Force Capability Research Articles

An Adaptive Algorithm and Additively Manufactured Punch Used to Form Aluminum Sheet Metal Parts.

Self-adaptive mechanisms are gaining momentum in industrial processes. It is understandable that as the complexity increases, the human work must be augmented. Considering this, the authors have developed one such solution for the punch-forming process, using additive manufacturing, i.e., a 3D-printed punch, to draw into shape 6061-T6 aluminum sheets. This paper aims to highlight the topological study used to optimize the punch form shape, the methodology of the 3D printing process, and the material used. For the adaptive algorithm, a complex Python-to-C++ bridge was created. It was necessary as the script has computer vision (used for calculating stroke and speed), punch force, and hydraulic pressure measurement capabilities. The algorithm uses the input data to control its subsequent actions. Two approaches are used in this experimental paper, a pre-programmed direction and an adaptive one, for comparison purposes. The results, namely the drawing radius and flange angle, were statistically analyzed using the ANOVA methodology for significance. The results indicate significant improvements when using the adaptive algorithm.

Versatile end effector for laparoscopic robotic scrub nurse

PurposeIntegrating robotic scrub nurses in the operating room has the potential to help overcome staff shortages and limited use of available operating capacities in hospitals. Existing approaches of robotic scrub nurses are mainly focused on open surgical procedures, neglecting laparoscopic procedures. Laparoscopic interventions offer great potential for the context-sensitive integration of robotic systems due to possible standardization. However, the first step is to ensure the safe manipulation of laparoscopic instruments.MethodsA robotic platform with a universal gripper system was designed to pick up and place laparoscopic as well as da Vinci^{circledR } instruments in an efficient workflow. The robustness of the gripper system was studied using a test protocol, which included a force absorption test to determine the operational safety limits of the design and a grip test to determine the system performance.ResultsThe test protocol shows results regarding force and torque absorption capabilities of the end effector, which are essential when transferring an instrument to the surgeon to enable a robust handover. The grip tests show that the laparoscopic instruments can be safely picked up, manipulated and returned independent of unexpected positional deviations. The gripper system also enables the manipulation of da Vinci^{circledR } instruments, opening the door for robot–robot interaction.ConclusionOur evaluation tests have shown that our robotic scrub nurse with the universal gripper system can safely and robustly manipulate laparoscopic and da Vinci^{circledR } instruments. The system design will continue with the integration of context-sensitive capabilities.

Design and Characterization of 2.5D Nature-Inspired Infill Structures under Out-Plane Quasi-Static Loading Condition

The 2.5D (2.5-dimensional) structures are acquired to enhance safety and lightweight designs with better energy absorption in the aerospace and automobile sectors. Additive manufacturing (AM), which is practical to build suitable components in industrial and transportation applications, may produce these structures more efficiently. The current study aims to improve the 2.5D infilled structures mean crush force (MCF) and energy absorption capabilities. Under compression loading, the proposed novel nature-inspired 2.5D infilled structure is compared to six existing 2.5D geometries that are inspired by nature. These structures are made of cylindrical shells that are filled with various infill configurations and maintained at a consistent volume. Photopolymer resin is used as the material for the structures, which are created using a digital light processing (DLP) method under AM technology. The characterization of the constructed models was done under compressive out-plane quasi-static stress conditions. ANSYS numerical simulations have been carried out to confirm the dependability of experimental data. The impact of supporting ribs and infill designs on crushing behaviour is thoroughly discussed. Mean crush force (MCF) and specific energy absorption (SEA) under quasi-static compression loading are provided to the proposed unique nature-inspired 2.5D infilled structure to significantly boost crushing qualities, axial collapse, and energy absorption behaviours.

