This thesis presents a method for encoding viewing-angle-dependent images directly into the material of a 3D print. Custom-designed multi-material filament, combining transparent and opaque sections, is extruded through a rotating nozzle; controlling the rotation angle during extrusion determines where each section is placed along a printed line, so the image is written into the extrudate itself rather than added through separate lenses or a second process. Two optical effects are achieved this way: variable light transmission, where images emerge under backlighting, and a lenticular effect, where the naturally lens-shaped extrusion reveals different colours at different viewing angles. A purpose-built slicing application supports the full workflow, from filament design and optical preview to calibration and G-code generation. Single- and dual-image samples were evaluated qualitatively in flat and three-dimensional geometries. The intended colour placement carried through to the finished print and both effects were reproduced on flat walls, while three-dimensional geometries worked to a more limited degree. Print quality remains below high-fidelity output, limited by the dependence of resolution on line height and width and by an off-centre nozzle, filament twisting in the Bowden tube and insufficient cooling; the effect is also highly sensitive to lighting. The results establish material-encoded angle-dependent imaging as achievable on a modified single-nozzle extrusion setup, and identify the mechanical and workflow refinements needed to sharpen it. ... Read more

Dual-colour fused deposition modelling using a rotational nozzle can produce continuous colour gradients from a single dual-colour filament, but the colour deposited at any point is a direct function of the nozzle's rotational angle, so small orientation errors translate into visible, uncorrectable colour misregistration. This thesis investigates the extent to which computer vision and machine learning can detect filament colour orientation in real time and use it to drive closed-loop correction of nozzle rotation. A nozzle-mounted camera feeds a convolutional neural network that predicts orientation directly from the deposited filament's colour distribution; the estimate drives corrective G-code between toolpath segments. Under in-distribution conditions, the final model (Dataset v3) detected orientation accurately (mean absolute error 1.73°, 90th-percentile error 3.61°, 100% direction accuracy), but this did not transfer to unseen geometries (MAE 11.09°, P90 19.97°). Mechanistic analysis showed that the model infers orientation from nozzle-body reflectance and surrounding geometry, rather than solely from the colour boundary it was designed around. This behaviour propagated to closed-loop performance: large resolvable errors were corrected, confirming the control architecture is sound, but errors near the filament's resting state were imperceptible, and sustained non-equilibrium orientations drove the filament into states absent from training, causing the loop to act on confidently incorrect estimates. Closed-loop performance is therefore governed not by the control loop but by the reliability of perception under untrained conditions. ... Read more

Thin-walled products use surface geometry to combine function with low mass. Additive manufacturing can produce these shapes, but producing the shape is not equivalent to producing its intended load paths when the deposited material response is anisotropic.

We investigate whether multi-axis deposition can translate a shell load case into inspectable, finite-width, stress-aligned conformal toolpath proposals before fabrication.

Short-fibre fused-filament fabrication (FFF) provides the practical case for direction-dependent deposition. The prototype links a shell stress field, shell-following layer surfaces, a spectral direction field, and finite-width path realization. Coverage, overlap, and directional error describe different geometric properties and are reported individually.

We then conduct two fixed-stress evaluations: a path-dependent manufacturing-aware comparative index relating coverage shortfall, misalignment, and bead discontinuity to local demand, and a path-free comparison between one conformal material frame and prescribed planar frames. Integrating mechanics, surface geometry, path generation, and fixed-stress evaluation in one inspectable workflow is the central contribution.

Across five thin-walled shell geometries, all fifteen recorded path realizations fell below the adopted contextual reference values for coverage shortfall, overlap, and directional error at the trace-mesh resolution used in the study. A supplemental numerical check showed that exact path placement and derived measures remained sensitive to solver initialization at that resolution. For the two geometries used in the path-free material-frame comparison, the conformal frame gave a substantially lower index on the end dome, while the small wing difference was inconclusive.

These results support initial computational feasibility for generating and evaluating stress-aligned conformal paths. Physical calibration, machine planning, and coupled structural re-analysis are the next steps towards predictive and manufacturing use. ... Read more

