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The purpose of this paper is to analyze the stability behavior of the omnidirectional mobile robot with active dual-wheel caster (ADWC) assemblies and provide a stable trajectory without any tip-over incident. The omnidirectional mobile robot to be developed is for transporting cuboid-shaped objects.

The omnidirectional transport mobile robot is designed using an ADWC assemblies structure, the tip-over occurrence is estimated based on the support forces of an active footprint, the tip-over direction is predicted, the tip-over stability is enhanced to prevent the tip-over occurrence and a fast traveling motion is provided.

The omnidirectional mobile robot tends to tip-over more on the sides with small ranges of tip-over angle. The proposed method for estimating the tip-over occurrence and enhancing the stability using the gyroscopic torque device was feasible as the tip-over prevention system of the omnidirectional mobile robot with ADWC assemblies.

The research addresses the study of the tip-over stability for the omnidirectional mobile robot that possesses an active footprint. It also addresses the prediction of the tip-over occurrence using the derived dynamical model together with force-angle stability measure and the tip-over stability enhancement method using a single-gimbal control moment gyro device.

The purpose of this paper is to develop mathematical tools that are reliable and easily implementable in computer codes, which address the determination of the outriggers reaction of mobile cranes and the monitoring of the actual stability margin available during lift operations.

An algorithm that determines the load transmitted to the ground by a mobile crane with four outriggers has been developed. Static theory of rigid body is adopted for the development of the algorithm and the static indeterminancy, due to the presence of more than three outriggers, is eluded through the adoption of specific hypotheses. An analysis of crane stability is also performed, and a method to monitor the actual stability behavior during lift operations is suggested.

A case study is proposed to test the algorithm and outcomes show a good matching with the actual outriggers reaction measured during a test conduct in situ. Two indices are introduced as a measure of the stability margin.

The method developed accounts only for gravitational forces statically applied. Future works should be addressed to extend the model to the effect of wind and inertial forces.

This paper supplies a reliable tool to assess, in the design phase of a lifting operation, the compliance between bearing capacity of the ground and loads transmitted by outriggers. The method proposed for the analysis of the stability behavior is suitable for the development of an anti-upset device.

This study contributes to efforts to increase safety during lifting operations with mobile cranes. The method proposed is applicable to cranes with any geometry of the outriggers pattern and is extensible to a number of outriggers greater than four. Furthermore, the evaluation of the measure in real time of the stability margin, is not affected by the data entered by the crane’s operator with the consequence that human factor does not affect this measure.

A suspended wheeled mobile robot (SWMR) that consists of one or more manipulators can be exploited in various environmental conditions such as uneven surfaces. The purpose of this paper is to discuss the requirements for stable motion planning of such robotic systems to perform heavy object manipulation tasks.

First, a systematic procedure for dynamics modelling of such complicated systems for planar motion is presented and verified using ADAMS simulation software. Next, based on the new dynamic moment‐height stability (MHS) measure, the stability of such systems will be investigated using the obtained dynamics. To this end, introducing the concept of a virtual frame, the obtained model of SWMR has been employed for investigating the effect of the base suspension characteristics as well as terrain roughness on the stability of the system. Next, the stability evaluation of the system is investigated after toppling down which has been rarely addressed in the literature. In addition, using the aforementioned model, the effect of stiffness is examined after instability.

First, a systematic procedure for dynamics modelling of such complicated systems for planar motion is presented and verified using ADAMS simulation software. Next, based on the new dynamic MHS measure, the stability of such systems will be investigated using the obtained dynamics. To this end, introducing the concept of a virtual frame, the obtained model of SWMR has been employed for investigating the effect of the base suspension characteristics as well as terrain roughness on the stability of the system. Next, the stability evaluation of the system is investigated after toppling down which has been rarely addressed in the literature. In addition, using the aforementioned model, the effect of stiffness is examined after instability.

A general procedure for dynamics modelling of SWMRs is presented. To verify the obtained dynamics model, another model for the considered system has been developed by ADAMS software. Next, using the obtained dynamics, the postural stability of such systems is investigated, based on the new postural MHS measure extended for SWMRs. The obtained simulation results show that by decreasing the stiffness coefficients of suspension subsystem the stability of the system weakens.

