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Biomechanical properties of bones and fixators are important. The aim of this study was to develop a new device to simulate the real mechanical environment and to evaluate biomechanical properties of the bone with a fixation device, including the static force and the fatigue characters.

In this paper, the device is mainly composed of three parts: pull-pressure transmission system, bending force applying system and torsion applying system, which can successfully simulate the pre-introduced pull-pressure force, bending force and torsion force, respectively. To prove the feasibility of the design, theoretical analysis is used. It is concluded from the simulated result that this scheme of design can successfully satisfy the request of the evaluation.

Finally, on the basis of the force sensor calibration, the static force experiment and fatigue experiment are carried out using the tibia of the sheep as the specimen. It is concluded from the result that the relationship between the micro displacement and the applied axial force is nearly linear. Under the condition of 1 Hz in frequency, 500 N in loading force and 18,000 reciprocating cycles, the bone fixator can still be in good condition, which proves the feasibility of the design.

Biomechanical properties of bones and fixators are studied by researchers. However, few simulate a real force environment and combine forces in different directions. So a novel system is designed and fabricated to evaluate the biomechanical properties of the bones and fixators. Results of the experiments show that this new system is reliable and stable, which can support the biomechanical study and clinical treatment.

The study of vascular mechanics is important. The purpose of this paper is to present an apparatus to measure the biomechanical properties of blood vessels, which can be used for tensile test and fatigue test.

This equipment consists of a mechanical test platform, a hardware circuit based on FPGA and control software. The torque generated by stepper motor is converted to axial force by ball screw, and the vascular specimen is stretched axially. The tension is measured by a load cell, and the displacement is recorded by a grating displacement sensor.

According to the results of calibration experiment and stability experiment, the linearity error of the system is 0.251, the hysteresis error is 0.047, the repeatability error is 0.185, the comprehensive error is 0.315 and the standard deviation of the output is less than 0.01 N. A test of animal vascular mechanical properties was carried out, and the results are consistent with the theory.

This apparatus is designed to measure biomechanical properties of blood vessels, and the results of experiments indicate that it is stable and reliable. This work is valuable for studying vascular disease and testing artificial blood vessels.

The purpose of this paper is to design and implement a new manufacturing process for biomedical products by removing an electro‐polishing (EP) operation. The research was performed in a major North American orthopedic industry.

Value stream mapping is used to analyze and identify the waste in the current manufacturing process of bone screw. Upon formulation of new (to‐be) process, it has been validated to meet the regulatory requirements for the products through autoclave, endotoxin level, and biomechanical tests. Statistical tests are performed to compare the EP versus non‐EP process.

The study has shown that the EP operation was not only redundant to bone screw manufacturing but also created other problems such as quality and production delays. The overall production lead time of the screws has been reduced from 17 to 4.5 days.

Scope of the pilot study was limited to stainless steel screw. In future, the company plans to perform similar studies on other material types.

The EP operation is very common in the orthopedic industry. However, as found in this paper, it is not required for every component. The bone screw case study presented in the paper offers a huge saving for the company by eliminating a “wasteful” activity from the manufacturing process.

Biomedical products pose unique challenges to the process optimization efforts because of their stringent government and industry requirements. This paper provides an original case study of design, validation, and testing of an improved manufacturing process for a biomedical product.

The purpose of this paper is to apply firm aspiration theory to explore how firms respond to government product ratings.

Longitudinal examination of nine automobile manufacturers during National Highway Traffic and Safety Administration crash tests in the USA.

Firms take specific external actions to influence the political mechanisms that support ranking schemes when product ratings are below those of rivals and when previously highly rated products decline. In addition, firms receiving rankings above those of their competitors are found to be less likely to take such action, even when their overall ratings declined. Similarly, firms seeing improvements in previously low-rated products will take fewer actions aimed at influencing the political mechanisms that support rating schemes.

The primary contribution of this research is in establishing when firm product ratings will result in actions to influence external ratings criteria. Previous research has shown that firms respond to organizational ratings by taking action aimed at improving subsequent performance. The current research builds on such work by applying aspiration theory in an effort to predict and explain when and why certain ratings will attract firm attention to the external mechanisms that support such ratings.

This study aims to examine conditions in which firm political market performance is associated with firm efforts to influence regulatory outcomes. Applying measures of political market performance based on firm performance in government enforcement actions and a firm’s ability to obtain favorable political outcomes, the authors make the case that political market performance is a key part of competitive political markets, which is associated with particular types of firm efforts to influence policy.

Longitudinal examination of nine automobile manufacturers during National Highway Traffic and Safety Administration crash tests reveals that firm performance in government enforcement activities is associated with greater efforts to cooperate with political suppliers, while declining firm performance in efforts to influence political outcomes is associated with increased firm opposition to political supplier actions.

Firm performance in government enforcement activities is associated with greater efforts to cooperate with political suppliers, while declining firm performance in efforts to influence political outcomes is associated with increased firm opposition to political supplier actions.

