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The purpose of this paper is to propose an adaptive robust controller for coupled attitude and orbit control of rigid spacecraft based on dual quaternion in the presence of external disturbances and model uncertainties.

First, based on dual quaternion, a theoretical model of the relative motion for rigid spacecraft is introduced. Then, an adaptive robust controller which can realize coordinated control of attitude and orbit is designed in the existence of external disturbances and model uncertainties.

This paper takes advantage of the Lyapunov function which can guarantee the asymptotic stabilization of the whole system in the existence of parameters uncertainties. Simulation results show that the proposed controller is feasible and effective.

This paper proposes a coupled attitude and orbit adaptive robust controller based on dual quaternion. Simulation results demonstrate that the proposed controller can achieve higher control performance in the presence of parameters uncertainties.

Hill equations have definite limitation in the design of multiple spacecraft formation flying in eccentric orbits. To solve the problem, the design method of spacecraft formation flying in a circular reference orbit based on Hill equation can be generalized and applied to spacecraft formation flying in eccentric orbits.

In this paper, T‐H equation is expressed as the explicit function form of reference orbit true anomaly, and the state transition matrix of relative motion of spacecraft formation flying in eccentric orbits is derived. According to the requirement that relative dynamics equation of spacecraft formation flying in eccentric orbits has periodicity solution, the paper theoretically gives the initial condition needed by the long‐term close‐distance spacecraft formation flying including the relationship between relative position and relative velocity. Without perturbation the spacecraft formation, which satisfies the initial periodicity restriction, can keep long‐term close‐distance flying without the need of active control.

Based on the theoretical analysis, some numerical simulations are carried out. The results demonstrate that each spacecraft in eccentric orbits can run in a periodic motion surrounding the center spacecraft under some conditions. And spacecraft formation reconfiguration is implementing according to missions.

Combined with the periodicity restriction primary condition a new method about spacecraft formation reconfiguration is put forward. The method given by this paper can be applied to eccentric orbits of arbitrary eccentricity, and provides theoretical reference for orbit design of spacecraft formation flying in eccentric orbits.

In this paper, a coordinated attitude control law for a tracking and data relay satellite (TDRS) with mobile antennas is proposed. To track or point the target spacecraft with median/law orbit, the large mobile antennas have to move in a wide range, the movement of such mobile antennas disturbing the satellite attitude. Conventionally, the main body of the satellite and the mobile antennas are controlled independently. The proposed controller first estimates the TDRS's angular momentum which the mobile antennas will produce, based on the momentum conservation equation, then adds the estimated angular momentum as a feedforward signal to the conventional control law. The proposed controller is demonstrated using mathematical simulation, the results of which coincide well with analytical results.

To give a closed‐form solution of the relative pose determination problem based on monocular vision during final approach phase of spacecraft Rendzvous and Docking.

Based on the assumption of scaled orthographic projection, the model of perspective projection is simplified by representing the relative attitude using unit quaternion. Then a closed‐form solution is derived. Subsequently, this study correct the approximate solution to compensate the error caused by the assumption of scaled orthographic projection.

Extensive simulation studies were conducted for the validation of the proposed algorithm using Matlab™. When there are no relative attitudes between RVD spacecrafts, target distance for camera=2‐20 m. The simulation results show that the largest relative error of corrected relative position parameters is about 0.12 percent. When distance between RVD spacecrafts exceeds 5 m, the largest error of corrected relative attitude parameters are less than 0.3°. When the distance between spacecrafts are constant, the relative attitude parameters are changed, respectively, the simulition results show the largest relative error of relative position is 1 percent, and largest error of estimated relative attitude is 1.2°, when a relative attitude angle reaches 20°.

The proposed algorithm avoids the multiple results problem in determining the relative position and attitude parameters and the closed‐form solution is simple and effective, is more suitable for on‐board implementation.

In the domain of information science, affordance is a relatively new concept that deserves further exploration. It may serve as a bridge to narrow the research-practice gap that has persisted in information studies. Building upon previous research, we call for a broader concept of affordance that would help researchers understand information practices from an ecological perspective.

The study focuses on conceptualizing affordances for information practices in order to theorize engagement among people, technology, and sociocultural environments. We develop a hierarchical model and a component model to illustrate how key tenets of affordances can be linked with the decomposition of activities and its mechanism. Following this, we describe an illustrative case of a popular Chinese cloud-based music platform to demonstrate the utility of our conceptual frameworks in guiding studies of information practices.

The study proposes to shift the focus of technology affordances, which highlights the features and functions of particular technologies, to the affordances for practices that are enacted through technology and social construction within a sociocultural environment. The illustrative case of the cloud-based music platform shows that the proposed models can provide a structured view of operations, actions and motives for music information practices. The processes of internalization and externalization offer insight into the decomposition of information practice as a chain of activity-action-operation.

This study contributes to the literature on theorizing engagement among people, technology and sociocultural environments through the theoretical lens of affordances and sheds new light on the challenges of information practice.

