Bar Mechanism Research Articles

Kinematic analysis applied to a solar tracker driven by a 4-bar mechanism

This paper presents the kinematic analysis of the eccentric crank-slider and crank-rocker mechanisms applied to control the 1-DOF in a solar tracker focused on improving the conversion of solar energy into electrical energy. The mechanisms for its construction and the kinematic equations that allow to know the state that keeps the movement in the working space of the tracker and its comparative analysis between them are presented. Finally, the construction to scale with 3D printing is shown to validate the functionality of each of the 4-bar systems.

Thread plate posture analysis for screw rolling adjustment design

Abstract This research focuses on process design of the adjustment of movable thread plate and fixed thread plate in the screw rolling machine during production. By observing some key dimensions of the threaded screw, one can determine the movement amount and the rotation direction of the adjustment screw bars mechanism of the fixed thread plate that required for the specified size of this type of screw. One establishes a relationship from the adjustment of the screw bars mechanism to the fixed thread plate posture. It can be seen that the formed screw size deviations will lead the machine operator to adopt one of the proposed process to achieve the posture adjustment of the fixed thread plate. While the screw specification deviations do not conform to the standard ones, the operator just need to find out the error type of the formed screw and measures its specification to follow one of the proposed formulas, then the wrong thread plate posture can be modified to the correct posture under operator’s adjustment. The method addressed in this research can not only reduce the operational difficulty of screw thread rolling machine but also can reduce the trial-and-error processes in traditional operation methods.

Sowing depth stability analysis and test verification of no-tillage planter parallel 4-bar row unit

The sowing depth stability and consistency of the no-tillage planter, particularly the high-speed operation, are poor. A reason for this is that the structure and parameter selection of no-tillage planter row unit profiling mechanism are unreasonable. The stability and consistency of sowing depth is beneficial when the upper and lower links of the parallel 4-bar profiling mechanism (PFPM) are parallel to the ground, but this principle is not satisfied on the uneven no-till soil. To improve the stability of gauge wheels downforce (GWD) and sowing depth of no-tillage planter row unit. The variation law of spring additional downforce (SAD) with tilt angle of parallel 4-bar profiling mechanism (PFPM) and connection offset of spring is discussed by constructing the steady state analysis matrix equation of PFPM. Additionally, the influence of tilt angle of PFPM and SAD on the stability of the sowing depth was analyzed. Based on the single factor control variable test method, bench and field tests were conducted. The test results show that the SAD increases nonlinearly with the increase in the degree of tilt of PFPM from downward to upward. Under the condition that four springs are installed and the tilt angle of PFPM is between (−20°–20°), the maximum SAD is 485.95 N, 1236.64 N, and 2258.05 N when the spring connection offset is 44 mm, 79 mm, and 115 mm, respectively. When the tilt angle is 8° upward, the GWD increases by 429 N, 575 N, and 984 N, GWD stability increases by 42.31 %, 56.16 %, and 50.29 %, and ditching depth stability increases by 30.00 %, 12.50 %, and 30.00 % compared with that of the control group at the sowing speed of 8, 10, and 12 km/h, respectively. At the sowing speed of 10 km/h, when the PFPM is operated with spring-free and additional springs, the average GWD increases by 353 N, and the stability of GWD and ditching depth increases by 34.38 % and 20.00 %, respectively. The results showed that the tilt upward of PFPM and SAD were beneficial to improve the stability of the GWD and sowing depth of the no-tillage planter row unit. The results not only verify the correctness of theoretical analysis, but also provide theoretical basis for the design and application adjustment of high-speed no-tillage planter.

Corrosion behavior of steel bar in magnesium oxysulfide cement-based materials: The role of chloride and nitrite

Magnesium oxysulfide (MOS) cement has emerged as a promising cementitious material due to the high strength and excellent durability, but research on its rust inhibition remains limited. In this study, the chloride and nitrite were introduced in the MOS cement composites, aiming to investigate the corrosion properties and reveal the rust inhibition mechanism of steel bar under different W/C ratio. Experimental results show that the corrosion area ratios reach the largest value of approximately 98% and the lowest value of approximately 3%, respectively, as the chloride and nitrite contents increase to 2%. Compared with chloride, the effect of W/C ratio on the mass loss of steel bar is gradually weakened when the nitrite content is larger than 0.5%. Based on the natural potential, the change of corrosion degree mainly occurs after 28d. In addition, the corrosion potential of steel bar decreases and corrosion rate increases with the increase of chloride content in MOS cement composites. Conversely, the presence of Mg(NO2)2 from nitrite engenders an opposite effect. Besides, the increase of W/C ratio results in higher electrochemical parameters. At this time, the rust inhibition mechanism is revealed based on the micro-structure analysis.