Performance in regulatory enforcement results in increased firm actions to engage regulators in the policy-making process, while performance in obtaining desired policy outcomes is associated with a greater focus on opposition to proposed standards. These results suggest that political demanders can take deliberate actions to either engage or oppose supplier actions based on political market performance.

The primary contribution of this research is to begin to examine the implications of performance dynamics within political markets. Adding the construct of political market performance to the political markets framework reveals that variations in political market performance can be associated with specific types of corporate political activity.

This paper aims to investigate effect of infill density, fabricated built orientation and dose of gamma radiation to mechanical tensile and compressive properties of polylactic acid (PLA) part fabricated by fused deposit modelling (FDM) technique for medical applications.

PLA specimens for tensile and compressive tests were fabricated using FDM machine. The specimens geometry and test method were referred to ASTM D638 and ASTM D695, respectively. Three orientations under consideration were flat, edge and upright, whereas the infill density ranged from 0 to 100%. The gamma radiation dose used to expose to specimens was 25 kGy. The collected data included stress and strain, which was used to find mechanical properties, i.e. yield strength, ultimate tensile strength (UTS), fracture strength, elongation at yield, elongation at UTS and elongation at break. The t-test was used to access the difference in mechanical properties.

Compressive mechanical properties is greater than tensile mechanical properties. Increasing number of layer parallel to loading direction and infill density, it enhances the material property. Upright presents the lowest mechanical property in tensile test, but greatest in compressive test. Upright orientation should not be used for part subjecting to tensile load. FDM is more proper for part subjecting to compressive load. FDM part requires undergoing gamma ray for sterilisation, the infill density no less than 70 and 60% should be selected for part subjecting to tensile and compressive load, respectively.

This study investigated all mechanical properties in both tension and compression as well as exposure to gamma radiation. The results can be applied in selection of FDM parameters for medical device manufacturing.

The aim of this study is to describe an improved experimental substrate for the mechanical testing of patient-specific implants fabricated using direct metal additive manufacturing processes. This method reduces variability and sample size requirements and addresses the importance of geometry at the bone/implant interface.

Short-fiber glass/resin materials for cortical bone and polyurethane foam materials for cancellous bone were evaluated using standard tensile coupons. A method for fabricating bone analogs with patient-specific geometries using rapid tooling is presented. Bone analogs of a canine radius were fabricated and compared to cadaveric specimens in several biomechanical tests as validation.

The analog materials exhibit a tensile modulus that falls within the range of expected values for cortical and cancellous bone. The tensile properties of the cortical bone analog vary with fiber loading. The canine radius models exhibited similar mechanical properties to the cadaveric specimens with a reduced variability.

Additional replications involving different bone geometries, types of bone and/or implants are required for a full validation. Further, the materials used here are only intended to mimic the mechanical properties of bone on a macro scale within a relatively narrow range. These analog models have not been shown to address the complex microscopic or viscoelastic behavior of bone in the present study.

Scientific data on the formulation and fabrication of bone analogs are absent from the literature. The literature also lacks an experimental platform that matches patient-specific implant/bone geometries at the bone implant interface.

Presents both description and overview of the emerging field of biomechanical grippers and shows the prototype of biomechanical gripper called the Presov biomechanical robot gripper. Biomechanical robots and biomechanical grippers belong under biorobotics and bioengineering systems. Basic components of biorobotics include biomechanisms, biocontrol, biointelligence and biosensors. The Presov Biomechanical Robot Gripper is an electrically‐driven, multi‐fingered dextrous gripper, which has many features that conventional industrial robot grippers do not have. This gripper has been developed in the Department of Industrial Robotics of the Technical University in Presov, Slovak Republic.

Wall climbing robots' volume is needed to be very small in fields that workspace is limited, such as anti‐terror scouting, industry pipe network inspecting and so on. The purpose of this paper is to design a miniature wall climbing robot with biomechanical suction cups actuated by shape memory alloy (SMA) actuators.

Based on characteristics of biologic suction apparatuses, the biomechanical suction cup is designed first. Theory analysis of the suction cup is made considering elastic plate's deflection and SMAs constitutive model. A triangular close linkage locomotion mechanism is chosen for the miniature robot because of its simple structure and control. The robot's gait, kinematics, and control system are all illustrated in this paper.

Experiments indicate that the suction cup can be used as an adhesion mechanism for miniature wall climbing robots, and the miniature robot prototype with biomechanical suction cups can move in straight line and turn with a fixed angle on an inclined glass wall.

This paper describes how a miniature wall climbing robot with biomechanical suction cups actuated by SMA without any air pump is designed.

This paper describes SHAPE TAPE™, a thin array of fiber optic curvature sensors laminated on a ribbon substrate, arranged to sense bend and twist. The resulting signals are used to build a three dimensional computer model containing six degree of freedom position and orientation information for any location along the ribbon. The tape can be used to derive dynamic or static shape information from objects to which it is attached or scanned over. This is particularly useful where attachment is only partial, since shape tape “knows where it is” relative to a starting location. Measurements can be performed where cameras cannot see, without the use of magnetic fields. Applications include simulation, film animation, computer aided design, robotics, biomechanics, and crash testing.