Circular Image

J.M.P. Geraedts

info

Please Note

17 records found

Doctoral thesis (2023) - Z. Liu, C.C. Wang, J.M.P. Geraedts, E.L. Doubrovski
Garments, one of the human basic needs, were customized and handmade before the Industrial Revolution. After the realization of mass production, the cost of a piece of clothing became lower, but some disadvantages arose. Garments were no longer made to measure and overproduction caused environmental problems. The new developments in digital garment design and digital customization target addressing these limitations.
The computational design of knitting attracted increased attention in recent years. In this dissertation, we consider the customized design and fabrication of 3D and 4D garments as knitwears. The 3D knitwear fits the target human body, and the 4D knitwear also considers comfort during body movement. The main research question (RQ) is: How to design customized 3D and 4D knitwear and generate instructions for a digital knitting machine?
In this dissertation, we researched computational knitwear design methods. We considered not only 3D fitting but also comfort during motion (4D). Our research can be applied in garment production (especially mass customization) or other knitting applications. Garment designers and other industrial designers can use the proposed methods to generate knitting instructions for free-form 3D surfaces. Our 4D design method helps designers place elastic or other varied knitting structures while keeping the intended 3D shape. This dissertation presents new perspectives on computational approaches to existing manufacturing techniques. It also provides enough details to further develop such design systems to be applied in practice. ...

Method based on Geometric Computing and Machine Learning

Doctoral thesis (2022) - G. Fang, C.C. Wang, J.M.P. Geraedts
Soft robots that are built from materials with mechanical properties similar to those of living tissues can achieve tasks like never before in comparison to conventional rigid robots. Powered by the compliance of soft materials and novel structure designs, complex motion (e.g., bending, twisting, and extension) can be accomplished in robotic bodies. We now see soft robots being used to grasp fragile objects and detect confined areas. However, conventional modeling and control approaches, which rely on the rigidity of the robot body, are less effective when directly applied to soft robotic systems. Therefore, new methods and algorithms need to be developed that allow modeling and kinematics control for soft robots.

In model-based robot control, kinematics comprise the fundamental knowledge that can be used to build the mathematical connection between control parameters and robot status. Unlike rigid robots, whose kinematics are well studied and have fast (analytical) solutions, effective and general kinematics computing methods for soft robot systems are still lacking. According to the modeling perspective (i.e., forward kinematics (FK)), predicting the whole-body shape of soft robots under actuation is a non-trivial task since the non-linear deformation in robot bodies and the hyperplastic properties of soft materials create challenges in balancing accuracy and computational costs in existing FK models. The lack of modeling tools further brings the difficulties in developing advanced algorithms to inverse kinematics (IK) and (statics) control thereafter. This Ph.D. project aims to develop a general soft robot kinematics computing pipeline, that can contribute to the effective control of soft robot systems to accomplish given tasks.

A fast numerical simulator for soft robots is firstly presented in this thesis, in which the shape of the robot body is discretely represented by volumetric elements. The development of this simulator was inspired by the fact that the hard-to-model actuation input (e.g., cable force, pressure, and electronic field) in soft robot systems can be directly modeled or transformed to fit the shape change in actuation elements. An optimization pipeline was built to minimize elastic energy in the body elements and compute the deformed shape with actuation parameters as input. As a general numerical simulator, it supports the modeling of various types of actuation, and the hyperelastic soft material properties are integrated. A fast collision checking and response model was added to predict the behavior of soft robots under robot-robot collisions and robot-environment interactions. The numerical computing process of our simulator shows good convergence, even for soft robots with large (rotational) deformation in their bodies, and can therefore balance the computational cost and model precision. In comparison to commercial \textit{finite element analysis} (FEA) software, this geometry-based simulator demonstrates a 20-fold faster computing speed, and the simulation result can well fit the shape that was captured from the physical setup.

The IK problem of soft robots is defined as computing proper actuation parameters that drive soft robots to accomplish given tasks. In this thesis, task-specific IK objectives (which are mainly geometrically defined) are formulated, and the optimal actuation parameters are detected using gradient-based iteration. Through the developed simulator, the gradients of objective functions are estimated using numerical differences. The sequence of motion can be successfully computed using this IK solver, and its efficiency has been verified in two case studies, which include path-following and object pick-and-place.