Meso-scale Study of Bond Behavior between Ribbed Steel Rebar and Fiber-reinforced Cementitious Composite Considering Rebar Rib Geometry

This study aims to develop a meso-scale finite element approach to investigate the pull-out behavior of ribbed steel rebar and fiber-reinforced cement composites. We considered separately the three phases of steel fibers, cement composite matrix, and rebar within the meso-scale finite element model. A random distribution of fibers was generated in the matrix based on the geometric characteristics of the fibers and their volume fraction. By employing the interfacial transition zone (ITZ) model, the interaction between rebar and fibers with cement composite was simulated. Experimental pull-out tests were conducted to determine the parameters of the model. A meso-scale finite element model was validated and the effect of rebar diameter and fiber volume fraction on the bond behavior of rebar with fiber-reinforced cement composites was examined. In accordance with the experimental results, the bond-slip curve obtained with the meso-scale finite element model can be divided into five areas: non-slip, slight slip, splitting, decreasing, and residual. Additionally, it can be observed that fiber-free cement composites fail by splitting, whereas specimens containing fibers fail by sliding. This numerical model is therefore able to predict and estimate the influence of a variety of parameters on the pull-out response between fiber-reinforced cement composite and ribbed bar and failure mechanisms without the need for expensive and time-consuming testing.

The effect of friction characteristics on electromagnetic impact deformation mechanism of 2A10 aluminum alloy bars

Purpose The purpose objective of this study is to identify the friction coefficient and friction effect in electromagnetic upsetting (EMU) high-speed forming process. Design/methodology/approach Based on numerical simulation and upsetting experiment of 2A10 aluminum alloy bar, the friction coefficient between contact surfaces is obtained by combining the fitting displacement distribution function and the electromagnetic-mechanical coupling numerical model, and the influence of friction effect is analyzed. Findings The maximum impact velocity and acceleration during EMU are 13.9 m/s and −3.3 × 106 m/s2, respectively, and the maximum strain rate is 7700 s−1. The functional distribution relationship between friction coefficient combination (FS, FD) and characteristic parameters [upper diameter (D1) and middle diameter (D2)] is established. The values of FS and FD are 0.1402 and 0.0931, respectively, and the maximum relative error is 2.39%. By analyzing the distribution of equivalent stress and strain, it is found that plastic deformation has obvious zoning characteristics and there is serious failure concentration in the strong shear zone. Originality/value Friction coefficient significantly affects stress or strain distributions in material forming process, but it is difficult to obtain friction coefficients through experimental tests in the high-speed forming process. In this paper, a multi-field coupling numerical model is proposed to determine friction coefficients and applied to the electromagnetic impact loading process (a high-speed forming process). Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2024-0154/

Mechanism Analysis and Optimization Design of Exoskeleton Robot with Non-Circular Gear–Pentabar Mechanism

To address the complex structure of existing rod mechanism exoskeleton robots and the difficulty in solving the motion trajectory of multi−rod mechanisms, an exoskeleton knee robot with a differential non−circular gear–pentarod mechanism is designed based on non−circular gears with arbitrary transmission ratios to constrain the degrees of freedom of the R-para-rod mechanism. In this study, the kinematic model of a non-circular gear–five−rod mechanism is established based on motion mapping theory by obtaining the normal motion positions of the human lower limb. An optimization design software for the non-circular gear–five−rod mechanism is developed using the MATLAB 2018b visualization platform, with the non−circular active gear as the sole input variable. A set of ideal parameters is obtained through parameter adjustment and optimal parameter selection, and the corresponding trajectories are compared with human trajectories. The three−dimensional model of the mechanism is established according to the obtained parameters, and the motion simulation of the non−circular gear–five−bar mechanism demonstrates that the mechanism can better reproduce the expected human knee joint motion posture, meeting the working requirements of an exoskeleton knee robot.