Considering the influence of environmental noise and modeling error during the process of the robotic automatic grinding aero-engine blade, this study aims to propose a method based on the extended state observer (ESO) to reduce the fluctuation of normal grinding force.

First, the measurement range of the six-dimensional force sensor is calibrated according to the maximum acceleration of end-effector and grinding force. Second, the gravity and zero drift compensation model is built to compensate for measurement error. Finally, the switching function is designed based on the difference between the expected grinding force and the actual feedback value. When the value of function stays within the switching band, a nonlinear active disturbance rejection control (ADRC) loop is applied. When the function value reaches outside the switching band, an ESO-based sliding mode control (SMC) loop is applied.

The simulated and experimental results show that the proposed control method has higher robustness compared with proportion-integral-derivative (PID), Fuzzy PID and ADRC.

The processing parameters of this paper are obtained based on the single-factor experiment without considering the correlation between these variables. A new control strategy is proposed, which is not only used to control the grinding force of blades but also promotes the development of industrial control.

ESO is used to observe environmental interference and modeling errors of the system for real-time compensation. The segment control method consisting of ESO-based SMC and ESO-based ADRC is designed to improve the robustness. The common application of the two parts realizes suppression of fluctuation of grinding force.

Hedonic social applications have been increasingly popular among health information consumers. However, it remains unclear what motivates consumers to adopt health information in hedonic applications when they have alternative choices of more formal health information sources. Building on the self-determination theory and the affordances lens, this study aims to investigate how different affordances on hedonic social applications affect consumers' basic psychological needs and further influence their intention to adopt health information on such applications.

As TikTok demonstrated great potential in disseminating health information, we developed a model that we analyze using the PLS-SEM technique with data collected from a valid research sample of 384 respondents with health information seeking or encountering experience in TikTok.

The results suggested that health information adoption in hedonic social applications is significantly predicted by the satisfaction of consumers' basic psychological needs, namely autonomy, relatedness and competence. Moreover, the satisfaction of basic psychological needs is positively affected by affordances provided by the hedonic social applications. The hedonic affordances positively influence autonomy satisfaction, while the connective affordances positively affect relatedness satisfaction, and the utilitarian affordances positively support competence satisfaction.

The study indicates that hedonic social applications such as TikTok could be an important channel for consumers to access and adopt health information. The study contributes to the literature by proposing a theoretical model that explains consumers' health information adoption and yields practical implications for designers and service providers of hedonic social applications.

The purpose of this paper is to explore how social value orientation and domain knowledge affect cooperation levels and transcription quality in crowdsourced manuscript transcription, and contribute to the recruitment of participants in such projects in practice.

The authors conducted a quasi-experiment using Transcribe-Sheng, which is a well-known crowdsourced manuscript transcription project in China, to investigate the influences of social value orientation and domain knowledge. The experiment lasted one month and involved 60 participants. ANOVA was used to test the research hypotheses. Moreover, inverviews and thematic analyses were conducted to analyze the qualitative data in order to provide additional insights.

The analysis confirmed that in crowdsourced manuscript transcription, social value orientation has a significant effect on participants’ cooperation level and transcription quality; domain knowledge has a significant effect on participants’ transcription quality, but not on their cooperation level. The results also reveal the interactive effect of social value orientation and domain knowledge on cooperation levels and quality of transcription. The analysis of the qualitative data illustrated the influences of social value orientation and domain knowledge on crowdsourced manuscript transcription in detail.

Researchers have paid little attention to the impacts of the psychological and cognitive factors on crowdsourced manuscript transcription. This study investigated the effect of social value orientation and the combined effect of social value orientation and domain knowledge in this context. The findings shed light on crowdsourcing transcription initiatives in the cultural heritage domain and can be used to facilitate participant selection in such projects.

Although leveraging social media to access healthcare information is nothing new, a boom in short video apps offers new potential for disseminating health-related information. However, it is still unclear how short video apps might facilitate and benefit users’ consumption of health information. Furthermore, the technology features of short video apps complicate attempts to conduct research about them; as a consequence, they have been understudied. For addressing these concerns, this study adopts an affordance perspective to investigate the relationship between affordances and user experience and to examine factors that contribute to users’ intention to continue using short video apps to obtain health information.

Drawing upon affordance theory, we constructed a research model that integrates four types of affordances (livestreaming, searching, meta-voicing and recommending), three types of user experience (immersion, social presence and credibility perception), and user’s intention to continue use. We employed an online survey and obtained a sample of 372 valid responses from TikTok (DouYin) users in China. The partial least squares (PLS) method was used to analyze the data.

The study found that the user experience, in terms of social presence, immersion and credibility perception, can significantly predict users’ intention to continue using short video apps to obtain health information. Furthermore, the user experience was positively associated with the different affordances provided by the short video apps.

The findings of this study have several implications. First, the study contributes to the health information behavior literature by incorporating the aspect of user experience. Moreover, the study extends the application of affordance theory to users’ health information acquisition, and it carries some practical implications on how to leverage the great potential of short video apps to serve public health communication better.