confined spaces
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The paper presents the structuring of physical effort put in by rescuers during training, taking into account the activity specific psychosocial factors, structuring that aimed at streamlining the training process of intervention and rescue personnel in toxic / explosive / flammable environments. Training routes with various degrees of difficulty, allowing the simulation of intervention activities in horizontally and vertically confined spaces, low visibility, high temperature and humidity environments were analysed, for each the specific labour consumption being calculated. A dysfunctional phenomenon caused by the intervention and rescue activity is fatigue, perceived as a body reaction to readjust and restore its functions following intense or repeated body requests for energy consumption. Not only physical fatigue (which can be controlled through exercises) is specific for rescue and intervention activity but also mental fatigue. In addition to physical and technical training, psychosocial training of people who carry out intervention and rescue activities was followed in the training programs.

This paper considers the possibility of using a stepping robot - hexapod for research, monitoring the condition of technical dry channels, enclosed spaces and more. Compared to existing designs used today, the hexapod has a list of advantages that make it a more versatile tool, namely: autonomy, due to the power supply installed at work, design features that ensure its increased patency on uneven surfaces. Instead, this type of work requires the development of complex algorithms for movement than in the case of wheeled or tracked machines, ie. hexapod is a platform that moves the limbs, which in turn move with the help of servos. Therefore, the movement of the platform is provided by the control of each servo. In addition, environmental information is additionally processed from rangefinders, limb con-tact sensors with the surface, cameras, accelerometers, etc. Particular attention is paid to robot rotation algorithms, as the proposed scope imposes restrictions on the ability to maneuver freely in space. An algorithm for rotating robots in confined spaces based on limb state matrices has been developed, which greatly simplifies the practical implementation and allows to easily change the type of stroke during the hexapod operation. It is also proposed to introduce a buffer state matrix, which allows you to remember the last position of the limbs of the robot in case of its failure, after the elimination of which, it is possible to continue moving from any last state. Or return to the starting position and change the route. The versatility of the algorithm allows its use not only in the development of the software part of the hesapod, but also for other types of walking robots. Since the developed algorithm allows you to easily modify the types of moves at each iteration of the step. In the future, it is planned to test this algorithm on a model of a hexapod and supplement it with the necessary components for vertical movement, which is very important for passability in this area of application.

Search and rescue operations can range from small, confined spaces, such as collapsed buildings, to large area searches during missing person operations. K9 units are tasked with intervening in such emergencies and assist in the optimal way to ensure a successful outcome for the mission. They are required to operate in unknown situations were the lives of the K9 handler and the canine companion are threatened as they operate with limited situational awareness. Within the context of the INGENIOUS project, we developed a K9 vest for the canine companion of the unit, aiming to increase the unit’s safety while operating in the field, assist the K9 handler in better monitoring the location and the environment of the K9 and increase the information provided to the Command and Control Center during the operation.

For poly(2,6-dimethyl-1,4-phenylene)oxide (PPO) films exhibiting nanoporous-crystalline (NC) phases, c^ orientation (i.e., crystalline polymer chain axes being preferentially perpendicular to the film plane) is obtained by crystallization of amorphous films, as induced by sorption of suitable low-molecular-mass guest molecules. The occurrence of c^ orientation is relevant for applications of NC PPO films because it markedly increases film transparency as well as guest diffusivity. Surprisingly, we show that the known crystallization procedures lead to c^ oriented thick (50–300 μm) films and to unoriented thin (£20 μm) films. This absence of crystalline phase orientation for thin films is rationalized by fast guest sorption kinetics, which avoid co-crystallization in confined spaces and hence inhibit formation of flat-on lamellae. For thick films exhibiting c^ orientation, sigmoid kinetics of guest sorption and of thickening of PPO films are observed, with inflection points associated with guest-induced film plasticization. Corresponding crystallization kinetics are linear with time and show that co-crystal growth is poorly affected by film plasticization. An additional relevant result of this study is the linear relationship between WAXD crystallinity index and DSC melting enthalpy, which allows evaluation of melting enthalpy of the NC α form of PPO (DHmo = 42 ± 2 J/g).

The traditional deep-water manipulators have several problems to work in confined spaces, such as large volume, complex structure, and inability. To solve these problems, a novel cable-driven snake-like manipulator robot for deep-water is proposed. In this study, the structure design of the cable-driven snake-like manipulator robot is first introduced. Then, we establish the kinematics model of the proposed cable-driven snake-like manipulator robot, which includes three parts: motor-cable kinematics, cable-joint kinematics, and joint-end kinematics. Especially, a tip-following algorithm (Supplemental Material) is presented to fit the confined and complicated underwater scenarios. Furthermore, a kinematics control strategy based on fuzzy PID controller is presented to reduce the tracking error caused by transmission mechanism, and the simulation of the cable-driven snake-like manipulator is carried out based on the MATLAB. The results demonstrate that the tracking error is less than 0.04 mm, which shows the proposed control strategy is effective.

The objective of this paper is to acknowledge that major tank coating refurbishment projects to FPSO’s and FSU’s are likely to be required during the life of these assets. It highlights the key challenges of achieving these major coating projects in an offshore environment, whilst the assets remain operational and in-production. As these floating assets age the original coatings applied to protect the internal (and external) hull, deteriorate. In an industry with a reluctance for extensive dry-dockings, there is an expectation that any coating refurbishment campaigns can be achieved safely and efficiently whilst the assets remain on-station and in-production, in preference to costly steel renewal’s which may be required at a future date if coatings are not maintained in good condition. With often complex, congested and hazardous topsides processing equipment and pipework directly above the hull tanks, there’s a need for systems, procedures, and specialist equipment to ensure the safety of the personnel entering confined spaces for extended periods. There’s also a need to plan and engineer the works appropriately, using best practice and emergent technologies to improve safety, reduce bedding impacts and to ensure the success of the coating campaign. This paper explores the challenges of major coating projects by discussing the importance of planning and preparation, the need to create a safe working environment within the confined space worksites, the role surface preparation plays in the success of coating projects, and finally the application of coatings and the challenges this operation can present. The key considerations are summarised in 10 specific conclusions as guidance to promote successful project outcomes.

AbstractBacteria often form surface-bound communities, embedded in a self-produced extracellular matrix, called biofilms. Quantitative studies of their growth have typically focused on unconfined expansion above solid or semi-solid surfaces, leading to exponential radial growth. This geometry does not accurately reflect the natural or biomedical contexts in which biofilms grow in confined spaces. Here we consider one of the simplest confined geometries: a biofilm growing laterally in the space between a solid surface and an overlying elastic sheet. A poroelastic framework is utilised to derive the radial growth rate of the biofilm; it reveals an additional self-similar expansion regime, governed by the stiffness of the matrix, leading to a finite maximum radius, consistent with our experimental observations of growing Bacillus subtilis biofilms confined by PDMS.