Research on active load reducing optimization strategy for 6061Al low cycle fatigue cropping process based on crack propagation mode transformation

Low cycle fatigue cropping technology is a new type of cropping technology with advantages such as no chip waste and low load need. Numerous studies have shown that increasing the fatigue frequency or increasing the displacement load can improve the cropping efficiency, but at the same time, it will reduce the quality of the cross-section and cannot achieve a balance between high efficiency and high quality of cross-section. In response to this issue, this paper found the phenomenon of transition of fracture modes (from fatigue mode to tensile fracture mode) of 6061Al material in LCFC process, and proposed the Active Load Reducing Optimization Strategy for 6061Al in LCFC, which achieves a significant improvement in quality of cross-section with a slight loss of cropping efficiency. Firstly, this paper studied the crack fracture mechanism of 6061Al bar under different displacement loads in the LCFC process. It was found that the transition of crack propagation mode in 6061Al- LCFC process was the main reason for the increase in cross-section roughness. The crack propagation mode changed from fatigue propagation to tensile fracture propagation during the LCFC process, and the roughness of the area significantly increased under the tensile fracture propagation mode. Further research has found that the fundamental reason for the contradiction between the cropping efficiency and section quality of 6061Al is the change in time of crack propagation mode transition and tensile fracture zone area under different displacement loads. Finally, the LCFC process was modeled in a time dimension using acoustic emission(AE) technology, and it was divided into three stages according to the AE signals and the fracture mechanism. As a result, an active load reducing optimization strategy for LCFC process was developed to delay the occurrence of tensile fracture propagation modes. Experiments have shown that compared to the traditional LCFC cropping strategy using constant displacement loads, the active load reducing strategy proposed in this paper can reduce the proportion of tensile fracture area, achieve a significant improvement in quality of cross-section with a slight loss of cropping efficiency, thus achieving a balance between efficiency and section quality to some extent. At the same time, an LCFC process section quality efficiency evaluation index with dual weights of efficiency and section quality has been proposed, which can assist in selecting LCFC active load reducing strategy parameters with consideration of efficiency and section quality weights.

Durability of concrete-encapsulated GFRP bars subjected to seawater immersion

Glass fiber reinforce polymer (GFRP) bars have better durability than traditional steel bars, but there are few studies on their long-term performance in actual service environments especially the marine environment. To investigate the durability of GFRP bars used in cross-sea bridges, this research delves into the performance of 132 such bars, spanning diameters of 10, 12, 16, and 25 mm, in an environment that closely mimics real-world condition. The GFRP bars, encapsulated in concrete, were submerged in seawater solution, maintained at either room temperature or 60°C, for periods spanning from 0 to 183 days. Then the tensile strength and elastic modulus degradation of GFRP bars were investigated by tensile tests. Scanning electron microscope (SEM) was also used to analyze the micro-degradation mechanism of GFRP bars. In addition, this paper compares the four existing models for predicting long-term mechanical properties of GFRP bars with the experimental data, so as to determine the formulas and methods to be used in the design. The result shows that the elastic modulus of GFRP bars after 183 days of immersion in concrete pore solution was almost unchanged while the tensile strength decreased significantly. Among them, the tensile strength of 10 mm diameter GFRP bars decreased by 41.52 %, after 183 days of immersion at high temperature (60°C). The SEM method revealed that the main cause of such phenomena was the weakening of the bond between the fibers and matrix, which led to a decrease in the interface property. Finally, by fitting and comparing the relationship between the test data and the existing prediction models for the long-term mechanical properties of GFRP bars, the residual tensile strength of GFRP bars used in the actual project of Yanzhou Bridge for 100 years was predicted according to the optimal prediction model, i.e. the Serb model, and the results showed that the residual strength of GFRP bars is able to meet the current standard requirement.

Design, preparation and mechanical properties of novel glass fiber reinforced polypropylene bending bars