For the final stage of this Ph.D. project, the speed and precision of the IK solver are enhanced through machine learning. Fully connected neural networks are invited to fit functions of FK and the Jacobian of IK-related objectives. With the high efficiency in the forward propagation of networks (in analytical form), the gradient-based IK solver can run in real-time. Sim-to-real transfer learning is applied to eliminate the reality gap and make the computed actuation parameters more precise in physical setups. Applying sim-to-real transfer learning can also benefit the efficiency of the data generation process. In our pipeline, massive training data is first generated in a virtual environment using a fast simulator; thereafter, a lightweight network layer is employed to map the result of the simulation to the physical hardware. As a result, the amount of physical data can be reduced by 60% to train a network that accurately computes IK solutions.

In conclusion, this dissertation presents a pipeline that computes kinematics solutions for soft robots. A fast geometry-based simulator is presented to contribute to building an iteration-based numerical IK solver. Machine learning is applied to accelerate IK computing to real-time speed with enhanced precision. Task-specific kinematics control is realized in different soft robot systems to verify the effectiveness of the proposed method. The algorithms and code presented in this Ph.D. thesis are open-sourced for researchers and designers, and have the potential to become a general tool for designing and controlling soft robots. Future studies on the design optimization and high-level control of soft robots can all benefit from the research outcomes of this project. ...

The mass-production of one-of-a-kind products

The project is divided into three sub-assignments: - A future manufacturing context must be envisioned and the most important requirements synthesized. - An implementation of this envisioned manufacturing system must be developed and validated. - An exemplary-product producible by this system must be designed, showcasing the benefits of the envisioned manufacturing method. Envision Following the problem definition and assignment defined in the Introduction phase, the current state of manufacturing and how we got there is analyzed. A future context around a complete product-life-cycle is envisioned. Within this vision both the product as well as the factory are explored. The design tasks were performed in parallel, but they will be described in sequence. First the factory will be discussed: a manufacturing concept is synthesized, the underlying principles are analyzed, and a factory classification is done. Then the exemplary-product will be discussed: the underlying principles of product personalization are explored, and the principles of a product within the developed future context are described. The acquired knowledge gets integrated in a design brief and a list of directing requirements. These form together with the future vision, a starting point to design an actual realization of both product and factory in the phase after the Envision phase. Actualization Following the design brief defined in the Envision phase, the conceptualization of both product and production need to go hand in hand. A realizable future production system must be accompanied by a product that showcases this manufacturing method and the other way around: the personalizable product-family requires a production system that is capable of producing these one-off-products at a high production-capacity. Both design tasks were performed in parallel, but they will be described in sequence in this part of the report. First the exemplary-product will be discussed: the choice, the conceptualization, and the embodiment. Then the Transcended production system will be discussed: the required standardization, the proposed production cluster, conceptualization of the production framework and embodiment of the initial prototype. This prototype can then be used for validation of the propped framework in the phase after the Actualization phase. Validation In the Actualization phase a framework is proposed for the full, so called, pick-and-place on-printing process. This framework should be able to produce the designed computer mouse. And a prototype is developed solving the most important FDM-Cabinet embodiment challenges, resulting in a working system. The goals for this prototype are, firstly to demonstrate an initial framework that is able to produce a personalized consumer electronics product from start to finish at a mass-production output capacity (theoretically). And secondly to validate the pick-and-place on-printing process as a feasible method to produce multi-component parts. The Core Functional Requirements for this prototype are discussed and validated in each of following sub-chapters. The last subchapter validates the Core Functional Requirements for the exemplary-product itself. The research findings will then be used for evaluation in the phase after the Validation phase. ...