Development of a flexible high-friction pressure sensor with structural colors for soft gripper fingers

For energy-efficient and lightweight sensor applications, structural colors were utilized to sense the pressure applied to the surface. However, conventional structural color sensors have been usually fabricated with nanoscale features focusing on high pressure sensitivity with small load limits. In this study, a flexible surface with high frictional force and wide pressure-sensing capability was fabricated by ultra-precision machining for soft gripper applications. Friction and grip detection are very important for gripping performance and sensors for soft grippers are required to cope with loads of over 1 kg. Here, microscale three-dimensional trapezoidal patterns were fabricated and transferred to a polymer to increase the contact area for higher friction and improve structural color expression. The effects of pattern geometry on structural color changes due to the varying loads were analyzed using the hue, saturation, and brightness (HSB) model. The hues of the patterned surfaces decreased with loads. Clear color changes were apparent as the pattern width and depth varied; patterns with blue colors (hue of ~240) at no-load status sensed pressure most effectively. Based on the experimental results, a sensor was designed to have a clear color change in terms of pressure and then was applied to soft gripper fingers. Significant color changes were evident as the pressure changed during gripping even under large loads of up to 1200 g; the high friction (compared to that of a plain surface) also improved gripping performances. The sensor provides intuitive information detectable by the naked eye, and there is no need for any power source, wire, or data acquisition system. This research can contribute to the development of multi-functional, lightweight energy-efficient systems.

Comparative Study of Linear Variable Flux Reluctance Machine with Linear Wound Field Flux Reversal Machine

As members of doubly salient magnetless linear machines, linear variable flux reluctance (LVFR) and wound field flux reversal (LWFFR) machines inherit the merits of conventional magnetless linear machines such as low cost, high flux adjustment capability and high reliability. Furthermore, like linear switched reluctance machine, they have a very simple and compact long secondary, which are very attractive for long stroke applications. However, low force capability is their major defect. To solve this issue, new LVFR and LWFFR machine topologies were proposed in recent work, while lacking studies on their force improvement mechanism and further force evaluation. In this paper, LVFR and LWFFR machines with improved force performance are comparatively studied with the emphasis on their force capabilities. The operation principle of the two machines is analyzed based on magnetic field harmonics produced by flux modulation. Contributions of air-gap flux density harmonic components to no-load back electromagnetic forces of the two machines are analyzed and the average force equation is derived. Moreover, force capabilities of the both machines are investigated by means of the time-stepping finite-element analysis to verify the theoretical analysis.

Optimization and Experimentation of Fault-Tolerant Field Excited Linear Flux Switching Machine With Concentrated and Toroidal Windings for Rail Transportation System

In this article two double-sided Field Excited Linear Flux Switching Machines (FELFSM) are analyzed. Both machines share the same robust and compact stator structure with a modular mover design having different winding configurations namely concentrated and toroidal. The proposed machines have a low-cost owing to the lack of rare earth materials, a high fault-tolerant capability due to the modular construction of the mover, and flux controllability due to field current variation. The initial designs are optimized through a genetic algorithm using JMAG software ver. 20.1. to maximize the thrust force and minimize thrust force ripples ratio. After optimization, the average thrust force in Machine I and Machine II is increased by 31.96% and 32.31%, respectively. Additionally, a mathematical model is developed to compute electromagnetic thrust force and fault-tolerant capability. The electromagnetic performance of both machines are compared through 2D FEA. Both analytical and FEA-based designs are verified through experimental validation on the developed prototype. Finally, a coupled electromagnetic-thermal study is carried out, with the temperature of the prototype being visualized experimentally using a Fluke VT04 IR thermometer.

Development of an ultra-low-cost planar biaxial tester for soft tissue characterization

Nowadays, the research in the arena of biomedical engineering or specifically soft tissue characterization is rapidly increasing. Due to the complex properties of soft tissues such as, anisotropy and viscoelasticity, it is difficult to predict the deformation behaviour. Hence, soft tissue characterization is essential to analyze these metrics. Soft tissue characterization, specifically, can be done by implementing a planar biaxial tester. Currently, available biaxial testers are mostly developed with respect to other mechanical components such as metals, and not for the soft tissues. Also, these devices are very costly, which makes it difficult for the low and middle income countries to perform this characterization. To solve this problem, in this work, an extremely low-cost biaxial tester was designed and developed. The design of the biaxial tester was simple and modular to allow device modifications according to the applications. The device has a force capability of less than 0.4 kN and a variable speed of 18 mm min−1 to 300 mm min−1. The biaxial tester was validated using a standard test material with mechanical testing machine and was further tested on several wound geometries including circular, square, diamond shaped, L-Plasty, and elliptical. The developed fully automated device exhibited high accuracy with real-time monitoring. Furthermore, test results on the wounds showed the device’s capability to differentiate amongst the considered wound geometries. This device can be helpful to medical students and doctors in understanding the mechanical behaviour of soft tissues during injury induced damage, disease, wounds healing and also for plethora of applications such as expansion testing of skin grafts.

