Compensating torque ripples in a coarse pointing mechanism for free-space optical communication: A Gaussian process repetitive control approach

Actuators that require commutation algorithms, such as the switched reluctance motor (SRM) considered in this paper and employed in the coarse pointing assembly (CPA) for free-space optical communication, often have torque-ripple disturbances that are periodic in the commutation-angle domain that deteriorate the positioning performance. The...

Cross-coupled iterative learning control: A computationally efficient approach applied to an industrial flatbed printer

Cross-coupled iterative learning control (ILC) can improve the contour tracking performance of manufacturing systems significantly. This paper aims to develop a framework for norm-optimal cross-coupled ILC that enables intuitive tuning of time- and iteration-varying weights of the exact contour error and its tangential counterpart. This leads...

Miniaturized engineered heart tissues from hiPSC-derived triple cell type co-cultures to study human cardiac function

Human heart tissues grown as three-dimensional spheroids and consisting of different cardiac cell types derived from pluripotent stem cells (hiPSCs) recapitulate aspects of human physiology better than standard two-dimensional models in vitro. They typically consist of less than 5000 cells and are used to measure contraction kinetics although...

Highly reproducible tissue positioning with tapered pillar design in engineered heart tissue platforms

We present a novel design of elastic micropillars for tissue self-assembly in engineered heart tissue (EHT) platforms. The innovative tapered profile confines reproducibly the tissue position along the main micropillar axis, increasing the accuracy of tissue contraction force measurement. Polydimethylsiloxane-based pillars were designed and...

Cascaded Calibration of Mechatronic Systems via Bayesian Inference

Sensors in high-precision mechatronic systems require accurate calibration, which is achieved using test beds that, in turn, require even more accurate calibration. The aim of this paper is to develop a cascaded calibration method for position sensors of mechatronic systems while taking into account the variance of the calibration model of...

Gaussian Processes for Advanced Motion Control

Machine learning techniques, including Gaussian processes (GPs), are expected to play a significant role in meeting speed, accuracy, and functionality requirements in future data-intensive mechatronic systems. This paper aims to reveal the potential of GPs for motion control applications. Successful applications of GPs for feedforward and...

Gaussian Processes for Advanced Motion Control

Machine learning techniques, including Gaussian processes (GPs), are expected to play a significant role in meeting speed, accuracy, and functionality requirements in future data-intensive mechatronic systems. This paper aims to reveal the potential of GPs for motion control applications. Successful applications of GPs for feedforward and...

Cross-Coupled Iterative Learning Control for Complex Systems: A Monotonically Convergent and Computationally Efficient Approach

Cross-coupled iterative learning control (ILC) can achieve high performance for manufacturing applications in which tracking a contour is essential for the quality of a product. The aim of this paper is to develop a framework for norm-optimal cross-coupled ILC that enables the use of exact contour errors that are calculated offline, and...

An engineered heart tissue platform with integrated pacing microelectrodes

A Miniaturized EHT Platform for Accurate Measurements of Tissue Contractile Properties

We present a wafer-scale fabricated, PDMS-based platform for culturing miniaturized engineered heart tissues (EHTs) which allows highly accurate measurements of the contractile properties of these tissues. The design of the platform is an anisometrically downscaled version of the Heart-Dyno system, consisting of two elastic micropillars inside...

Miniaturized engineered heart tissues from human induced pluripotent cell-derived co-culture

Miniaturized engineered heart tissues from HiPSC-derived co-culture

A miniaturized EHT platform for contractile tissue measurements

We presented the smallest and best characterised EHT devices to date. The devices were fabricated by wafer-scale silicon and polymer processing, characterised by nanoindentation and finite-element simulations, and transferred to 96-well plates for cell seeding and optical tracking of bundle contraction. Cell bundles remained functional for at...

Building blocks for a European Organ-on-Chip roadmap

This paper summarizes the outcome of the Organ-on-Chip (OoC) ORCHID Strategy workshop (Leiden, the Netherlands, 17 January 2019) intended to establish a European OoC roadmap through expert discussions, conclusions and recommendations. The workshop identified six specific building blocks for the OoC roadmap: (1) application, (2) specification, (3...

Cytostretch, an Organ-on-Chip Platform

Organ-on-Chips (OOCs) are micro-fabricated devices which are used to culture cells in order to mimic functional units of human organs. The devices are designed to simulate the physiological environment of tissues in vivo. Cells in some types of OOCs can be stimulated in situ by electrical and/or mechanical actuators. These actuations can mimic...

Fabrication and Characterization of an Upside-Down Carbon Nanotube Microelectrode Array

Microelectrode arrays (MEAs) are widely used in biological application to locally stimulate and record the electrical activity of living cells. Here, a novel fabrication process for a carbon nanotube (CNT)-based MEA integrated on the backside of a free standing stretchable membrane is reported. The new<br/>process flow overcomes the manually...