Design of a gripper for automated sorting of mixed aluminium scrap to create added value

Master thesis (2019) - Alex Klootwijk, Jo Geraedts, Zoltan Rusak, Tijmen Oudshoorn
Reukema is the biggest non-ferrous trader in the Netherlands. They want to investigate the possibility of sorting aluminium in a robotic system. Aluminium is one of the most used materials worldwide. Demands for aluminium are ever increasing. Recycling scrap is needed to keep up with the demand. An important step in the recycling process is the separation into different alloys, as sorting aluminium creates added value. Currently, the only way to sort the scrap is to have it done manually in low-wage countries such as China, Pakistan or India. This thesis describes the analysis of the problems which may occur implementing such a system. Three idea directions were generated based on the analysis executed. It was found that using a robotic arm with a robotic gripper would unwantedly increase the complexity of the sorting system. Simply pushing the scrap off a conveyor belt was found to be the best design. Based on this finding three different concepts were created, of which one, the concept in which material is fed into the system in a line, was selected. A pusher, perpendicular to the conveyor belt, pushes the material off the belt. Material is classified using a camera and a line scanner. The scrap is stored in a bunker under the sorting installation. In the last phase of this project the gripper was detailed. It was important to maximize the quality of sorting. Besides this, the reliability of the complete system needed to be maximized, while the cost per tonne should be minimized. The final design is a gripper which gives the pieces of scrap a parabolic trajectory before they land in the bunker for storing. The gripper is constructed out of steel and is 250 by 125 [mm]. A rib of 100 [mm] was added to lift pieces of scrap off the conveyor belt and decrease friction. ...
Master thesis (2019) - Guusje Harteveld, Joris Dik, Jo Geraedts
A novel combination of analytical techniques for measuring optical properties of glaze and paint as input for computer modelling is used to investigate the influence of the green glaze layer present on top of the black underpainting in the background of Girl with a Pearl Earring. The absorption spectra of paint layers from paint reconstructions and samples of the original painting were determined using micro spectrophotometry. Additionally, Bidirectional Reflectance Distribution Function (BRDF) measurements were done on paint reconstructions to determine the reflection distribution from multiple illumination and observation angles. Already existing height and layer thickness information was compiled in a digital 3D model of the painting which, in combination with the optical properties, was used as a base for rendering using the Mitsuba render engine. The experimental results clearly show that the green glaze layer under specific angles darkens the appearance of the black paint onto which it is applied. The computer simulation shows promising results for digitally recreating the painting. ...

Extend the capabilities of fused deposition modelling to industry 4.0 standard

The fourth Industrial Revolution stands for the current trends of automation and data exchange in manufacturing technologies - which comes with a considerable amount of opportunities as most manufacturers attempt to stay ahead of the competition. One of the possibilities is the addition of FDM printing - one of the types of additive manufacturing, also called 3D printing. Currently, FDM printing techniques are not fully industrialized. There is a significant need for human labor. Therefore, there was a need for a solution - on how to integrate FDM printing techniques in a production line by applying the core design principles of industry 4.0. The final design includes and modular systems with high interconnectivity allowing cyber-physical systems to interact through the smart factory. This project consists of a chapter with an analysis including a company analysis and competitors analysis, the section about FDM printing and industry 4.0 and trend analysis. The ideation phase includes brainstorm sessions, CF session, and decision-making phase. From these ideas, two concepts were developed. In the chapter conceptualization, these two Concepts were tested with three products suitable for 3D printing. Two workflows were made to test these concepts. The most beneficial concept is concluded in physical prototypes - which supports the four pillars of industry 4. The chapter embodiment includes the design with its features including; positioning, continuous printing, automatic refill, temperature control, movement control, quality check and a fitting digital system. Parts of the design were tested with a focus on temperature control, movement control, and positioning. Physical models were built to test positioning and movement control. These steps were evaluated and design drivers from these tests were added to the final design. ...