Fiber reinforced thermoplastic composite bars offered the advantages of repeated molding, high toughness, and recyclability, making them a promising alternative to steel bars. For the stirrups applications in concrete structures, it was essential to develop efficient bending technologies for producing high-quality thermoplastic bending bars. In the present paper, the bending properties of glass fiber reinforced polypropylene (GFRPP) composite bars were investigated by experimental and theoretical methods. A novel bending fixture of GFRPP bars was specifically designed for GFRPP bars to ensure the reliable bending of the bars. Finite element simulation was employed to analyze the stress distribution of GFRPP bars, providing valuable insights into their mechanical behavior. Additionally, a bending strength model was developed based on the material mechanics, offering a theoretical framework for understanding and predicting the bending strength of GFRPP bars. Finally, the bending mechanism of bars was further revealed according to experimental and theoretical findings. The results of the study demonstrated that the specially designed bending fixture was successful in minimizing damage to the bending section of the GFRPP bars, leading to a significant improvement in bending strength retention of up to 43.2 %. Furthermore, the theoretical results and experimental test have a good agreement in terms of stress distribution and failure mode. The maximum strain in the transition zone between the straight section and the bending section of the GFRPP bars was nearly double that of the straight section at the same stress levels. With the increase of bending radius to diameter ratio from 3.0 to 7.0, the tensile strength of GFRPP bending bars increased by ∼7.9 %. The study identified the transition area between the bending section and straight section of GFRPP bars as the most critical failure point. The strength degradation mechanism during the bending were attributed to the shrinkage and torsion of inner fibers owing to the compression caused the local stress concentration, which caused the inner resin matrix to crack and interface debonding of fiber/resin, leading to the premature tensile failure.

Bond performance of NSM FRP–concrete interfaces with epoxy under chloride‐salt conditioned environments

AbstractConcrete in coastal areas is susceptible to structural damage caused by corrosion and expansion of reinforcement. Near‐surface mounted (NSM) fiber‐reinforced polymer (FRP) bars have become effective for strengthening damaged reinforced concrete structures. The bonding performance of NSM FRP bars in concrete is a key factor limiting their application and promotion in civil engineering. In this study, the influences of the conditioned environment, such as the chloride salt concentration, immersion time, and bond length of the FRP bar, on the bonding performance were investigated experimentally. First, material properties in a conditioned environment were studied. Subsequently, the failure mode, bond stress–slip curve, and bond strength of the NSM FRP bar in concrete were investigated. Finally, the microstructure and chemical composition of the materials were revealed using scanning electron microscopy and energy‐dispersive spectroscopy (EDS) images of the materials under environmental conditions. The transfer mechanism of NSM FRP bars in concrete with epoxy was revealed. The results showed that the failure modes of the pullout specimens can be divided into epoxy splitting failure and basalt fiber‐reinforced polymer (BFRP) pulling failure. The chloride‐salt concentration was a critical factor affecting the bond properties, and the longer the bond length, the lower the bond strength. The microstructure clearly shows that the degradation of the bonding behavior at the interface of the NSM FRP bar in concrete in a conditioned environment is attributable primarily to the resin damage of the epoxy, resulting in pit corrosion. There was no significant damage to the fibers in the FRP bar, and the degradation was primarily due to resin matrix damage and interfacial debonding. The EDS results showed that the degradation of the epoxy resin and BFRP bars was caused by CO bond and SiO bond fractures, respectively.

Research and simulation analysis of crack failure mechanism of conductor spacer bar in ±800 kV converter station

The cracking of the conductor spacer bar in a ±800 kV converter station was detected and simulated to study the cause of failure. By means of penetration detection, fracture macroscopic inspection and metallographic inspection, it can be found that there are some casting defects such as segregation, pinhole and intergranular micro-crack in the chuck microstructure of the spacer bar, and the fatigue fracture occurs under the action of alternating stress. Through the structural simulation analysis, it can be concluded that the spacer rod body and the joint of the chuck have a structural mutation, which causes stress concentration and leads to the fracture of the spacer rod. Finally, suggestions are put forward to improve the design, manufacture and installation process of spacer rods to prevent similar failures from happening again and ensure the safe operation of the power grid.

Dynamical influence of a central massive object on double-barred galaxies: self-destruction mechanism of secondary bars

Abstract Double-barred galaxies exhibit sub-kiloparsec secondary stellar bars that are crucial for channeling gases towards a central massive object (CMO) such as a supermassive black hole or a nuclear star cluster. Recent N-body simulations have uncovered a novel galaxy evolution scenario wherein the mass of the CMO increases owing to the secondary bar, resulting in the eventual destruction of the latter. Consequently, the CMO mass growth halts, thus suggesting a maximum CMO mass of ≈10−3 of the stellar mass of the galaxy. This study focuses on backbone orbit families, particularly double-frequency orbits, within double-barred galaxies. Consequently, the dynamic influence of a CMO on these orbits is investigated. The results of the study reveal the emergence of a new orbital resonance within the central region of the galaxy upon the introduction of a CMO. Orbits subjected to this resonance become chaotic and fail to support the secondary bar, ultimately resulting in the destruction of the entire structure. This is partly because of the inability of the secondary bar to obtain support from the newly generated orbit families following the appearance of resonance. Through the estimation of the condition of secondary bar destruction in realistic double-bar galaxies with varying pattern speeds, the results of the study establish that such destruction occurred when the CMO mass reached ≈10−3 of the galaxy mass. Furthermore, a physical explanation of the galaxy evolution scenario is provided, thereby elucidating the interaction between the CMO and the secondary bar. The understanding of the co-evolution of the secondary bar and the CMO, based on stellar orbital motion, is a crucial step towards future observational studies of stars within the bulge of the Milky Way.