Motorized Robotic Closed Cervical Traction: Biomechanical Proof of Concept.

Biomechanical study. To demonstrate that robotic cervical traction can apply closed cervical traction as effectively as manual weight-and-pulley traction in extension spring and cadaveric models. Closed cervical traction is used to reduce subaxial cervical spine dislocation injuries and to distract the intervertebral space during cervical spine surgery. Weight-and-pulley cervical traction relies on cumbersome and imprecise technology without any safeguard to prevent over-traction or weights being pulled/released inadvertently. A prototype robotic traction device was designed and manufactured by the authors with real-time tensile force measurement, ±1-lbs (5 N) force application accuracy, locking/non-backdriveable linear actuators with actuator position sensing, 200-lbs (900 N) maximum force capability, up to 20° of flexion/extension manipulation, <25-lbs (111 N) device weight, and compatibility with Gardner-Wells tongs or Mayfield head clamp. The device was tested using an extension spring model and an intact fresh cadaver specimen to assess applied and desired force over time and radiographic changes in the cervical spine as traction force increased. The cadaver was tested in manual traction initially and then robotic traction in 10-lbs (50 N) increments up to 80-lbs (355 N) to compare methods. The prototype device met or exceeded all requirements. In extension spring testing, the device reached the prescribed forces of both 25-lbs (111 N) and 80-lbs (355 N) accurately and maintained the desired weight. In cadaveric testing, radiographic outcomes were equivalent between the prototype and manual weight-and-pulley traction at 80-lbs (355 N; disk space measurements within ±10% for all levels), and the device reached the desired weight within±1-lbs (5 N) of accuracy at each weight interval. This preliminary work demonstrates that motorized robotic cervical traction can safely and effectively apply controlled traction forces.

Estimates of absolute crown strength and bite force in the lower postcanine dentition of Gigantopithecus blacki

Gigantopithecus blacki is hypothesized to have been capable of processing mechanically challenging foods, which likely required this species to have high dental resistance to fracture and/or large bite force. To test this hypothesis, we used two recently developed approaches to estimate absolute crown strength and bite force of the lower postcanine dentition. Sixteen Gigantopithecus mandibular permanent cheek teeth were scanned by micro-computed tomography. From virtual mesial cross-sections, we measured average enamel thickness and bi-cervical diameter to estimate absolute crown strength, and cuspal enamel thickness and dentine horn angle to estimate bite force. We compared G. blacki with a sample of extant great apes (Pan, Pongo, and Gorilla) and australopiths (Australopithecus anamensis, Australopithecus afarensis, Australopithecus africanus, Paranthropus robustus, and Paranthropus boisei). We also evaluated statistical differences in absolute crown strength and bite force between the premolars and molars for G. blacki. Results reveal that molar crown strength is absolutely greater, and molar bite force absolutely higher, in G. blacki than all other taxa except P. boisei, suggesting that G. blacki molars have exceptionally high resistance to fracture and the ability to generate exceptionally high bite force. In addition, G. blacki premolars have comparable absolute crown strength and larger bite force capabilities compared with its molars, implying possible functional specializations in premolars. The dental specialization of G. blacki could thus represent an adaptation to further facilitate the processing of mechanically challenging foods. While it is currently not possible to determine which types of foods were actually consumed by G. blacki through this study, direct evidence (e.g. dental chipping and microwear) left by the foods eaten by G. blacki could potentially lead to greater insights into its dietary ecology.

Hybrid artificial muscle: enhanced actuation and load-bearing performance via an origami metamaterial endoskeleton.

