Design optimization for a kinematic coupling for use in vacuum with minimum particle generation

In the semiconductor industry, integrated circuits with nanometre scale structures are manufactured on silicon wafers. Particle contamination on the topside of the wafer can result in the defectivity of the entire die. In the ever-increasing efforts to create smaller structures onto a wafer particle contamination becomes more restrictive to...

Air-based contactless wafer precision positioning system: Contactless sensing using charge coupled devices

This paper presents the development of a contactless sensing system and the dynamic evaluation of an air-bearing based precision wafer positioning system. The contactless positioning stage is a response to the trend seen in the high-tech industry, where the substrates are becoming thinner and larger to reduce the cost and increase the yield....

High Accuracy Terrestrial Positioning Based on Time Delay and Carrier Phase Using Wideband Radio Signals

Accurate position solutions are in high demand for many emerging applications. Global navigation satellite systems (GNSS), however, may not meet the required positioning performance, especially in urban environments, due to multipath and weak received power of the GNSS signal that can be easily blocked by surrounding objects. To achieve a high...

Air-Based Contactless Wafer Precision Positioning System

This paper presents the development of a contactless sensing system and the dynamic evaluation of an air-bearing-based precision wafer positioning system. The contactless positioning stage is a response to the trend seen in the high-tech industry, where the substrates are becoming thinner and larger to reduce the cost and increase the yield....

Design of Sparse Multiband Signal for Precise Positioning with Joint Low-Complexity Time Delay and Carrier Phase Estimation

This paper presents a methodology to design a sparse multiband ranging signal with a large virtual bandwidth, from which time delay and carrier phase are estimated by a low complexity multivariate maximum likelihood (ML) method. In the estimation model for a multipath channel, not all reflected paths are considered, and time delay and carrier...

Design considerations for ferrofluid pressure bearing pads

The novel contribution of this research is insight into the influence of different parameters in the magnet configurations on the load and stiffness of a ferrofluid pressure bearing. It is shown that magnets with a small cross-section magnetized alternatively up and downwards combine a high load capacity and moderate stiffness while being low...

Robust Low-cost Planar Positioning Stage: For Smartphone Microscope to Diagnose Malaria in Developing Countries

In 2018, there were more than 200 million reported cases of malaria worldwide, most of which were in Africa. Adequate diagnostics are required to properly treat the disease. According to the WHO, microscopic examination of a blood smear is the Gold Standard of malaria diagnosis. Currently, it is a labor-intensive process requiring trained...

3DOF(xyθ_z) measurement of a planar stage with one single 1D CCD from a 2D Moiré pattern

As technology is advancing, the need for precision stages is increasing. These stages are being used with (electron) microscopes for scientific research and industrial applications. They can be operated manually or by actuators, where the motorized stages are quite expensive in general and the cost increase significantly if better performance is...

Variable Fractional Order (VFO) PID Control for Precision Positioning: A Frequency Domain Approach

Stringent control demands from the high-tech mechatronics industry have warranted the need to explore potentially advantageous non-linear controllers. Variable Fractional Order (VFO) calculus provides one such avenue to build non-linear PID-like controllers. VFO calculus is the generalization of integer order differentiation and integration,...

The Optimal Sequence for Reset Controllers

The PID controller is one of the most used controllers in the industry. However, fundamental limitations due to linearity restrict its performances when higher bandwidth, stability, and precision are required simultaneously in today’s high-tech industry. Reset control is a promising nonlinear control strategy which can overcome these limitations...

Development of a low-cost computer vision sensor for precision positioning systems: Exploring the limits of computer vision sensors in precision systems

Computer vision has been on the rise over the last decades. The applications of computer vision are mostly found within the domain of robotics and Unmanned Aerial Vehicle's. The use of computer visions in precision industry is new and offers both opportunities and challenges. In high performance precision systems the demands on sensors is set...

Development of CRONE reset control

In high-tech industry (sub)nanometre precision motion control is essential. For example wafer scanners, used for production of integrated circuits, have to provide (sub)nanometre precision positioning whilst satisfying challenging requirements on speed at the same time. It is in demanding cases like this that different requirements begin to...

Impact Drive Mechanism with Nanometer Precision, actuated by a Pulse generating Voice-Coil Motor

From the results it can be concluded that a fixed and a free voice-coil actuated impact drive mechanism can be used as a positioning system in a precision environment, such as the semiconductor industry and extreme large telescopes, to position an object within 1 nanometer and hold the position passively stable within 10nm/hr. The empirically...