The rope-climbing robot that can cling to a rope for locomotion has been a popular piece of equipment for some overhead applications due to its high flexibility. In view of problems left by existing rope-climbing robots, this paper aims to propose a new-style rope-climbing robot named Finger-wheeled mechanism robot (FWMR)-II to improve their performance.

FWMR-II adopts a modular and link-type mechanical structure. With the finger-wheeled mechanism (FWM) module, the robot can achieve smooth and quick locomotion and good capability of obstacle-crossing on the rope and with the link module based on a spatial parallel mechanism, the robot adaptability for rope environments is improved further. The kinematic models that can present configurations of the FWM module and link module of the robot are established and for typical states of the obstacle-crossing process, the geometric definitions and constraints that can present the robot position relative to the rope are established. The simulation is performed with the optimization calculating method to obtain the robot adaptability for rope environments and the experiment is also conducted with the developed prototype to verify the robot performance.

From the simulation results, the adaptability for rope environments of FWMR-II are obtained and the advantage of FWMR-II compared with FWMR-I is also proved. The experiment results give a further verification for the robot design and analysis work.

The robot proposed in this study can be used for inspection of power transmission lines, inspection and delivery in mine and some other overhead applications.

An ingenious modular link-type robot is proposed to improve existing rope-climbing robots and the method established in this study is worthy of reference for obstacle-crossing analysis of other rope-climbing robots.

The purpose of this paper is to develop an electronic solution to effectively lock swivelling wheel steering positions to driver‐control. Simple and affordable systems are described to assist forklift users in steering their walkie type forklifts or pallet jacks across sloping ground.

A rolling road was created as an assessment tool and trials with both the test bed and in real situations were conducted to evaluate the new systems. The small swivel detector that was created could be successfully attached to swivelling wheel swivel bearings.

The new system was successful, robust and was not affected by changeable parameters. The simple systems assisted hand truck operators in steering their forklifts across sloping ground without veering off course. The systems overcame the problems associated with forklifts that steer using two swivelling wheels and meant that less work was required from hand truck operators as their forklifts tended to travel in the desired direction

Experiments demonstrated that calibrating forklift controllers for straight‐line balance and optimizing motor‐compensation did not solve this problem. Instead, swivelling wheel angle was selected to provide feedback. At the point when veer is first detected, a forklift has already begun to alter course and the job of the correction system is to minimize this drift from the desired course.

The forklifts and pallet jacks often steer by having swivelling wheels but problems with this configuration occur when a forklift is driven along sloping ground because they can swivel in the direction of the slope. Gravity then causes the forklift or pallet jack to start an unwanted turn or “veer” and the vehicle goes in an unintended direction. This situation is exacerbated for vehicles with switch controls, as switches cannot provide fine control to trim and compensate.

Each year in the United States, over 100 employees are killed and 36,000 are seriously injured in accidents involving forklift trucks and pallet carriers. This is the second leading cause of occupational fatalities in “industrial” type workplaces. The research aims to make the use of this type of equipment safer and the systems can be attached to many standard forklifts and pallet jacks.

The purpose of this paper is to improve control performance and safety of a real two-wheeled inverted pendulum (TWIP) robot by dealing with model uncertainty and motion restriction simultaneously, which can be extended to other TWIP robotic systems.

The inequality of lumped model uncertainty boundary is derived from original TWIP dynamics. Several motion restriction conditions are derived considering zero dynamics, centripedal force, ground friction condition, posture stability, control torque limitation and so on. Sliding-mode control (SMC) and model predictive control (MPC) are separately adopted to design controllers for longitudinal and rotational motion, while taking model uncertainty into account. The reference value of the moving velocity and acceleration, delivered to the designed controller, should be restricted in a specified range, limited by motion restrictions, to keep safe.

The cancelation of model uncertainty commonly existing in real system can improve control performance. The motion commands play an important role in maintaining safety and reliability of TWIP, which can be ensured by the proposed motion restriction to avoid potential movement failure, such as slipping, lateral tipping over because of turning and large fluctuation of body.