Owing to their compliance, soft robots demonstrate enhanced compatibility with humans and the environment compared with traditional rigid robots. However, ensuring the working effectiveness of artificial muscles that actuate soft robots in confined spaces or under loaded conditions remains a challenge. Drawing inspiration from avian pneumatic bones, we propose the incorporation of a lightweight endoskeleton into artificial muscles to augment the mechanical integrity and tackle load-bearing environmental difficulties. We present a soft origami hybrid artificial muscle that features a hollow origami metamaterial interior with a rolled dielectric elastomer exterior. The programmable nonlinear origami metamaterial endoskeleton significantly improves the blocked force and load-bearing capability of the dielectric elastomer artificial muscle and an increased actuation strain. The origami hybrid artificial muscle demonstrates a maximum strain of 8.5% and a maximum actuating stress of 12.2 mN mm-2 at 30 V μm-1 while preserving its actuating ability, even under a 450 mN load, which is equivalent to 155 times its own weight. We further investigate the dynamic responses and demonstrate the potential use of the hybrid artificial muscle in flapping-wing actuation applications.

The Future Combat Pilot - Asleep at the Wheel?

Technology is a key driver for Air Force capability. There is always debate on the future technology that can advance our future combat aircraft such as artificial intelligence (AI), quantum computing and stealth technology. But what about the human in this human-machine team? There appears to be little debate about the humans in this team.

Koncept totalne odbrane u strategiji odvraćanja Republike Srbije

The subject of this article refers to the examination of the convenience of the concept of total defense as a basis for designing a defense system in the function of strategic deterrence of the Republic of Serbia. The existing defense system was supposed to be based on the concept of total defense, which has not been defined, verified and generally accepted since the Republic of Serbia was founded. In accordance with the above, the question arises: whether the existing way of organizing and functioning of the defense system corresponds to the requirements of strategic deterrence. The starting point in this paper is the position that the defense system, without a previously defined and generally accepted concept of total defense, may not be fully efficient and effective in creating a credible and persuasive threat in the function of strategic deterrence. The results of the research indicate that in order to develop the necessary defenece forces capabilities and their use for strategic deterrence, it is necessary to first develop the concept of total defense. Through the development process, it is possible to achieve full agreement of all forces on their tasks, methods of engagement and associated risks. Also, with the concept of total defense, it is possible to determine measures and recommendations on changes in the existing defense system that should increase the effectiveness and efficiency of strategic deterrence. The theoretical-methodological approach used a theoretical analysis and comparison of total defense concepts in different historical and geopolitical conditions, as well as a method concept development that can meet the requirements of strategic deterrence in the conditions of a modern multidimensional strategic environment.

PECULIARITIES OF THE STATE SYSTEM OF STRATEGIC PLANNING OF NATIONAL SECURITY UNDER THE CONDITIONS OF INFORMATIZATION OF SOCIETY

The inefficiency of the national security system is one of the biggest threats to Ukraine's national security. The strategic planning in the field of security and defense has been developed to identify the means, including the future structure of forces, which would allow the institutions of the defense and security sector to deal with potential future threats effectively. The purpose of this study is development of theoretical and practical measures to increase the effectiveness of strategic management of national security processes based on goal setting, forecasting, and planning in the context of informatization of society. The object of study there is a process of forming the state system of strategic planning of national security of Ukraine. The relevance of this study is due to the need for legal regulation and improvement of the state system of strategic planning of national security of Ukraine. To achieve the goal of the study special scientific methods of legal knowledge were used. The results of the analysis showed that ensuring national security must rely on the principle of systematization, which means that the security and defense sector of Ukraine is considered as a single object of forecasting and planning. This study substantiates the main directions of systemic reform of the security and defense sector, which have been carried out in Ukraine to ensure the protection of the constitutional order, sovereignty, territorial integrity of the state in the face of armed aggression. The priorities should be implemented through key tasks, such as the establishment of a comprehensive strategic analysis of military threats to Ukraine's national security, coordination of intelligence activities, development of joint intelligence capabilities of the defense forces to obtain complete and reliable warning information for timely decision-making guaranteeing the military security of the state. Keywords: national security, state system, strategic planning, national security strategy, threats to the public administration system, informatization of society.