Lattice structures are traditionally designed to be rigid, holding a single shape. Adaptive lattices move between shapes, letting one structure serve changing needs, such as those of a morphing wing rib. Existing actuated lattices follow transformations defined at design, and methods for placing actuators keep all other members at fixed length. None of them releases a member to change length freely, although mixing fixed, actuated and released members could bring a lattice to targets chosen after its design. This thesis pursues that possibility as an inverse design research, for planar pin-jointed lattices of given topology. Given a target curve, it asks which members to fix, actuate or release, how far each actuator must travel, and under what conditions the target can be reached. A computational framework searches the role assignments and computes the actuator travels that bring a set of target nodes onto the curve. Four structures were studied; in the three of these that carry redundant members, no assignment moved the target nodes without a release. These members bind the frame into groups whose lengths cannot change independently, so an actuator stays blocked until releases break every group it belongs to. Which members are released therefore decides whether such a lattice can adapt at all. Tolerance and design preferences, in contrast, change which assignment is selected, not whether one exists. On physical demonstrators built for two of the structures, four computed assignments, with three to seven actuators, ran without adjustment of the computed travels. Taken together, these results state four conditions for adaptation: the roles form a mechanism its actuators control; that motion moves the target nodes toward the curve; an exact fit needs at least one actuator per placement and spacing requirement; and the path avoids folds and stays within travel limits. The first and third can be checked before any search is run. Actuation can thus be computed rather than chosen by hand, a step toward lattices that reconfigure after deployment.
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Despite growing interest in multi-colour FDM printing, current methods remain limited by hardware complexity, material waste, and the inability to produce smooth gradients. This research investigates a novel method for multi-colour printing using a single nozzle combined with dual-colour and triple-colour filament, with controlled rotation, to influence perceived colour blending and transitions.

A standard Ender 3 printer was modified to include a rotational B-axis, with hardware enhancements such as a slip ring and belt-driven stepper motor to reduce torsion and nozzle deviation. Custom G-code was generated via Grasshopper, linking image-based colour data to nozzle rotation angles, allowing for systematic testing of smooth gradient and snappy colour switch performance. Extensive testing was conducted on 2D and 3D samples to evaluate the effects of parameters such as rotation angle, step size, speed, and print direction on colour reliability and gradient quality.

The results demonstrate that nozzle rotation can produce smooth gradients and snappy colour switches without purging, with reliable reproduction of the base colours and limited success with intermediate colour filaments. Mechanical factors such as nozzle deviation and filament torsion still affect reliability, but calibration and passive settings can reduce these effects significantly. These findings position rotational nozzle systems as a promising third category in multi-colour FDM printing, combining expressive colour control with relatively simple hardware adaptations and low waste.
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This dissertation develops an optimization framework for multi-axis additive manufacturing, with a particular focus on wire arc additive manufacturing (WAAM). It introduces the novel space-time topology optimization approach that integrates structural design and fabrication sequence planning by defining material distribution across both spatial and temporal dimensions.
In this framework, a pseudo-density field defines the structural layout, while a pseudo-time field encode the fabrication sequence, offering detailed insights into the layer-by-layer manufacturing process. Two key advancements are developed in order to improve the manufacturability: First, a thermal regularization method is proposed to ensure a smooth and continuous pseudo-time field without local minima. Second, a layer geometry control scheme is implemented to improve the consistency of the layer dimensions.
The framework is further adopted to address challenges associated with residual stress and thermal-induced distortion in WAAM, employing the inherent strain method as a simplified process simulation model. In addition, the anisotropic nature of material properties in WAAM is considered, enabling the rational alignment of material deposition orientation to enhance performance.
Numerical results demonstrate the feasibility and effectiveness of the proposed optimization framework, inspiring the exploration of the innovative potential offered by multi-axis additive manufacturing. ... Read more

Negative linear compressibility (NLC) describes the relative increase or decrease in a material's linear dimension when subjected to an increase or decrease in external pressure, or a decrease or increase in internal pressure, respectively. This is a rare material property found in only a few naturally existing materials. These materials are not only limited by their availability but also by the range, strength, and stability of NLC behavior. This limitation can be addressed through the design of NLC metamaterials, which are engineered materials composed of repeating architectures or material layouts on the microscopic scale, known as base or unit cells. These cells define the macroscopic properties of the material. In this case, negative linear compressibility.

While there are different methods for designing NLC metamaterials, none of them involve the use of topology optimization (TO), which serves as a powerful tool for designing optimized metamaterial structures. Materials can be designed for different parameters such as base material and pressure applied, while also considering different constraints that may be application-specific.

This study aims to create isotropic NLC metamaterials by designing NLC metamaterial unit cells using a systematic design methodology. We achieve this goal using a density-based TO approach, incorporating different constraints and selecting appropriate parameters to obtain different metamaterial unit cells that exhibit NLC behavior in both two and three dimensions.