An inequation of lumped model uncertainty boundary incorporating comprehensive errors and uncertainties of system is derived and elaborately calculated to determine the switching coefficients of SMC. The motion restrictions for TWIP robot moving in 3D are derived and used to impose constraints on reference trajectory to avoid possible instability or failure of movement.

The key ideas of cybernetics have remained unknown or misunderstood by contemporary technological societies. The purpose of this paper is to consider how best to assist individuals outside the cybernetics and systems communities in learning key concepts of cybernetics.

The main approach used to make this case is consideration of how individuals can come to understand circular systems and circular causality. The paper makes a case that if we want to assist interested others in learning cybernetics, we can best do so either by identifying where interested others already have experiences that they can reinterpret in terms of causality through investigation, analysis, and conversation or by designing experiences such as interactive models and simulations that become the basis of each user’s inventing an understanding of circular causality, and then, through analysis and conversation, refining that understanding. It provides examples, in particular, the example of how learning to sail a small boat involves the sailor in creating an intuitive (and possibly formal) understanding of wind, water, and boat as elements of a circular system. The paper considers the ethics of assisting others in learning cybernetic concepts such as circular causality.

The paper provides an approach to understanding cybernetic concepts that can be used with students and adults of all ages.

This paper ties together theoretical and practical considerations from a constructivist viewpoint.

Through the development of the example of the Greek helmsman, the kybernetes, the paper provides a point of departure for those in the cybernetics and systems communities involved in designing teacher-based or web-based materials for cybernetics.

The paper has value as a guide to practice.

The purpose of this paper is to provide a sector-based analysis of the drivers for social entrepreneurship in the agricultural sector.

The paper uses qualitative data from two studies in the Danish region of Northern Jutland. The data include responses from 38 farmers who offered or had considered offering social services. The analytical framework is taken from a review of the limited literature on Green Care and Social Farming and social entrepreneurship theory.

Strong and consistent tools for the categorisation of farmers’ social entrepreneurship have been developed. However, these tools have merely been used descriptively rather than to create proactive agriculture policies to facilitate social entrepreneurship. In Region Northern Jutland social entrepreneurship in farming is driven by a combination of tradition, close relationships and coincidence. It is ad hoc, with each initiative starting from scratch because no knowledge or experience has been gathered or distributed.

The agricultural sector-based approach to social entrepreneurship will not be discussed against other approaches to social entrepreneurship. This would be a suggestion for another more conceptual kind of article in the future.

A study of social entrepreneurship among farmers has not yet been coupled with a sector-based analytical framework. This paper contributes to the literature of social entrepreneurship by supplementing with an agricultural sector-based approach.

The purpose of this paper is to propose that librarians consider new ways of working in order to manage new types of electronic sources.

This paper is based on a literature survey, readings outside the literature, and observations in the field.

Librarians need to think out of the box, change how they structure their organizations and work, and cede more control to users.

This is an opinion piece urging librarians to think differently.

If librarians could think out of the box, give up their traditional organizational lines, and cede more control to users, managing new forms of electronic resources would be easier.

Changing ways of thinking is a long, difficult process.

This paper was originally presented at the IFLA conference in Milan in August 2009.

The aim of the current study is proposing a novel framework to attain the optimum value of a flexible arm manipulator parameters for payload launching missions.

The proposed scheme is based on optimal control approach and combines direct and indirect search methods while considering the actuator capacity.

Three nonlinear parameter-optimization problems will be solved to illustrate how the proposed algorithm can be exploited. Employing variational based nonlinear optimal control within the suggested framework, the answer of these problems is highly intertwined to the solution of a set of differential equations with split boundary values. To solve the obtained boundary value problem (BVP), the related solver of MATLAB® software, bvp6c, will be employed. The achieved simulation results support the worth of the developed procedure.

For the first time, the optimal parameters of a flexible link robot for object launching are found in the current research. In addition, the actuator saturation limits are considered which enhances the applicability of the suggested method in the real world applications.