Scanning and printing a painting's appearance

The appearance of a painting cannot solely be described by the depiction that it presents to the viewer. When viewing the artifact in real life, we find that the painted surface is in effect a three-dimensional landscape of paint. Paintings, “moveable, largely two-dimensional images created for the primary purpose of providing a visual experience”,1 can be created using a vast variety of materials on a range of supports. They are commonly built up as a complex stratigraphy of layers, generally consisting of a support, ground layer(s), one or multiple layers of (semi-) transparent paints, and in many cases a protective varnish layer. The current appearance of a painting is determined by the way a painter used and applied the materials, but also effects of aging, conservation and restoration treatments, which all continue to influence the physical state of a painting. Historically, cultural heritage (CH) reproductions were hand-crafted, and created for instance to disseminate or replace artworks, or to train in the skill of their creation. Also modern reproductions — or facsimiles — are still large hand-crafted, and for instance serve to provide access to (fragile) artworks or even complete (CH) sites, or to recreate their original appearance. Alternatively, reconstructions might reside only in the virtual domain. The continued development of digital imaging and digital fabrication technology (i.e. 3D printing) provides new opportunities for appearance reproduction, also suitable for application in the CH domain. If we want to replicate material appearance, we need to understand how (the appearance of) material is perceived. A material is, however, not observed directly, but has to be lighted, and via the light that is scattered by the material humans can perceive it. Appearance is therefore the light-material-confounded proximal stimulus for the human visual system (HVS). Even though we see, recognize and interact with a vast number of materials every day, and can effortlessly distinguish between them, it turns out that the perceptual mechanisms that underlie this, are still quite poorly understood, including linking individual appearance attributes to measurable and fabrication parameters. One of the consequences of this is that an integrated approach to (total) appearance reproduction, including color, topography/ texture/shape, gloss and transparency/translucency, is still lacking. ...

Determining the location and range of motion of digital joints in 3D scans

Master thesis (2018) - Timo Johannes Dijkstra, Jo Geraedts, Jun Wu, Pieter van der Zwan
The versatility of the hands is revealed in its movements, but often not noticed before trauma occurs. Joint range of motion is used as a measure to follow the progress of diseases. A digital workflow for 3D data in medical appliances is envisioned for years.
The aim of this research is to develop a method that reliably and reproducability determine the range of motion of the digits. In current practice, the angles are measured using a goniometer. This method is very imprecise. Three methods to determine the location of joints in 3D hand scans can be distinguished: using heuristics, computer vision, and deep learning. Of those, deep learning is the most flexible, modern and accurate method and is therefore applied. The end result is a matrix containing the range of motion per joint and is applied to anatomically correctly manipulate a 3D model. For ease of manipulation, a physical manipulator is proposed. The results of this novel method show lower interrater differences than measurements with a goniometer. ...
Master thesis (2018) - Tim van den Ing, Jo Geraedts, Adrie Kooijman, Hugo van de Watering
The Rollz Motion is a mobility aid that can be transformed from a wheelchair to a rollator. Users of this Rollz Motion complain that it takes too much force to push the Rollz Motion as a wheelchair with a person inside. Especially users that live in hilly areas have these problems. This project tries to solve this problem through the creation of a power assisted push support system that can be attached to the Rollz Motion. This should lower the threshold of going for a walk and increase the range of environments that the users of the Rollz Motion can access.

Comfort -
As a first step the research focussed on how the users could benefit best from such a smart system. A force analysis validated the severity of the complaints and user interviews highlighted that users can develop a fear for mobility. The smart system should comfort the user by taking away this fear and it should comfort the push attendant by lowering the use force.

Support -
Some types of power assisted mobility aids have a high number of accidents. This shows that the user group is vulnerable. An analysis was done to test whether the Rollz Motion would be safe enough to motorise. Assistive supportive technology needs to be implemented in the design of the drive system to generate the necessary safety.

Perception -
Mobility aids suffer from product related stigma. This creates a threshold of going for a walk, makes users insecure and can have a negative effect on the mobility of the user. For new product development the stigma needs to be redesigned to make users proud and confident about using their product.

Prototype -
The first version of a push supportive system has been designed and prototyped. This system utilises a motor control algorithm that proved to be able to provide robust output in different contexts. It showed potential to lower the force of pushing a person in the Rollz Motion on a hill from 200N to 10N. ...

Applied to the craquelure pattern of paintings

Master thesis (2018) - Mathijs van Hengstum, Jo Geraedts, Joris Dik, Yuke Song, Dimitra Dodou, Tessa Essers

Melting and cooling plastics

Master thesis (2018) - Leander Hofman, Kaspar Jansen, Jo Geraedts
This thesis describes the process of redesigning the 3D-paintbrush. It looks into extruder screws for plastics and finds the best design variables for the 3D-paintbrush. Vortex cooling has been used to cool the extruded plastics fast and efficient. With the findings for melting and cooling the thesis looks at human-machine interaction and combines these findings into a final redesign. A mockup is made of the redesign to validate the interaction between the user and the 3D-paintbrush ...