ROMANIAN ARMY`S JOINT FIRE SUPPORT APPROACH AND ITS IMPLICATIONS IN CONDUCTING MILITARY OPERATIONS

In this paper I wanted to highlight those characteristic elements regarding the joint fire support In this paper I wanted to highlight those characteristic elements regarding the joint fire support concept as they are presented and detailed in our standing national doctrine and field manuals. From a national point of view, joint fire support is described as being the use of specific fire support platforms – land, maritime or aerial – that have the ability to execute indirect fire to generate planned effects on ground targets in direct support for land force operations. This is somewhat a limited perspective that comes, in my opinion, from our current level of equipment with modern fire support systems. The increasing need for modernizing armed forces capabilities and for implementing ongoing and future army equipment programs determine from a conceptual and a doctrinal point of view an adaptation regarding how these new structures and capabilities can best contribute to military operation’s success. Equipping the Romanian Army with modern systems designed to engage targets from distant standoff positions offers new possibilities for the joint fire support system, possibilities that require a new level of integration and synchronization for activities and actions that specialized armed structures, existing at the component level or attached from higher, need to execute in order to properlyengage and exploit these fire support capabilities concept as they are presented and detailed in our standing national doctrine and field manuals. From a national point of view, joint fire support is described as being the use of specific fire support platforms – land, maritimeor aerial – that have the ability to execute indirect fire to generate planned effects on ground targets in direct support for land force operations. This is somewhat a limited perspective that comes, in my opinion, from our current level of equipment with modern fire support systems. The increasing need for modernizing armed forces capabilities and for implementing ongoing and future army equipment programs determine from a conceptual and a doctrinal point of view an adaptation regarding how these new structures and capabilities can bestcontribute to military operation’s success. Equipping the Romanian Army with modern systems designed to engage targets from distant standoff positions offers new possibilities for the joint fire support system, possibilities that require a new level of integration and synchronization for activities and actions that specialized armed structures, existing at the component level or attached from higher, need to execute in order to properly engage and exploit these fire support capabilities

Use of agent-based modeling to model intermediate force capabilities in (counter)mobility crowd scenarios

In this paper, we use an agent-based model (ABM) to run (counter)mobility scenarios to explore which characteristics of intermediate force capabilities (IFC) are relevant to these, and how they can affect outcomes in gray zone conflicts. Using an ABM called Map-Aware Non-Uniform Automata (MANA), developed by the New Zealand Defense Technology Agency, we implemented two scenarios where the friendly forces’ mobility was limited by large groups of civilians. Then, we employed data farming and analytics methods to analyze the data and identify key parameters influencing the outcomes. The main parameters appeared to be the IFC Range, Power (a measure of the duration of the effect), and Crowd Density. Future research could include a wide range of mobility scenarios and possibly a more detailed IFC representation.

Familial Factors Influencing Creativity among Married Employees of Financial Technology Organisations in Cotonou: Mediatory Role of Proness to Divorce

bstract In the face of a complex and changing external environment, employee creativity has evolved into the driving force and core competitive capability required for most organizations to thrive in their enterprise. Most studies conducted on employees’ creativity were mainly from the perspective of organizational factors rather than personal factors. Therefore, this study investigated the prediction of employee’s creativity from familial factors (commitment to marriage, marital satisfaction, familism, and religiosity) and how proneness to divorce could mediate the strength of this relationship among married employees in FinTech organisations in Cotonou, Benin Republic. The study was cross-sectional in approach that adopted the ex-post facto design, in which a questionnaire measuring social-demographic variables, marital commitment, marital satisfaction, familism, proneness to divorce, religiosity and creativity was administered to 190 consenting married employees in FinTech, using convenience sampling technique. Pearson product moment correlation, multiple regression, and t-test for independent samples were used to test the hypotheses at p&lt;.01. The participants’ ages ranged from 26 to 63 years old, with a Mage of 36±5.47 years. Results obtained revealed employees’ creativity has a significant positive relationship with marital commitment (r=0.437, p&lt;0.01) but a significant inverse relationship with divorce proneness (r=- 0.706, p&lt;0.01), marital satisfaction (r=-0.257, p&lt;0.01), religiosity (r=-0.561, p&lt;0.01). Further analysis revealed that all predictor variables (commitment to marriage, familism, marital satisfaction, &amp; religiosity) significantly related to creativity among married employees. Meaning that the extents of correlations between commitment to marriage, familism, marital satisfaction, religiosity and creativity were significantly lowered by the inclusion of proneness to divorce as a mediator. The results of this study, which show the significance of proneness to divorce in tying familial variables and workplace outcomes, give a framework for understanding how familial factors contribute to diversity in degrees of creativity for organizational efficiency

