H. Van Brussel

KU Leuven | ku leuven · Department of Mechanical Engineering

The introduction of CIM (Computer Integrated Manufacturing) systems in the 1980s, aiming at integrating automatic workstations into fully automated factories, was not successful. The root causes of this failure were that the subsystems to be integrated were not suitably designed for easy integration into a larger system. This situation stimulated t...

This chapter establishes a context of our design for the unexpected (D4U). The various levels of system complexity are defined, and the superiority of structural design over functional design for D4U is highlighted.

This chapter discusses case studies and projects applying and investigating design for the unexpected. They focus on the design and development of holonic execution systems in a wide variety of manufacturing and nonmanufacturing applications. This variety of cases shows the universal applicability of the product-resource-order-staff architecture (P...

This chapter discusses work on multiagent (manufacturing) execution systems by others. It is not our intention at all to provide coverage or completeness for the research domain. Moreover, the inclusion or omission of contributions by other research teams does not reflect their importance or impact. The sole goal of our selection is to deepen the r...

This chapter presents the earlier results in our development of a holonic manufacturing systems framework, with a clear emphasis on manufacturing and logistics. The insights discussed in the previous chapters were used as precious guidelines and as a check for soundness when comparing options. In particular, design for the unexpected (low and late...

In software engineering, a reference architecture is defined as a set of coherent engineering and design principles used in a specific domain. It aims at structuring the design of a specific system architecture by defining a unified terminology, the structure of the system, responsibilities of system components, by providing standard templates, com...

This chapter presents a theoretical analysis/model of how designers elaborate systems that can handle unpredictable user requirements and integration requirements. No advanced know-how is required to understand this analysis; elementary set theory suffices (Cf. http://en.wikipedia.org/wiki/Set_theory – basic concepts and notation.). The analysis pr...

This chapter discusses four scientific laws or principles that apply to the artificial (i.e., to manmade systems). When bounded rationality determines what is possible or impossible, these principles are unavoidable and simply cannot be ignored by developers without consequences (i.e., failure, poor performance, or high costs). These laws concern f...

This chapter presents a sample application of the generic design principles discussed further in this book. The purpose is to communicate in a widely accessible manner what the contribution of design for the unexpected (D4U) can become when addressing a real-world challenge. In particular, the discussion wants to illustrate how a D4U contribution i...

This book presents in-depth insights on the design of ICT systems and infrastructures coping with requirements and demands that are unknown at design time. It is generically applicable to execution systems managing activities on resources, illustrated on manufacturing control, logistics, fleet robotics, intelligent traffic ... Originally, the resea...

Self-organizing software systems are an increasingly attractive approach to highly distributed, decentralized, dynamic applications. In some domains (such as the Internet), the interaction of originally independent systems yields a self-organizing system de facto , and engineers must take these characteristics into account to manage them. This revi...

Adhesive wear and thermal degradation are the main aging mechanisms of paper-based friction materials. However, how these aging mechanisms affect the tribological characteristics of such materials is not fully understood. In this paper, the respective influences of the two aging mechanisms on the tribological characteristics of the friction materia...

Retinal surgery is one of the most challenging types of surgery because of the scale and the fragility of the human eye anatomy. The surgeon suffers from limited positioning accuracy, tremor and poor force feedback directly affecting the quality of the surgical procedures. To tackle these issues, we developed a teleoperation system to assist surgeo...

A dynamic three-degree-of-freedom actuator/transducer element comprising at least three piezoceramic actuators and force sensors, as integrated stacks, which are preloaded in the housing by a low-stiffness tension bar, and are constrained, by means of a flexible shell, against shear force and torsion moment, whereby the element, when powered by ext...

The well-known tradeoff between transparency and stability challenges the realization of bilateral teleoperation systems. Ideal conditions for the four-channel framework have been presented, but the practical feasibility is hardly quantified. This brief bridges the gap between existing detailed analysis of basic two-channel controllers and the idea...

Retinal Vein Occlusion (RVO) is a common retinal vascular disorder which may cause severe loss of vision. Retinal cannulation appears to be the most effective treatment, but given the small diameter of a retinal vein, it is too difficult and risky for a surgeon to perform this procedure manually. This work reports on the development of an innovativ...

In this paper, a friction model appropriate for wet friction clutches based on the extension of the Generalized Maxwell Slip (GMS) friction model is integrated to a four-DOF lumped-mass-spring-damper system which represents a typical SAE#2 test setup. Degradation models expressing the evolutions of the friction model parameters are also proposed, w...

