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This paper reports on the development of a simple manufacturing process for polymeric multilayer substrates utilising the thermoplasticity of thermoplastic resin. Features and defects noted in manufacturing trials of the substrates are also reported. The process involves a polymer‐based thick film conductive paste screen printed on a hole‐punched thermoplastic resin film and dried. The films are stacked to form multiple layers and are then compressed into one unit. As the extremely thin thermoplastic resin film layers are equivalent to a single layer, a feature of this substrate is its exceptional thinness. As thermoplastic resin is used as a base material, the soldering process and other connecting technologies which may be used in place of solder connection are also examined.

As announced in the May issue of Hybrid Circuits, ISHM‐Benelux is organising a one‐day conference on applications of hybrid circuit technology.

The fifth in the series of Printed Circuit World Conventions is being held in Glasgow, Scotland, from 12—15 June 1990. It is organised by the UK Printed Circuit World Convention Committee under the direction of the co‐sponsors: EIPC (Europe), IMF (UK), IPC (USA), JPCA (Japan) and PCIF (UK).

This paper reveals a new methodology for predicting the most efficient design rules to follow for high density printed wiring boards prior to physical layout. The only input is from a schematic diagram, parts list and proposed board size. The methodology attempts to a priori determine the wiring capabilities of different PWB designs for a given product application. The particular focus is the difference between through‐hole and HDI designs.

Printed Circuit World Convention 5, which took place at the Forum Hotel and Scottish Exhibition & Conference Centre, Glasgow, from 12–15 June 1990, will be reported in two parts. Part 1, in this issue, covers an introduction to the event, the Opening Ceremony and a number of the technical sessions. The remaining technical sessions will be reported in Part 2 in the following issue.

This study aims to present a mathematical method based on Poisson’s equation to calculate the voltage and volume charge density formed in the substrate under the floating gate area of a multiple-input floating-gate metal-oxide semiconductor metal-oxide semiconductor (MOS) transistor.

Based on this method, the authors calculate electric fields and electric potentials from the charges generated when voltages are applied to the control gates (CG). This technique allows us to consider cases when the floating gate has any trapped charge generated during the manufacturing process. Moreover, the authors introduce a mathematical function to describe the potential behavior through the substrate. From the resultant electric field, the authors compute the volume charge density at different depths.

The authors generate some three-dimensional graphics to show the volume charge density behavior, which allows us to predict regions in which the volume charge density tends to increase. This will be determined by the voltages on terminals, which reveal the relationship between CG and volume charge density and will allow us to analyze some superior-order phenomena.

The procedure presented here and based on coordinates has not been reported before, and it is an aid to generate a model of the device and to build simulation tools in an analog design environment.

In the context of fixed-wing aircraft wing assembly, there is a need for a rapid and precise measurement technique to determine the center distance between two double-hole components. This paper aims to propose an optical-based spatial point distance measurement technique using the spatial triangulation method. The purpose of this paper is to design a specialized measurement system, specifically a spherically mounted retroreflector nest (SMR nest), equipped with two laser displacement sensors and a rotary encoder as the core to achieve accurate distance measurements between the double holes.

To develop an efficient and accurate measurement system, the paper uses a combination of laser displacement sensors and a rotary encoder within the SMR nest. The system is designed, implemented and tested to meet the requirements of precise distance measurement. Software and hardware components have been developed and integrated for validation.

The optical-based distance measurement system achieves high precision at 0.04 mm and repeatability at 0.02 mm within a range of 412.084 mm to 1,590.591 mm. These results validate its suitability for efficient assembly processes, eliminating repetitive errors in aircraft wing assembly.

This paper proposes an optical-based spatial point distance measurement technique, as well as a unique design of a SMR nest and the introduction of two novel calibration techniques, all of which are validated by the developed software and hardware platform.

This paper aims to provide an insight into recent advancements and developments of robotics for Natural Orifice Transluminal Surgery (NOTES) procedures.

Following an introduction that highlights the evolution from Minimally Invasive Surgery (MIS) to NOTES in the medical field, this paper reviews the main robotics systems that have been designed and implemented for MIS and NOTES, summarising their advantages and limitations and remarking the technological challenges and the requirements that still should be addressed and fulfilled.

The state-of-the-art presented in this paper shows that the majority of the platforms created for NOTES are laboratory prototypes, and their performances are still far from being optimal. New solutions are required to solve the problems confronted by the proposed systems such as the limited number of DOFs, the limited resolution, the optimal fixation and stiffening of the instruments for enabling stable and precise operation, the effective transmission of forces to the tip tools, the improvement of the force feedback feeling and the proper visualization and spatial orientation of the surgical field. Advances in robotics can contribute significantly to the development and future implementation of the NOTES procedure.

This paper highlights the current trends and challenges ahead in robotics applied to NOTES procedure.