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The purpose of this paper is to develop a portable all‐position welding robot for the welding of intersected pipes.

A complete procedure is adopted to conduct the design. The task and motion of the robot are analyzed and a mathematical description of the pose and position of the welding tool is given. Based on that, three representative types of robot are chosen in the type synthesis of mechanism. Two new indices proposed to evaluate required properties of the robot, along with the traditional dexterity index, are chosen to be the criteria in the dimension synthesis of mechanism. Through the optimization by genetic algorithm, the best robot in type and dimension is determined after comparison on their performances. Finally, the prototype is developed.

The paper finds a new robot for welding intersected pipes.

A new robot is introduced for the welding of intersected pipes. A complete design procedure is adopted to conduct the design. Two new indices are constructed for evaluating the required properties of this robot.

The purpose of this paper is to apply a factorization‐based control system design procedure to design of auto‐pilot systems.

The design approach is based on a previously developed factorization‐based control system design procedure. The design approach requires a stable coprime factorization of the plant, a set of stable coprime factors that are solutions to the Bezout identity, the linear model of a desired response, and the desired frequency range of interest. When all this information is provided, the developed automated software outputs a candidate auto‐pilot whose performance should be verified.

For a specific class of aerospace vehicles, it is found that the described factorization‐based auto‐pilot design procedure may replace the presently complicated auto‐pilot design procedures. The final design is simpler than other techniques that are based on classical, robust, adaptive, QFT, gain scheduling, or interpolation techniques, and the total required man hours for the design loop is less than the mentioned alternative approaches.

There are two basic limitations – time variations of plant parameters must not be very large as is the case with the agile aerospace vehicles, and specification of the desired closed‐loop system behavior is not systematic.

The major outcome of this research is that complicated autopilots of a class of aerospace vehicles may be replaced by simpler systems with competitive performance.

This is the first paper in the area of autopilot design that is based on the application of a simple factorization‐based design procedure.

To apply and simulate under different conditions, the combined model reference adaptive control (CMRAC) technique to control the pitch angle in a subsonic plane. Comparisons with the classical PID controller and the adaptive direct MRAC are also performed.

The methodology used in this work is the CMRAC. This is a relatively new adaptive control technique which combines the information coming from the identification procedure as well as that from the direct control scheme, and use it in the adaptive laws. The identification parameters and the controller parameters are simultaneously adjusted using the identification error, the control error and the so‐called close‐loop identification error. This combination has shown to improve the transient behavior of the adaptive systems.

This control scheme has been tested by simulation on a model of a CESSNA 182 plane, to control the pitch angle (longitudinal movement). The results have been compared with other control approaches such as the classical PID and the adaptive direct MRAC. Although the PID control satisfies all the control specifications as much as the CMRAC, it is not able to adapt when changes in the operating conditions occur, as in the case of the CMRAC. The direct MRAC does no perform well in this study.

The implementation at practical level remains to be studied and analyzed, to verify the theoretical and simulation results presented here.

The main advantage of the proposed method is that it behaves well even under different operating conditions, which is one of the most important characteristics for an implementation at practical level.

It is the first time in the control literature that the CMRAC is applied to control the pitch angle of a plane in a longitudinal movement. The results are quite promising remaining the practical implementation to verify the performance of the proposed scheme under real conditions.

In this paper we propose a new method for the creation of subject bibliographies. Our method consists of two phases: first, the raw bibliographical material is downloaded from an online bibliographical database (e.g. DIALOG), and then this material is processed using knowledge‐based means. We apply a meta‐programming approach in which the raw bibliographic material is viewed as a logic program upon which we develop a second‐order logic program. The second‐order program creates the subject bibliography by operating a rule base and the first‐order logic program. The entire system, named REX, was written in PROLOG and used to create automatically a subject bibliography on Applications of Logic Programming in Decision and Control.

This paper aims to address the spacecraft attitude control problem using hybrid actuators in the presence of actuator saturation, uncertainties and faults, inertia uncertainties and external disturbances.

A hybrid actuator configuration is used where thrusters are engaged for rapid attitude maneuvers, while reaction wheels (RWs) are used for fine pointing.

The key advantages are two-fold: a finite-time high-level controller is designed to produce the three-axis virtual control torques; an online robust control allocation (RobCA) scheme is proposed to redistribute virtual control signals to the actuators with taking into account the actuator saturation, uncertainties and faults; and the RobCA scheme allows a smooth switch between thrusters and RWs, which handles the inaccuracy problem of thrusters and saturation problem of RWs.

An online RobCA algorithm is designed that maps the total control demands onto individual actuator settings and allows a smooth switch between thrusters and RWs. Simulation results show the effectiveness of the proposed control strategy.

This work may be used on modern space missions, which impose higher requirements on smooth switching of spacecraft thrusters and RWs.

Development and application of a new systematic approach for design of a control system in order to control the mixture ratio of liquid propellant engines.

The design approach is based on a full nonlinear dynamic model of the engine, and the controller design method is based on describing function models of the engine coupled with the factorization theory. The presented systematic design procedure is comprised of five primary steps. The developed software for the design approach is in the MATLAB environment.

It is found that the presented design approach may successfully be used to control the mixture ratio of a class of liquid propellant engines whose control loops are decoupled. The performance and robustness of the designed controller is found to be satisfactory.

