional approaches. To further evaluate the advantages of the proposed method, we compare it with three representative studies from both domestic and international sources, as shown in . As shown in , most existing methods are based on the equal-speed assumption or only achieve dome opening/closing decisions. Although J. DeVries et al. performed trajectory planning for the LSST dome, their method is only applicable to long-exposure quasi-static target observations and does not systematically solve the obstruction-free synchronization problem when the maximum dome speed is lower than the maximum telescope speed [ 24]. By introducing the secant constraint between the elevation angle and the dome speed, and designing a three-phase planning strategy, this paper fills this gap. In the actual test, the dome speed is reduced by approximately 33.3%. This demonstrates that the proposed method can significantly lower the performance requirements for the dome drive system, thereby reducing hardware costs, decreasing operational energy consumption, and improving mechanical operational safety. This study not only solves the technical challenges of dome-telescope coordinated control, but also has clear scientific significance and social value. At the scientific level, the proposed high-precision tracking and fast-response strategy can support observations of high-energy transient phenomena such as gravitational wave optical counterparts and gamma-ray burst afterglows, thereby providing key technical support for research in particle physics and astroparticle physics. At the application level, the proposed control strategy can be extended to space debris monitoring and low-Earth-orbit satellite tracking, serving space security and space situational awareness, with potential for cross-disciplinary technology spillover. The dome trajectory planning method proposed in this paper is realized based on the tolerance secant variation, and a detailed multi-motor parallel servo control system is designed. The method is simple, effective, and practical, and is feasible for any dynamic target tracking process, particularly for fast tracking. Nevertheless, it has certain limitations: the orbit of the observed target must be known in advance; otherwise, trajectory planning is difficult to perform. As can be seen from the above discussion, the telescope is initially aligned with the center of the dome aperture. In future work, full use will be made of the left-right symmetry of the tolerance, allowing the telescope to align with the edge of the dome aperture. This will further expand the tolerance range and further reduce the maximum dome speed. However, it will also complicate trajectory planning, as the dome may experience forward and reverse rotation, frequent start-stop, and direction switching, which increases the complexity of servo control. This paper addresses the coordinated servo control problem of an observatory dome and telescope, and proposes a method based on geometric constraints and piecewise kinematic planning. First, through geometric analysis, a secant constraint relationship between the dome angular velocity and the telescope elevation angle is established, revealing the dynamic coupling mechanism between the two beyond pure azimuth following. Second, a three-phase speed planning strategy is designed. Without increasing hardware cost, this trajectory planning strategy achieves obstruction-free synchronization under the condition that the maximum dome speed is lower than the maximum telescope speed. Third, a closed-form analytical expression for the dome speed profile is derived. This analytical solution has clear physical meaning and simple computation, making it convenient for direct implementation in control systems. Finally, validation is carried out through simulation and actual measurement. In the simulation, the telescope maximum speed is 14.7504°/s and the dome maximum speed is 11°/s, resulting in a reduction in the maximum dome speed by approximately 25.4% compared with the telescope. In the actual measurement, the telescope maximum speed is 12.08°/s and the dome maximum speed is 8°/s, giving a reduction of approximately 33.3%. The results show that even when the maximum dome speed is significantly lower than the maximum telescope speed, the proposed method effectively eliminates field-of-view obstruction and meets observation requirements. Compared with existing approaches that rely on iterative optimization or intelligent algorithms, our method is easier to deploy in engineering practice and is particularly suitable for astronomical observation scenarios that demand high real-time performance and reliability. Author Contributions Conceptualization, W.W. and J.W.; methodology, W.W.; software, W.W. and L.S.; validation, W.W., J.W., Z.W., M.S. and L.S.; formal analysis, W.W.; investigation, W.W.; resources, W.W.; data curation, W.W. and M.S.; writing—original draft preparation, W.W.; writing—review and editing, W.W.; visualization, W.W.; supervision, W.W.; project administration, W.W.; funding acquisition, J.W. All authors have read and agreed to the published version of the manuscript. Funding This research was funded by the Jilin Province Science and Technology Development Plan (NO. 20230203113SF). Institutional Review Board Statement Not applicable. Informed Consent Statement Not applicable. 