The resulting 2D designs exhibited an NLC value of -2.370 %/bar and -3.367 %/bar. While the 3D designs exhibited an NLC value of -2.212 %/bar and -3.534 %/bar. The obtained NLC value and the efficacy of the design method are validated through numerical analysis and experimental testing, with the experimental design showing a maximum deviation of 26.099% from the NLC value obtained through TO. Finally, comparative and parameter studies helped better elucidate the advantages, limitations, and areas for improvement of the methodology used to obtain these designs. ... Read more

Wire arc additive manufacturing (WAAM) is attributed to higher material deposition rates and medium to large build volumes. Integration of multi-axis (more than three) material deposition kinematics in WAAM can bring a paradigm shift in the metal additive manufacturing industry. The material build-up mechanism employing directed energy deposition results in localized melting and solidification of feeding wire making the fabricated structure inherently prone to deposition defects such as dimensional distortion, residual stresses, solidification cracking, and porosity. Optimization of welding process parameters can improve cracking and porosity behavior. However, the problem of distortion is inevitable, and current mitigation strategies rely on post-processing or symmetric material deposition; while the former decreases the effectiveness of WAAM and increases costs, the latter could only be implemented for specific parts. Tackling this problem with the help of computational design tools is a recent approach, and Fabrication Sequence Optimization dictating material deposition is numerically predicted to limit the extent of the distortion effectively compared to conventional planar horizontal deposition; however, this still lacks experimental validation. This research presents a series of fabrication experiments using Al5356 Aluminum-magnesium alloy wire in a 6-axis robotic WAAM setup in two parts: (1) Process parameters identification for optimal bead characteristics for Al5356 wire, (2) Fabrication of single-bead multi-layered thin-walled shell structures using planar and optimized material deposition. A digital image correlation-based non-contact in-situ distortion measurement setup is constructed to analyze strain development during fabrication process and 3D scanning of fabricated structures is performed to estimate dimensional deviation. The experimental findings revealed an improvement in geometrical formation and a qualitative indication of distortion minimization with an optimized fabrication sequence. ... Read more

Performance-driven generative design has been commonly used in engineering applications. In addition to performance metrics, aesthetics play an important role in the acceptance of generatively designed forms. When generating these shapes using generative programs, it is not clear in advance what the outcome will be, and thereby what they will look like. However, the appearance of these shapes can currently almost always be described as quite novel and organic. This affects the acceptance of these shapes and the number of iterations or post-processing needed to end up with a shape that is aesthetically acceptable.

This graduation project aims at exploring, identifying and validating aspects of 3D generated designs that contribute to a more aesthetic appearance in order to increase aesthetic acceptance and move towards intentional aesthetics in 3D generative design.

A review of existing literature was done on the history of aesthetics, aesthetics in product design and aesthetics in generative design. This resulted in useful insights in aesthetic principles. These existing principles were then reviewed in relation to 3D generative designed forms. Through that analysis, hypotheses were synthesised on how the aesthetic appeal of these shapes could be increased.

A first user study was conducted to test these hypotheses and to gain valuable insights into what aspects of a 3D form are important for aesthetic appreciation. For this study, many 3D generated designs were created across different product groups. The products were placed in a virtual environment in order for the participants to view them in true 3D through a virtual reality headset. Via an open discussion with the participants during the viewing of the different designs, valuable insights were gathered on aspects that positively or negatively contributes to the aesthetic appreciation of these forms.

These insights resulted in guidelines to increase aesthetic appreciation for 3D generated designs. A second, quantitative user study was then set up to validate the desired effect of the new guidelines. Twenty new designs were created and selected to be put in pairs containing designs that did and did not display features from the new guidelines. Through an online survey, these pairs were judged by 90 respondents on the desired effects, resulting in an extensive data set. Data analysis was conducted, and Pearson correlations showed a positive effect between the effects from the guidelines and the aesthetic appreciation of the generated forms.

These guidelines can therefore be used as actionable recommendations for designers, engineers and architects seeking to optimize both the structural and aesthetic qualities of generatively designed product. ... Read more

Additive Manufacturing (AM) plays a crucial role in the revolution towards Industry 4.0, by enabling the direct translation of digital 3D models into physical objects while reducing process steps and minimizing human intervention. While conventional AM machines are generally limited to three-axis movement, multi-axis AM equipment extends the manufacturing flexibility by enabling the fabrication of freeform layers, thus creating new opportunities to improve part quality, though at the cost of increased complexity in process planning. Wire Arc Additive Manufacturing (WAAM) is a multi-axis technique for producing large metal components, with potential applications in maritime, aerospace and civil infrastructure. However, this potential is hindered by factors such as deformation during fabrication, which compromises part precision and can lead to process failure. Recently, a computational approach has been developed to reduce distortion by optimizing the fabrication sequence. While promising, the optimized sequence is characterized by large variations in layer thickness, rendering them non-manufacturable. This research proposes numerical methods to evaluate and restrict layer thickness in fabrication sequence optimization, ensuring uniform thickness within each layer and a consistent average thickness across the entire sequence. A 3D computational framework has been developed, integrating latest advancements in sequence optimization. To address the intensive computation in 3D, this framework features a parallel implementation using the PETSc library. This framework enables the numerical assessment of the method’s performance and provides a foundation for future experimental validation. ... Read more