At present, the research is limited to liquid propellant engines whose control loops are decoupled.

The major outcome of this research is that complicated hydromechanical control valves that are used to control the mixture ratio may be replaced by simple microprocessor based servomechanisms that drive simple valves. This will allow for the engine to accept various set point values for mixture ratio as is required in multi‐regime engines.

This is the first paper in the area of mixture ratio control of a liquid propellant engine that is based on the application of describing function approach coupled with the factorization theory.

New Communications Systems will Affect Computer Jobs? One of the constant worries about the new high‐tech developments that are announced with such frequency is their effect on the employment market. Throughout the ages each new discovery has affected the working patterns of society but more than ever before the rapid growth in new technology has quickly altered not only the way in which we work but the number of people who can work. It does not require a social scientist or a cybernetician working in this field to inform society of the effects that will accrue from the apparently never ending technological advances that are being announced, and subsequently implemented. Each one produces a scare of enormous proportions. In the 1950s the computer was to put most people out of work, the microcomputer “revolution” was later expected to make sure that those who kept their jobs would soon be redundant. Fortunately, these predictions were not true and although the world's workforces have changed in so many instances to accommodate the new technology the age of total leisure or of mass unemployment has yet to arrive.

The current study aims to empirically examine the impact of formal salesforce control systems on salespeople and customer behavior.

Data are collected from 704 salespeople and their respective visiting customers (704) in Ghana. The suggested hypotheses are tested through the structural equation (SEM) modeling technique.

The study results show that all three formal control mechanisms have positive and significant effects on customer-directed problem-solving and adaptive selling behaviors. Similarly, the study finds that salespeople's customer-directed problem-solving behavior increases, respectively, customer-directed opportunism and relationship continuity. Adaptive selling behavior also has significant positive effects on both customer-directed opportunism and relationship continuity, respectively.

The study offers practical and theoretical insights into understanding salesforce control dynamics, customer-directed opportunism, adaptive selling behavior, customer-directed problem-solving behavior and continuity of relationships. The results also have significant consequences for sales organizations as they can help sales managers decide on the best form of salesforce control systems to deploy.

The current research demonstrates how control mechanisms can influence both adaptive selling and customer-directed problem-solving behaviors and how these could generate both customer-directed opportunism and relationship continuity.

This bibliometric mapping study aimed to provide comprehensive insights into the global research landscape of cybernetics. Utilizing the biblioshiny function in R Studio, we conducted an analysis spanning 1958 to 2023, sourcing data from Scopus. This research focuses on key terms such as cybernetics, cybernetics systems, complex adaptive systems, viable system models (VSM), agent-based modeling, feedback loops and complexity systems.

The analysis leveraged R Studio’s biblioshiny function to perform bibliometric mapping. Keyword searches were conducted within titles, abstracts and keywords, targeting terms central to cybernetics. The timespan, 1958–2023, provides a comprehensive overview of the evolution of cybernetics-related literature. The data were extracted from Scopus to ensure a robust and widely recognized source.

The results revealed a rich and interconnected global research network in cybernetics. The word cloud analysis highlights prominent terms such as “agent-based modeling,” “complex adaptive systems,” “feedback loop,” “viable system model” and “cybernetics.” Notably, the journal Kybernetes has emerged as a focal point, with significant citations, solidifying its position as a key source within the cybernetics research domain. The bibliometric map provides visual clarity regarding the relationships between various concepts and their evolution over time.

This study contributes original insights by employing advanced bibliometric techniques in R Studio to map the cybernetics research landscape. The comprehensive analysis sheds light on the evolution of key concepts and the global collaborative networks shaping cybernetics research. The identification of influential sources, such as Kybernetes, adds value to researchers seeking to navigate and contribute to the dynamic field of cybernetics. Furthermore, this study highlights that cybernetics not only provides a useful framework for understanding and managing major economic shocks but also offers perspectives for understanding phenomena in various fields such as economics, medicine, environmental sciences and climate change.

Digital solutions (DS) that build on recurring revenue models (RRMs) offer new opportunities to continuously create and capture superior value. However, many firms fail to engage their sales force in digital solution selling (DS selling), leading to agency problems that receive little attention in literature. This study aims to examine the drivers of agency problems that surface in the transition toward DS selling and the sales control systems that resolve these problems.

The authors conducted a qualitative, inductive study. Data were collected from interviews with 72 marketing and sales managers representing 53 industrial firms transitioning toward DS selling.

DS selling is subject to adverse selection and moral hazard caused by motivation-related, opportunity-related and ability-related drivers. Input, capability, activity and outcome controls – detailed in this study – can resolve these agency problems.

The limitations of this study’s methodology and scope suggest several directions for future research. Methodology-wise, the authors mainly relied on cross-sectional interview data from informants in Central and Northern Europe. Scope-wise, more research is needed on the capabilities, processes and steering instruments supporting DS sales. Finally, only now do the authors begin to understand which compensation plans motivate DS selling.

The controls identified in this study help managers to steer their sales force in DS sales.

To the best of the authors’ knowledge, this study is the first to investigate DS sales control systems. Thereby, the authors enhance prior understandings of solution selling, agency problems and sales control systems.