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Actual alignment error and tolerance variation curve at different maximum speeds. Actual alignment error and tolerance variation curve at different maximum speeds. Block diagram of PID control loop. Block diagram of PID control loop. Dome-Telescope Synchronous Control Block Diagram. Dome-Telescope Synchronous Control Block Diagram. ( a) Dome positioning accuracy; ( b) Dome tracking accuracy. ( a) Dome positioning accuracy; ( b) Dome tracking accuracy. Multi-motor synchronous step response: ( a) Step response; ( b) Speed errors. Multi-motor synchronous step response: ( a) Step response; ( b) Speed errors. Multi-motor synchronous sinusoidal tracking response: ( a) sinusoidal tracking response; ( b) Speed errors. Multi-motor synchronous sinusoidal tracking response: ( a) sinusoidal tracking response; ( b) Speed errors. Dome sinusoidal tracking response: ( a) Sinusoidal tracking response; ( b) Tracking errors. Dome sinusoidal tracking response: ( a) Sinusoidal tracking response; ( b) Tracking errors. Target elevation angle curve. Target elevation angle curve. Dome-telescope synchronous performance, in red the tolerance variation, in yellow the telescope speed, in blue the dome speed, in green the actual error between dome and telescope. Dome-telescope synchronous performance, in red the tolerance variation, in yellow the telescope speed, in blue the dome speed, in green the actual error between dome and telescope. Comparison of Alignment Errors Between Dome and Telescope. Comparison of Alignment Errors Between Dome and Telescope. Initial Tolerance δ = 1° Maximum Speed of Dome = 11°/s Maximum Speed of Dome = 10°/s Tolerance Variation Time Azimuth Elevation Azimuthal Velocity Dome Speed Actual Error Dome Speed Actual Error δ ′ = δ 0 ⋅ sec E 1 201.5694 82.4625 3.5179 3.5179 0 3.5179 0 7.6234 2 197.1464 83.2965 4.4230 4.4230 0 4.4230 0 8.5667 3 191.4976 84.0821 5.6488 5.6488 0 5.6488 0 9.6990 4 184.2016 84.7953 7.2960 7.2960 0 7.2960 0 11.0236 5 174.7853 85.4004 9.4163 9.4163 0 9.4163 0 12.4701 6 162.9395 85.8481 11.8458 11 0.8458 10 1.8458 13.8120 7 148.9824 86.0831 13.9571 11 3.8028 10 5.8028 14.6392 8 134.2320 86.0665 14.7504 11 7.5533 10 10.5584 14.5776 9 120.4949 85.8014 13.7371 11 10.2904 10 14.2995 13.6586 10 108.9635 85.3305 11.5314 11 10.8218 10 15.8269 12.2838 11 99.8452 84.7094 9.1183 11 8.9401 10 14.9452 10.8451 12 92.7883 83.9855 7.0569 8.9386 7.0584 10 12.0021 9.54379 13 87.3192 83.1930 5.4691 7.3508 5.1767 8 7.4712 8.4370 14 83.0288 82.3545 4.2904 6.1721 3.295 6 5.7616 7.5163 15 79.6092 81.4853 3.4196 5.3013 1.4133 4 5.1812 6.7539 16 76.8382 80.5955 2.7710 4.6527 −0.4684 4 3.9522 6.1198 17 74.5572 79.6922 2.2810 2.281 −0.4684 4 2.2332 5.5886 18 72.6527 78.7801 1.9045 1.9045 −0.4684 3 1.1377 5.1394 19 71.0419 77.8631 1.6108 1.6108 −0.4684 2 0.7486 4.7563 20 69.6640 76.9439 1.3779 1.3779 −0.4684 2 0.1264 4.4266 Driver component parameters. Driver component parameters. Model Rated Speed Rated Torque Rated Power Rated Current Number of Motors 31330A 2000 r/min 180 N·m 38 KW 74 A 7 Comparison of the proposed method with representative dome control approaches. Comparison of the proposed method with representative dome control approaches. Method Source Technical Approach Main Advantage Main Limitation Ref. J. DeVries et al. (2016) Nonequal speed trajectory planning Suitable for long exposure observations Not applicable to fast dynamic targets [ 15] Zhang Bei et al. (2016) ADRC + equal speed assumption Overcomes inertia/friction, 1′ positioning accuracy Does not address speed limited synchronization [ 10] Castellón et al. (2022) Fuzzy logic control Autonomous opening/closing, adapts to weather Requires weather station and all sky camera [ 22] Proposed method Secant compensation + three phase planning Obstruction free synchronization under speed limited condition Requires prior orbit data / Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content. © 2026 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license. Share and Cite MDPI and ACS Style Wang, W.; Wang, J.; Wang, Z.; Shao, M.; Song, L. Study on Coordinated Servo Control Between Observatory Dome and Telescope. Appl. Sci. 2026, 16, 5749. https://doi.org/10.3390/app16125749 AMA Style Wang W, Wang J, Wang Z, Shao M, Song L. Study on Coordinated Servo Control Between Observatory Dome and Telescope. Applied Sciences. 2026; 16(12):5749. https://doi.org/10.3390/app16125749 Chicago/Turabian Style Wang, Wenpan, Jianli Wang, Zhichen Wang, Meng Shao, and Liduo Song. 2026. "Study on Coordinated Servo Control Between Observatory Dome and Telescope" Applied Sciences 16, no. 12: 5749. https://doi.org/10.3390/app16125749 APA Style Wang, W., Wang, J., Wang, Z., Shao, M., & Song, L. (2026). Study on Coordinated Servo Control Between Observatory Dome and Telescope. Applied Sciences, 16(12), 5749. https://doi.org/10.3390/app16125749 Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here. Article Metrics Article metric data becomes available approximately 24 hours after publication online.