Security Force Assistance Brigades and US Indo-Pacific Command Multi-domain Competition

Security force assistance brigades can enable multi-domain convergence in competition in the US Indo-Pacific Command. Rather than focusing on conventional Joint force capabilities, this article analyzes recent US Army operational experience in security force assistance and security cooperation in US Indo-Pacific Command and identifies capability gaps and opportunities for competition. Finally, military leadership and policymakers will find recommendations on how US Army security force assistance and security cooperation can shape environments and deter conflict in the US Indo-Pacific Command area of responsibility.

Effects of changes in optimal muscle fibre length in the biceps femoris long head on muscle force during the late swing phase of maximal speed sprinting: a simulation study

ABSTRACT Hamstring strain injuries would frequently occur during the late swing phase of sprinting, while increasing biceps femoris long head’s (BFlh) fascicle length induced by eccentric contraction exercises can reduce the risk of strain injuries. Thus, using a musculoskeletal modelling simulation, we examined how manipulating BFlh optimal muscle fibre length would change muscle force during the late swing phase of sprinting for providing knowledge preventing hamstring strain injuries. A motion capture system was used to collect kinematic data from 40 male athletes during maximal speed sprinting. Muscle force and force-generating capabilities determined by force-length-velocity properties were estimated with three BFlh optimal muscle fibre lengths (90%, 110% and 120%), which were perturbed from the nominal (100%). During the late swing phase of sprinting, the muscle force and force-generating capabilities, induced by the force-length property rather than the force-velocity property, were increased by increases in BFlh optimal muscle fibre length. Moreover, magnitudes of the simulated increases in muscle force and force-generating capabilities were correlated with the peak BFlh muscle-tendon unit length. These results demonstrate that lengthening BFlh optimal muscle fibre might increase muscle force during the late swing phase, and the magnitude of increment would be associated with increasing muscle-tendon unit length.

Deployment Optimization of Defense Stations in an Attack-Defense Aerial War Game

An attack–defense aerial war game is developed to maximize the capability of defense forces in protecting a target area from an attack force. The attack force is composed of multiple attack stations in slant or pincer formation, and each attack station can launch multiple attackers against the defense force. The defense force is composed of one major post, two minor posts, and multiple defense stations, and each defense station is equipped with multiple interceptors against the approaching attackers. Four optional defense goals are proposed to guide the deployment of defense stations. A particle swarm optimization (PSO) algorithm is applied to acquire an optimal deployment plan of all the defense stations, under a specific defense goal. Multiple games are played with the optimal deployment plan, and the results are analyzed statistically. Interesting outlier cases are also inspected to gain more insights on the nature of the games.

Improving the Force Display of Haptic Device Based on Gravity Compensation for Surgical Robotics

Haptic devices are applied as masters to provide force displays for telemedicinal robots. Gravity compensation has been proven to be crucial for the accuracy and capability of force displays, which are critical for haptic devices to assist operators. Therefore, the existing method suffers from an unsatisfactory effect, a complex implementation, and low efficiency. In this paper, an approach combining active and passive gravity compensation is proposed to improve the performance of a force display. The passive compensation is conducted by counterweights fixed with the moving platform and pantographs to offset most of the gravity and reduce the loads of the motors, while the peak capability of the force display is enhanced. The required weight is optimized by a multi-objective genetic algorithm in terms of the maximum torque of the motors in the global workspace. As a supplement, the residual gravity is eliminated by active compensation to extend the accuracy of the force display. The balancing forces in the discretized workspace are entirely calibrated, and the required force for the arbitrary configuration is calculated by interpolations. The decisions regarding the algorithm parameters are also discussed to achieve a compromise between the effect and elapsed time. Finally, the prototype with a compensation mechanism is implemented and experiments are carried out to verify the performance of the proposed method. The results show that the peak capability of the force display is enhanced by 45.43% and the maximum deviation is lowered to 0.6 N.