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This paper aims to estimate the required insertion force and to analyze the influence of damping in a compliantly supported chamfered peg-in-hole assembly under dynamic conditions.

A mathematical model of the insertion process, including damping coefficient and stiffness of the compliance, insertion speed, mass, inertia and friction coefficient, has been developed. Computer aided design (CAD) model of the peg-in-hole assembly environment with passive compliance is created. The dynamic insertion force of the modeled environment is analyzed using multibody dynamics numerical solver.

The damping property of the viscoelastic materials used in the passive compliances suppresses the vibration caused due to the impulses in the transition of the peg in hole. It also increases the insertion force required for the peg insertion at the initial stage.

As the search strategies are not considered in this work, it is assumed that the initial contact is ensured between the chamfer and the peg of the assembly. A constant insertion speed is maintained throughout the insertion. Otherwise, it could have been varied at different stages of the insertion for reducing the assembly time.

The developed assembly model can be used for predicting the insertion forces of a chamfered peg-in-hole assembly and for designing/selecting the compliance device for the required assembly environment.

The proposed insertion model has considered the damping and elastic property of the compliance material as a parallel arrangement of spring and dashpot. This approach aids in modeling an insertion process closer to real-time assembly process.

The Author's company was the first in New Zealand to install automatic insertion equipment. The paper covers the appraisal of the following systems: manual insertion; semi‐automatic insertion; and automatic component insertion. The last of these comprises various types, namely bench type, pantograph machine, computer controlled (axial lead and general) and an in‐line assembly system. The computer controlled axial lead insertion equipment including design criteria is detailed at length, with some discussion of advantages.

The paper aims to investigate theoretically and experimentally the process of compliantly supported peg insertion into a bush for high‐speed assembly, when vibrations are provided to the bush in the axial direction, and to analyse the influence of the parameters of the dynamic system and excitation on the assembly process.

The mathematical model of parts vibratory insertion process is formed and the simulation is performed using a numerical computing software environment. The model includes inertia, compliance, dry friction, insertion speed and vibratory excitation. The three‐dimensional simulation of peg‐in‐hole insertion is accomplished using motion analysis software to test the influence of vibratory excitation on assembly failures, such as jamming and wedging. The experimental setup for the robotic vibratory assembly and the investigation methodology were presented. The experimental analysis of the vibratory insertion process of cylindrical parts with clearance is performed when the compliantly supported peg is inserted by the robot into the bush, which is excited in the axial direction.

The vibratory excitation allows preventing the balance between the insertion force and frictional forces and so to avoid jamming and wedging. It is advantageous to select such the frequency of vibrations under which the resonance state of the compliantly supported peg does not occur. The parameters of vibratory excitation and initial assembly state are defined which have the principal influence on the insertion duration and the success of the process. The experimental results show the applicability of the mathematical approach.

The assumption is made that the chamferless rigid peg moves in a plane in respect of the rigid bush with a chamfer. Also, it is considered that there is no impact during the peg and bush contact. The dynamic and static friction coefficient between the parts is equivalent and the insertion speed is constant.

The results can be useful aiming to design the reliable high‐performance vibratory assembly equipment for peg‐hole type parts, which does not require sensors, feedback systems and control algorithms.

The proposed method of applying the vibratory excitation during the peg‐in‐hole insertion process allows to avoid jamming and wedging, and to minimize the duration of the process.

The purpose of this paper is to develop a dual peg-in-hole insertion strategy. Dual peg-in-hole insertion is the most common task in manufacturing. Most of the previous work develop the insertion strategy in a two- or three-dimensional space, in which they suppose the initial yaw angle is zero and only concern the roll and pitch angles. However, in some case, the yaw angle could not be ignored due to the pose uncertainty of the peg on the gripper. Therefore, there is a need to design the insertion strategy in a higher-dimensional configuration space.

In this paper, the authors handle the insertion problem by converting it into several sub-problems based on the attractive region formed by the constraints. The existence of the attractive region in the high-dimensional configuration space is first discussed. Then, the construction of the high-dimensional attractive region with its sub-attractive region in the low-dimensional space is proposed. Therefore, the robotic insertion strategy can be designed in the subspace to eliminate some uncertainties between the dual pegs and dual holes.

Dual peg-in-hole insertion is realized without using of force sensors. The proposed strategy is also used to demonstrate the precision dual peg-in-hole insertion, where the clearance between the dual-peg and dual-hole is about 0.02 mm.

The sensor-less insertion strategy will not increase the cost of the assembly system and also can be used in the dual peg-in-hole insertion.

The theoretical and experimental analyses for dual peg-in-hole insertion are proposed without using of force sensor.

The purpose of this paper is to present a surgical robot for spinal fusion and its control framework that provides higher operation accuracy, greater flexibility of robot position control, and improved ergonomics.