How to bridge the gap between design methods and recycling practices

The topic of this thesis is design for recycling (DfR) of electronic products. More than ever before, electronic products are intruding into our everyday life, both in the household and in industry, resulting in increasing numbers of electronic products ending up in waste streams (also known as electronic waste, or e-waste). Electronic products contain a wide range of materials, such as iron, steel, lead, plastics, glass, aluminium, copper and precious metals. Materials are assembled using different types of connections, such as click or snap-fit joints, adhesive tape, screws, glue and soldering. Furthermore, different arrangements and positioning of materials, as well as the connections between them, lead to different kinds of product structures. These characteristics can make the recycling process for electronic products more or less difficult.

Design is seen as pivotal in the creation of products that can facilitate the recycling process. For this reason, in the past two decades there has been considerable research on DfR, resulting in a large number of methods and tools being developed. The aim of these methods is to assist designers in assessing the recyclability of their designs and to select adequate product design features that facilitate the recycling process. However, these methods do not seem to have been very effective; particularly not in the case of electronic products. This is because, despite the considerable number of methods developed thus far, and what they claim in theory, electronic products are still not being optimally disintegrated and separated in actual recycling processes. Consequently, the aim of this thesis is to uncover the various reasons for the mismatch between the theory and practice of DfR by undertaking a number of studies. ...
Master thesis (2017) - Michiel de Bie, Jo Geraedts, Nina Bogerd
This document covers the design process of a localized heating system suitable for retrofitting to buildings in the Netherlands ...

A journey of plastic

Master thesis (2017) - Jelle Algra, Jo Geraedts, Jouke Verlinden, Tiwánee van der Horst
This project is about controlling plastic such that a designer can create 3D art structures of 3 x 3 x 3 meters. The designer and main stakeholder (Tiwánee van der Horst) of this project has just started her own art business. Her inspiration to make art comes from her own graduation project. In this project she wants to convert 2D painting into 3D painting by swapping paint for plastic. She investigated painting and 3D printing techniques and combined them. The result is the idea to create a manually controllable extruder for plastic which translates her body movements into 3D art structures.

An extruder is a pipe (barrel) with a screw inside it and heating elements around it (figure 3). When the screw is rotated the threads (grooved ridges) will push the plastic forwards. The heating elements will melt the plastic along the way. The plastic will enter the extruder in a solid state and will leave the extruder in a molten state.

By manually controlling the extruder the designer can express her artistic creativity in 3D. The context for the artwork of Tiwánee van der Horst will be urban residential areas. In these areas she will integrate her artwork into existing features of buildings. The extruder will be used as a 3D paint brush in such a urban residential area.

The storyline throughout this report will be a journey of plastic. In the report it will be explained how plastic granulate (small pieces of plastic 4 x 4 x 4mm) is transformed and controlled by the 3D paint brush into plastic artworks.
...

Relieving the physical load on railway workers

Master thesis (2017) - Rutger Tollenaar, Jo Geraedts, Iemkje Ruiter, M Deerenberg
Working on the rail infrastructure is physically tough. Heavy tools are lifted and carried while in unfavourable postures and in a harsh environment. An integrated design of tool carrier and working process eliminates the toughest of the loads imposed on the body of railway workers. ...

Exploring Technology and Applications

Master thesis (2017) - Bart Peeters, Jo Geraedts, Jun Wu
The Curatio is a low-cost hand scanner which allows fast capture of accurate 3D hand scans, developed at the TU Delft in cooperation with Vectory3. Research done by several graduate students has produced reliable and accurate hand scans. Adding infrared thermographic imaging was deemed the next step forward in the scanner’s development.

Combining 3D hand scanning with medical thermography creates opportunities for product designers and medical professionals to better help people with hand conditions such as, among others, rheumatoid arthritis, diabetes and Raynaud’s syndrome.

This thesis explores potential applications and technology needed to combine both modalities, by presenting the development of a thermal camera module and its integration into the existing scanner workflow. Research conducted and results obtained show promise and provide a foundation for further research into this multi-modal system’s possibilities, limits and best suitable applications. ...

Supporting Designers in the Exploitation of Additive Manufacturing Affordances