The demand for accurate and reliable positioning in industrial applications, especially in robotics and high-precusion machines, has led to the increased use of harmonic drives. The unique performance features of harmonic drives, such as high reduction ratio and high torque capacity in a compact geometry, justify their widespread application. Howev...

When applying machine learning technology to real-world applications, such as visual quality inspection, several practical issues need to be taken care of. One problem is posed by the reality that usually there are multiple human operators doing the inspection, who will inevitably contradict each other for some of the products to be inspected. In t...

Navigating an electrical wheelchair can be very challenging due to its large size and limited maneuverability. Additionally, target users often suffer from cognitive or physical disabilities, which interfere with safe navigation. Therefore, a robotic wheelchair that helps to drive can prove invaluable. Such a wheelchair shares the control with its...

This paper describes a force-measuring manipulator for minimally invasive surgery. It employs an extracorporeal force measurement system combined with a passive trocar support to deal with the restrictions of a single insertion point in the body. The first contribution is the detailed description of the design and the involved kinematics of the dev...

Task learning for behavior‐based mobile manipulation is formalized as a behavior recognition problem in this paper. The goal is to generate a behavior diagram through human demonstration, which can be used as a template for execution of a specified task. In order to extract significant and meaningful information from sensory data, various features...

Wet friction clutches play a critical role in vehicles equipped with automatic transmissions, power shift transmissions and limited slip differentials. An unexpected failure occurring in these components can therefore lead to an unexpected total breakdown of the vehicle. This undesirable situation can put human safety at risk, possibly cause long-t...

This paper discusses the effects of adhesive wear and thermal degradation on the dry frictional characteristics of paper-based friction materials against steel material. Some commercial paper-based friction materials typically used for clutch applications were subjected to adhesive wear and thermal degradation and the dry frictional characteristics...

The accuracy of machine learning systems is a widely studied research topic. Established techniques such as cross-validation predict the accuracy on unseen data of the classifier produced by applying a given learning method to a given training data set. However, they do not predict whether incurring the cost of obtaining more data and undergoing fu...

This paper presents a decision-making pattern that uses trust mechanisms. It comprises an expectation module that performs two functions. First, it infers—based on past performance—how information is to be understood (e.g. consider the expected outcome of a promise to deliver tomorrow, morgen, mañana or domani). Second, it infers—based on past perf...

An antagonistically actuated pair of pneumatic muscle actuators has recently become an interesting basic joint unit for developing humanoid robots or robotic manipulators in general. This basic unit exhibits some advantageous characteristics, such as high compliance, high power-weight ratio, and high volume-to-weight ratio. However, hysteresis and...

In this paper, we address some of the challenges that arise as model-mediated teleoperation is applied to systems with multiple degrees of freedom and multiple sensors. Specifically we use a system with position, force, and vision sensors to explore an environment geometry in two degrees of freedom. The inclusion of vision is proposed to alleviate...

Despite critical components, very little attention has been paid for wet friction clutches in the monitoring and prognostics research field. This paper presents and discusses an overall methodology for assessing the health (performance) and predicting the remaining useful life (RUL) of wet friction clutches. Three principle features extracted from...

By virtue of its outspoken multidisciplinarity, robotics is an extremely popular research field, but is not always exercised by researchers with the broad scientific view required to make breakthroughs. This leads to a very fragmentary research landscape. Robots have their roots in fiction (the Sorcerer’s Apprentice, Frankenstein, Golem, RUR). Thei...

The advantages of using piezoelectric actuators in ultra-precision applications are often impaired by nonlinear effects, in particular hysteresis, which may lead to positioning uncertainties of up to 15% of the actuator's stroke. Model-based compensation strategies are often prescribed in order to overcome this limitation and achieve better dynamic...

The design of a bilateral teleoperation system remains challenging in cases with high-impedance slave robots or substantial communication delays. Especially for these scenarios, model-mediated teleoperation offers a promising new approach. In this paper, we present a first stability discussion. We examine the continuous behavior using general contr...

This paper presents the development of a condition monitoring method for wet friction clutches which might be useful for automatic transmission applications. The method is developed based on quantifying the change of the relative rotational velocity signal measured between the input and output shaft of a clutch. Prior to quantifying the change, the...

Pattern recognition techniques have shown their usefulness for monitoring and diagnosing many industrial applications. The increasing production rates and the growing databases generated by these applications require learning techniques that can adapt their models incrementally, without revisiting previously used data. Ensembles of classifiers have...

For visual quality inspection systems to be applicable in industrial settings, it is mandatory that they are highly flexible, robust and accurate. In order to improve these characteristics a multilevel information fusion approach is presented. A first fusion step at the feature-level enables the system to learn from an undefined number of potential...