Contributions to the synthesis of the windshield wiper mechanism with one rocker-slider blade

The paper deals with synthesis of the windshield wiper mechanism with one rocker-slider blade. Starting from the kinematic scheme of the constructive model designed by Mercedes-Benz motor vehicle company, a structure analysis on this complex mechanism consisting of three kinematic chains, of which two are articulated bar mechanisms and one is planetary mechanism, has been accomplished. The novelty of this paper consists in the presentation of an optimum synthesis method of the planar bar mechanism in two variants for the wiper blade driving. The first variant is a planar 4-bar mechanism type crank-rocker where the cosines theorem has been applied in order to obtain the lengths of the coupler and the crank. The second analyzed variant is a bi-contour linkage consisting of two 4-bar mechanisms linked in series. Further, the calculation of the planetary gear angular velocity on the complex mechanism with dyadic kinematic chains has been achieved. In order to do this, the immobilization of the planetary carrier method has been applied. Finally, the geometry of the driven linkage of the wiper mechanism type crank-slider which has two mobilities has been studied. A vector equation has been written in order to obtain the length of the variable blade.

Design of a New Glass Cleaning Robot

Improve the various abilities of glass cleaning robots, such as climbing ability and obstacle crossing ability at any angle, change the traditional movement mode of robots, and enable them to perform obstacle free movement in three-dimensional space. Taking inspiration from the quadruped movement of geckos, the UG software in mechanical CAD/CAM is used to simulate the structure of a glass cleaning robot for gait planning and structural design. By studying the force situation, the dimensions of the four bar mechanism and the size of the suction cup of the vacuum suction cup quadruped glass cleaning robot were derived. The structural design diagram was drawn, and its operating trajectory and mode were explained. Create post-processing through Postbuilder, conduct comprehensive testing and simulation to ensure accuracy before processing its components. The calculation shows that the thigh step distance within one cycle is 89.83 mm, and the calf step distance is 3.11 mm. So, the total step distance of a single leg in one cycle is 92.94 mm. Based on this, a top-down modeling approach was adopted, and assembly methods, connection methods, and driving methods were set in the simulation. The cosine function was used to control the motion trajectory of the legs. This design effectively simulates the motion of geckos. In future research, we will continue to focus on the dynamic trajectory of the robot's tail, in order to enable the robot to adjust its posture through its tail under microgravity and make the motion of the gecko like robot more flexible.

烟草打塘-移栽一体化装置的设计与优化

To overcome inadequate functional integration, irregular pits, and insufficient agricultural machinery and agronomy in tobacco seedling transplanting equipment under film, a digging transplanting integrated machine was built. The machine uses parallel four-bar mechanism. The excavation equipment uses conical spiral blades. Using the trajectory approach, the four bar mechanism's fundamental parameters can be reversed. This method meets the requirements for coordinated excavation and transplantation. Mechanical study of soil units determines upward movement characteristics. Additionally, spiral angle, spiral blade outer diameter, and spiral blade speed are quantified to affect soil movement. The range of factors is derived. Based on three factors binary regression orthogonal combination simulated optimization experiment, a discrete element analysis was performed to enhance parameters. Experimental factors optimized include a spiral angle of 19°, a spiral blade diameter of 378 mm, and a rotational speed of 258 rpm. The two optimized test indicators are: a 193 mm hole depth and 350 mm hole diameter. The improved results were verified by field validation studies using a 191 mm hole depth and 347 mm hole diameter. The simulation optimization results and field validation experiment results are very similar. This study provides a technical basis for tobacco farming concurrent drilling and transplanting research.