A human‐guided robot for the spinal fusion surgery has been developed with a dexterous end‐effector that is capable of high‐speed drilling for cortical layer gimleting and tele‐operated insertion of screws into the vertebrae. The end‐effector is position‐controlled by a five degrees‐of‐freedom robot body that has a kinematically closed structure to withstand strong reaction force occurring in the surgery. The robot also allows the surgeon to control cooperatively the position and orientation of the end‐effector in order to provide maximum flexibility in exploiting his or her expertise. Also incorporated for improved safety is a “drill‐by‐wire” mechanism wherein a screw is tele‐drilled by the surgeon in a mechanically decoupled master/slave system. Finally, a torque‐rendering algorithm that adds synthetic open‐loop high‐frequency components on feedback torque increases the realism of tele‐drilling in the screw‐by‐wire mechanism.

Experimental results indicated that this assistive robot for spinal fusion performs drilling tasks within the static regulation errors less than 0.1 μm for position control and less than 0.05° for orientation control. The users of the tele‐drilling reported subjectively that they experienced torque feedback similar to that of direct screw insertion.

Although the robotic surgery system itself has been developed, integration with surgery planning and tracking systems is ongoing. Thus, the screw insertion accuracy of a whole surgery system with the assistive robot is to be investigated in the near future.

The paper arguably pioneers the dexterous end‐effector appropriately designed for spinal fusion, the cooperative robot position‐control algorithm, the screw‐by‐wire mechanism for indirect screw insertion, and the torque‐rendering algorithm for more realistic torque feedback. In particular, the system has the potential of circumventing the screw‐loosening problem, a common defect in the conventional surgeon‐operated or robot‐assisted spinal fusion surgery.

Small-bore drains (≤ 16 Fr) are used in many centers to manage all pleural effusions. The goal of this study was to determine the proportion of avoidable chest drains and associated complications when a strategy of routine chest drain insertion is in place.

We retrospectively reviewed consecutive pleural procedures performed in the Radiology Department of the McGill University Health Centre over one year (August 2015–July 2016). Drain insertion was the default drainage strategy. An interdisciplinary workgroup established criteria for drain insertion, namely: pneumothorax, pleural infection (confirmed/highly suspected), massive effusion (more than 2/3 of hemithorax with severe dyspnea /hypoxemia), effusions in ventilated patients and hemothorax. Drains inserted without any of these criteria were deemed potentially avoidable.

A total of 288 procedures performed in 205 patients were reviewed: 249 (86.5%) drain insertions and 39 (13.5%) thoracenteses. Out of 249 chest drains, 113 (45.4%) were placed in the absence of drain insertion criteria and were deemed potentially avoidable. Of those, 33.6% were inserted for malignant effusions (without subsequent pleurodesis) and 34.5% for transudative effusions (median drainage duration of 2 and 4 days, respectively). Major complications were seen in 21.5% of all procedures. Pneumothorax requiring intervention (2.1%), bleeding (0.7%) and organ puncture or drain misplacement (2%) only occurred with drain insertion. Narcotics were prescribed more frequently following drain insertion vs. thoracentesis (27.1% vs. 9.1%, p = 0.03).

Routine use of chest drains for pleural effusions leads to avoidable drain insertions in a large proportion of cases and causes unnecessary harms.

In the electronics industry of the Federal Republic of Germany 286,000 employees are working in assembly twice as many as in the automotive or machine building industries.

As a common transmission line, the microstrip line plays an important role in high-speed circuits. The purpose of this paper was to investigate the effects of the circuit design of microstrip lines on the signal integrity (SI). In addition, the influence of the type and thickness of the solder resist ink on SI was analyzed to provide guidance for the related producing process design of printed circuit boards (PCBs).

Microstrip line properties consisting of shape, line-width/line-space ratio, reference layer design and as-covered solder resist ink were designed to measure the insertion loss (S₂₁) in high-speed PCB.

The study showed that the insertion loss (S₂₁) of straight, meander, snake-shaped and wavy microstrip lines was approximately consistent. A microstrip line with width/space ratio less than 0.96 is necessary, as the differential line closing produces a mutual interference. Reference layer including the discontinuous area should be repaired by adjusting the microstrip line parameters. With regard to the solder resist ink, the insertion loss of novel solder resist ink decreased by 0.163 dB/in at 12.9 GHz and 0.164 dB/in at 14 GHz, compared with traditional solder resist ink. Accordingly, the insertion loss effectively improved at a lower thickness of solder resist.

This paper demonstrated that the common designing factors of line shape, line/space ratio, reference layer and solder resist influence microstrip line SI in the significant reference of designer-making PCB layout.

Examines the use of acoustic emission techniques for monitoring part mating during the assembly process. The frequency recorded during a peg insertion is compared with known frequencies of successful peg insertion by a microcomputer. This allows unsuccessful alignment to be readjusted which being monitored by a digital sound analyzer. Outlines the concept of part mating which is based on the peg‐in‐hole theory developed by Simunovic and describes an acoustic emission monitoring system. Concludes that acoustic monitoring provides a relatively low cost, low complexity system for part mating monitoring but may have limitation in manufacturing environments where there is excessive background noise or machine part vibration.

It is imperative to the successful automation of any product to establish and maintain satisfactory standards of component input.