The Holonic Manufacturing Execution System (HMES), developed at K.U.Leuven, utilizes a service-oriented approach to control manufacturing operations in real time. This chapter first explains how manufacturing control emerges from interaction between intelligent products and intelligent resources. Services play a key role in this interaction and for...

The paper discusses manufacturing enterprises’ compelling challenges that are directly stemming from generic conflicts between competition and cooperation, local autonomy and global behavior, design and emergence, planning and reactivity, uncertainty and a plethora of information. Responses in product and service design, organization of production...

The European Project MABE has investigated the application of a holonic manufacturing execution system (HMES) to networked production. This HMES implements the PROSA reference architecture [1]. Intelligent products manage their production in cooperation with intelligent resources. These intelligent products generate swarms of lightweight smart obje...

The dream of holonic manufacturing is that fully operational Computer Integrated Manufacturing systems can be installed by merely plugging together manufacturing resources that are each controlled by an individual agent. The functionality of an holonic architecture would supersede and integrate the functionality currently in the islands of automati...

This paper discusses the application of the PROSA reference architecture [1] and its delegate multi-agent system coordination mechanism or D-MAS [2], [3] to robotic applications, particularly to the coordination of multiple mobile robots. Originally, PROSA and D-MAS have been developed for the manufacturing executions system or MES domain [4]. The...

This paper presents modeling, simulation and experimental validation of the friction material degradation effects on the dynamic engagement behavior of a wet friction clutch system. The clutch system is modeled as a 3 DOF lumped-mass-spring-damper incorporating an extension of the Generalized Maxwell Slip (GMS) friction model. The effects of the dy...

Dagstuhl seminar no. 10102 on discrete event logistic systems recognized a network of persistent models to be a “Grand Challenge.” Such on-line model network will offer an infrastructure that facilitates the management of logistic operations. This ambition to create a network of persistent models implies a radical shift for model design activities...

In robotics and in many other fields, time synchro-nization between a host computer and sensors or other comput-ers is essential for many reasons. Whereas past approaches have focused on phase and frequency estimation, little discussion seems to be available in literature on adopting uncertainty on these estimates to determine whether synchronizati...

With the objective of experimentally correlating several wear-process parameters, accurately and continuously over the duration of a sliding test, this paper presents a novel test rig as well as experimental results obtained by it. The developed test rig is a rotational one with axes supported on aerostatic bearings. It enables online measurement o...

This paper analyses and compares two passivity-based approaches that allow to include a-priori knowledge on the dynamic range of the human operator and/or the environment. This can lead to less conservative teleoperation systems compared to systems designed to be purely passive or absolutely stable. The first approach under investigation is a metho...

As the friction material degradation progresses, the normal contact stiffness of wet friction clutches, measured in the pre-sliding (stiction) regime that corresponds to the post-lockup phase, changes as revealed in our previous study. Consequently, change of the contact stiffness can affect the normal-mode dynamic behavior. If this hypothesis hold...

This paper presents the development of a condition monitoring method for wet friction clutches based on monitoring the change of the relative velocity signal measured between the input and output shaft of the clutch. To quantify the change of the signal, the engagement duration and two dissimilarity measures, namely the Euclidian and the Spectral A...

Theoretical modelling of wear is a valuable aid for designing and optimizing tribological systems, in particular those involving unlubricated contacts. However, most of the existing models are empirical in nature, which limits their applicability and predictive power. In this communication, a generic, asperity-level, theoretical model for predictin...

Tactile feedback is a major missing feature in minimally invasive procedures; it is an essential means of diagnosis and orientation during surgical procedures. Previous works have presented a remote palpation feedback system based on the coupling between a pressure sensor and a general haptic interface. Here a new approach is presented based on the...

Two main challenges in using a pneumatic artificial muscle (PAM) actuator are the nonlinearity of pneumatic system and the nonlinearity of the PAM dynamics. The latter is complicated to characterize. In this paper, a Maxwell-slip model used as a lumped-parametric quasi-static model is proposed to capture the force/length hysteresis of a PAM. The in...

Elastography is a useful and interesting technique that can be used to infer stiffness information from ultrasound medical images. In one decade of activity, the scientific community has developed this technique to a more and more mature stage, such that it has evolved into a fruitful application for clinical practice. During this decade, the evolu...

Bearings, friction wheels, cams, etc. are widely employed elements in machine construction. The modeling of the dynamics of rolling friction plays therefore a crucial role in the simulation and optimization of such systems. This paper describes a recently developed transient-rolling-friction model with its application to different generic dynamical...