Dynamic Monkey Bar Mechanism of Superionic Li‐ion Transport in LiTaCl6

AbstractThe LiTaCl6 solid electrolyte has the lowest activation energy of ionic conduction at ambient conditions (0.165 eV), with a record high ionic conductivity for a ternary compound (11 mS cm−1). However, the mechanism has been unclear. We train machine‐learning force fields (MLFF) on ab initio molecular dynamics (AIMD) data on‐the‐fly and perform MLFF MD simulations of AIMD quality up to the nanosecond scale at the experimental temperatures, which allows us to predict accurate activation energy for Li‐ion diffusion (at 0.164 eV). Detailed analyses of trajectories and vibrational density of states show that the large‐amplitude vibrations of Cl− ions in TaCl6− enable the fast Li‐ion transport by allowing dynamic breaking and reforming of Li−Cl bonds across the space in between the TaCl6− octahedra. We term this process the dynamic‐monkey‐bar mechanism of superionic Li+ transport which could aid the development of new solid electrolytes for all‐solid‐state lithium batteries.

Dynamic Monkey Bar Mechanism of Superionic Li-ion Transport in LiTaCl6.

The LiTaCl6 solid electrolyte has the lowest activation energy of ionic conduction at ambient conditions (0.165 eV), with a record high ionic conductivity for a ternary compound (11 mS cm-1 ). However, the mechanism has been unclear. We train machine-learning force fields (MLFF) on ab initio molecular dynamics (AIMD) data on-the-fly and perform MLFF MD simulations of AIMD quality up to the nanosecond scale at the experimental temperatures, which allows us to predict accurate activation energy for Li-ion diffusion (at 0.164 eV). Detailed analyses of trajectories and vibrational density of states show that the large-amplitude vibrations of Cl- ions in TaCl6 - enable the fast Li-ion transport by allowing dynamic breaking and reforming of Li-Cl bonds across the space in between the TaCl6 - octahedra. We term this process the dynamic-monkey-bar mechanism of superionic Li+ transport which could aid the development of new solid electrolytes for all-solid-state lithium batteries.

Sistem for variable pitch vertical axis wind turbine

Climate changes and their effect worldwide point toward high need of renewable energy resources exploitation and, consequently, adequate policies on regulation for efficient energy consumption. Wind has been used since ancient times for producing energy and this is why research on wind turbine design and performances has been carried on since. This article is aimed to present new mechanical system for variable pitch vertical axis four blades wind turbine. The pitch angle varies depending on wind flow direction due to cam and follower, linked to a four bar mechanism.

Force-adjustable parallel-occlusion grasper.

During laparoscopic surgery, the operating surgeon grasps sections of the gastrointestinal tract (GIT), including delicate structures, with long (270mm) 5mm diameter graspers. These grasping instruments increase the risk of iatrogenic damage due to crushing of the grasped tissue. This risk is increased significantly by diseases such as bacterial peritonitis and inflammatory bowel disease and reduced but not abolished by using parallel-closing laparoscopic instruments. This study describes the design and laboratory testing of fully developed and tested smart graspers capable of reducing the grasping force used for inflamed tissues and hollow viscera. In an ISO 13485-certified mechanical laboratory and CAD machine workshop, the authors have designed, developed, and evaluated a smart gasper capable of exerting a preselected uniform grasping force on the gastrointestinal tract and other structures/ tissues, through a mechanism incorporated in the handle of the instrument. This enables the control and graded reduction of the grasping force by the incorporation of a compression spring. The authors named the new instrument the force-adjustable parallel-occlusion grasper (FA-POG) because, in addition to applying a uniform force on the grasped bowel/tissue, it also enables the surgeon to select the force before grasping, depending on its physical condition, and pathological state. FA-POG differs from traditional pinch-occlusion grasper in two respects: it exerts a uniform force on the grasped tissue/bowel and enables the operating surgeon to select and apply a predetermined uniform grasping force, ranging from 1 to 5 N, depending on the pathological condition of the bowel/structure. The ISO 13485-certified and fully developed prototype has been subjected to various grasping in-vitro tests using freshly harvested porcine small-bowel segments obtained from a local abattoir, using Instron tensiometry. The authors designed and α/β tested a parallel-occlusion gasper that enables the operating surgeon to select the force before grasping. This grasper design consists of end-effectors jaws with a 4-bar linkage mechanism for wide, uniform parallel-occlusion force, surpassing traditional scissor-type laparoscopic graspers. It incorporates a force-level controller knob, based on a spring-loaded mechanism, enabling surgeon-preselected grip force to prevent excessive grasping. The authors validated the design experimentally using porcine small-bowel segments, optimizing teeth for maximum grip friction to minimize slippage.