The control of a supply chain becomes more and more complex. The actions and operations of the different parties need to be coordinated in order to control the supply chain in an efficient way. The concept of 'Intelligent Product' can play an important role in this challenge. The intelligent product searches actively for the needed services offered...

Many elderly and disabled people experience difficulties when maneuvering an electric wheelchair. Additionally, many users are not prescribed a standard electric wheelchair because they lack the necessary cognitive skills or their impairment prevents them from steering an electric wheelchair safely. In order to expand the potential group of electri...

Electric wheelchairs can provide necessary help to elderly or disabled people. If the people are unable to give precise and fine steering commands, an intelligent electric wheelchair can assist the driving by implementing a collision avoidance behaviour. However, a straightforward implementation of such an algorithm is not desired as the intent of...

Controlling a robotic device by using human brain signals is an interesting and challenging task. The device may be complicated to control and the nonstationary nature of the brain signals provides for a rather unstable input. With the use of intelligent processing algorithms adapted to the task at hand, however, the performance can be increased. T...

This paper discusses the integrated design of parallel manipulators, which exhibit varying dynamics. This characteristic affects the machine stability and performance. The design methodology consists of four main steps: (i) the system modeling using flexible multibody technique, (ii) the synthesis of reduced-order models suitable for control design...

Despite considerable research effort, the use of physics-based modelling to predict frictional behaviour is still a debatable question in modern tribological research. This article presents a dry-friction model, based on physical phenomena such as adhesion, elastic–plastic contact and deformation. This contribution offers a means to simulate all ki...

Elderly and disabled people can experience considerable difficulties when driving a powered wheelchair, especially if they do not possess the fine steering capacities that are required to perform certain manoeuvres, like avoiding obstacles or docking at tables. In order to help these people, several “intelligent” wheelchairs have been developed in...

In this paper, we present a framework for the classification of images in surface inspection tasks and address several key aspects of the processing chain from the original image to the final classification result. A major contribution of this paper is a quantitative assessment of how incorporating adaptivity into the feature calculation, the featu...

Bounded Environment Passivity, presented in this paper, allows one to de-sign teleoperation systems that behave passive provided that the environment with which interaction takes place, belongs to an a-priori defined range of environ-ments. The use of such a-priori knowledge on the environment reduces conser-vativeness with respect to classical des...

This paper describes a general method for task learning on behavior-based mobile manipulators. Primitive motions are defined as elementary behaviors in the system providing fast reactive interactions with the environment and the users. These behaviors are also used as basic units to construct the execution of a task. In this context, task learning...

This paper presents a mechatronic analysis of a teleopera- tion system that provides haptic feedback. The analysis, based on the Bounded Environment Passivity method, describes the combined eect of the teleoperation controller and the master and slave hardware, includ- ing the eect of structural flexibilities, which have often been neglected in the...

Aerostatic bearing solutions avoid problems related to friction and enable high precision linear guiding. However, their relatively low stiffness hinders the accuracy when disturbance forces, such as inertial effects or machining forces, are present. An active compensation strategy based on air gap shape control with piezoelectric actuators has bee...

This paper presents a novel design of face tracking algorithm and visual state estimation for a mobile robot face tracking interaction control system. The advantage of this design is that it can track a user's face under several external uncertainties and estimate the system state without the knowledge about target's 3D motion‐model information. Th...

Hysteresis is inherently present in Pneumatic Artificial Muscle (PAM) Actuators. Our new observation shows that the hysteresis in a PAM is characterized by quasirate independency and history dependency, and is completely described by the Maxwell-slip (MS) model. In this paper, we explain how to model the existing hysteresis in an antagonistic PAM c...

Wet friction clutches play a critical role in a transmission system. The clutches progressively degrade while the transmission is under operational condition. If the clutches unexpectedly fail, then the complete transmission will fail. To avoid unexpected failures, a proper condition monitoring tool extended with a lifetime prediction method must b...

Many simulation models are constructed to answer a specific question in a limited semantic domain (such as social interactions, gcospatial movement, or progress toward accomplishment of a task). This approach limits the reusability of individual models, and makes the construction of large, complex models inefficient. We describe a system approach t...

The main goal of this chapter is to demonstrate the potential benefits of controllers of the third concept, i.e. controllers with model-based haptic feedback, especially for telesurgical applications. Hereto, this chapter describes the practical implementation of the Stiffness Reflecting Controller. The experiments described in Section 5 support th...

The inherent hysteresis in a pneumatic artificial muscle (PAM) makes it difficult to control accurately the position of the PAM’s end effector. This hysteresis causes energy loss and the area of the hysteresis loop is dependent on the amplitude of the motion and on the underlying causes of the hysteresis phenomenon. This means that if the hysteresi...

Biological systems have proven a rich source of inspiration for engineered systems with highly desirable properties, such as distribution, decentralization, and dynamic adaptation. However, the inspiration has been selective. Certain features, such as interaction through a shared environment, are very widely imitated. Others are less frequently exp...

To process the large amounts of data industrial systems are producing nowadays, machine learning techniques have shown their usefulness in many applications. As the amounts of data being generated are getting huge, the need for machine learning methods which can deal with them in an appropriate way - i.e. methods which can be adapted incrementally...

A control scheme based on physiological parameters for the inflation of an intra-aortic clamping balloon is presented. Automatic volumetric pumps for the inflation of balloon catheter have been largely developed, although the process modelling for catheter mounted balloon’s inflation has never been discussed. Automatic inflation is a key issue for...

After clutch engagement in the post-lockup phase, the contact stiffness between friction materials and separators plays an important role in the dynamic behaviour of an Automatic Transmission (AT). The friction material deteriorates progressively during the service-life of a clutch, thus affecting the contact stiffness. The deterioration therefore...

The paper presents an experimental study of holonic schedule execution. The output from industry-strength scheduling software is used as an initial schedule to be executed by an HMES (Holonic Manufacturing Execution System) (Valckenaers, 2005). This Holonic Manufacturing Execution System compensates for possible simplifications in the schedule. The...

A supply network comprises a set of production entities. Each production entity is both specific and autonomous. Yet the production entities are collectively responsible for procurement, manufacturing and distribution activities associated with one or more families of related products.

Uncompensated friction forces compromise the positioning and tracking accuracy of motion systems. A unique tracking error known as quadrant glitch is the result of complex nonlinear friction behavior at motion reversal or near-zero velocity. Linear-feedback control strategies such as PID, cascade P/PI, or state-feedback control have to be extended...

To process the large amounts of data industrial systems are producing nowadays, machine learning techniques have shown their usefulness in many applications. As the amounts of data being generated are getting huge, the need for machine learning methods which can deal with them in an appropriate way -- i.e.\ methods which can be adapted incrementall...

This paper discusses the integrated design of mechatronic systems with varying dynamics, such as serial and parallel machine tools. This characteristic affects the machine stability and performance. A computer-aided integrated design methodology is proposed and validated on a pick-and-place robot. It consists of two main steps: (i) the derivation o...

This paper considers the optimal design of mechatronic systems with configuration-dependent dynamics. An optimal mechatronic design requires that, among the structural and control parameters, an optimal choice has to be made with respect to design specifications in the different domains. Two main challenges are treated in this paper: the non-convex...

The control of the flow of goods through an extensive chain conveyor system is a complex task. The currently used control system (based on dispatching rules) is robust but does not take advantage of all opportunities. An alternative approach makes use of a planning algorithm to determine the routing decisions. This requires however an ad hoc algori...

Due to the inherent hysteresis in a PAM, the accompanying control of such actuator becomes complicated. In this paper, the pressure/length hysteresis is mathematically described by applying a Maxwell-slip model. The model of this hysteresis is then fed forward to compensate for the actuator nonlinearities. The designed controller is therefore just...

For people with very severe motor dysfunctions, Brain-Computer Interfaces (BCIs) may provide the solution to regain mobility and manipulation capabilities. Unfortunately, BCIs are characterized by a limited bandwidth and uncertainty on the BCI output. In the past, we have developed a Bayesian plan recognition framework that estimates from uncertain...

When applying Machine Learning technology to real-world applications, such as visual quality inspection, several practical issues need to be taken care of. One problem is posed by the reality that usually there are multiple human operators doing the inspection, who will inevitable contradict each other occasionally. In this paper a framework is pro...

The Polyagent is a new modeling construct that represents each entity in the domain by a set of agents. A single persistent avatar maintains the system's overall model of the entity in question, and generates a stream of transient ghosts to explore various issues of interest to the agent. These ghosts may be applied in a variety of ways. We have us...

This paper presents a novel design of a robust visual tracking control system, which consists of a visual tracking controller and a visual state estimator. This system facilitates human–robot interaction of a unicycle-modeled mobile robot equipped with a tilt camera. Based on a novel dual-Jacobian visual interaction model, a robust visual tracking...

In a system using PAMs, a big research effort has been carried out to solve the control problem, in which the nonlinear dynamics of a PAM were left behind as a disturbance to that system. The inherent dynamics in a PAM is due to its constitutional materials which cause hysteresis during cyclic contraction/extension. Prior knowledge of the hysteresi...