Background: Despite over a century’s worth of technical improvements, the longterm survivability associated with orthopedic implants continues to fall short. In contrast to earlier designs, implant failure is no longer caused by structural failure of the implant itself. Rather, it results from the implant’s long-term detrimental effects on the surrounding bone tissue. Over time, changes in mechanical loading conditions induce a reduction in bone density, increasing the risk of fracture, and destabilizing the bone-implant interface. The mechanisms which drive peri-prosthetic bone loss are complicated and inter-related. Add to this the unique morphological variations among patients, and an optimal one-size-fits-all solution seems unlikely.....
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The use of multi-axis additive manufacturing has enabled the possiblity to fabricate parts using curved layer deposition. Compared to the traditional deposition using planar layers of a fixed thickness, multiaxis additive manufacturing significantly increases the number of possible fabrication sequences. With the introduction of a time component for topology optimization in recent work, fabrication-processdependent physics can now be incorporated in the optimization process. The fabrication sequence resulting from such complex optimizations can lead to layers with large variations in thickness. For manufacturability reasons, considering multi-axis additive manufacturing, this variation should be controlled. In this thesis, we present a method to control the variation in thickness of the projected layers to improve the manufacturability. We use the continuous pseudo-time field and its gradients to track the development of the layer boundaries. To demonstrate the effectiveness of the method, we apply the thickness control method on a fabrication sequence optimization for minimizing thermal distortion. The results show that the proposed method is able to reduce the variation of thicknesses compared to the original sequence optimization without thickness control resulting in improved manufacuturability. ... Read more

In the realm of traditional additive manufacturing, design and fabrication sequence planning have historically followed separate tracks. However, recent strides in the field, particularly in the utilization of robotic arms with multiple degrees of freedom, have brought forth a revolutionary approach known as Space-Time Topology Optimization (STTO). This groundbreaking algorithm breaks down the barriers between design and fabrication by simultaneously optimizing the structure and fabrication sequence. It achieves this feat by employing density and time fields as design variables, allowing for a holistic and integrated approach to the manufacturing process.
However, within the framework of STTO, multiple iterations of finite element computations become necessary. This results in a substantial computational burden throughout the overall process.
My contribution within STTO lies in its adoption of a multi-resolution strategy. This strategy enables the use of different resolutions for the design fields, enhancing computational efficiency. Coarsening, a critical component of this strategy, is implemented through a sophisticated weighted average scheme. This coarsening process facilitates the construction of stiffness matrices with significantly reduced finite element calculations, resulting in substantial time savings during the optimization process.
The impact of coarsening in STTO has been rigorously studied across various levels, yielding remarkable results and advantages. In 2D scenarios, this approach has achieved an impressive 5-fold reduction in computation time, while in the more complex 3D domain, it has led to an astounding 30-fold decrease. Moreover, it's worth noting that compliance, a crucial performance metric, maintains its integrity even with coarsening, with compliance drop remaining below 5% for levels deemed acceptable. This study illuminates the profound implications of coarsening within the STTO framework, emphasizing the significant strides made in computational efficiency while ensuring structural integrity and performance. ... Read more

We explain the design and analysis of a novel voxel design with the goal of reducing assembly time and complexity of the robot-material system. Recent advances in robot-material systems, on the other hand, have focused on mechanical properties, design, and production methods. Making it possible to create cellular structures in harsh and remote environments. These systems, which are built up of voxels and small mobile robots that live on top of the structure and move the cellular structures, nevertheless lack a connecting mechanism that reduces total system complexity and assembly time to a level that is desirable to people.

The design of these voxels prioritizes ease of assembly through simple actuation and is investigated by proposing a method to connect voxels via an end effector without removing mechanical qualities while maintaining the system’s modularity principle. Modularity is a design idea that divides a structure into smaller sections called voxels that can be built and assembled separately to build the required structure. Simultaneously, the end effector’s design aims to connect a voxel with the fewest degrees of freedom possible, while also holding a voxel throughout transit and placing the voxel in the desired spot.

A new connection mechanism for cuboctahedral cellular structures was devised, which would enable the building of required large-scale structures faster and easier. Several prototypes and experiments were used in the design of this connection mechanism. The final prototype was built by fused deposition modeling and demonstrated by attaching the end effector to a Universal Robot 5 (UR5) and completing a series of movements to simulate the autonomous assembly of a bridge. The concept evaluation resulted in an end effector that can connect all sides of the voxel with only two movements, without requiring the robot to go around the voxel. This idea lays the groundwork for enhancing the way robots form cellular structures and creating a mechanism to make them more appealing to humans when exploring remote settings. The study finishes with future research opportunities and prospective applications of such a connection mechanism in robot-material systems. ... Read more

The principles of repair and maintenance, reuse, and repurposing of products in a circular economy aim at further minimizing the environmental impact during the use of products before being processed for recycling. However, studies on lattice structures in various fields focus on mechanical characteristics, design, and manufacturing methods. Lattice structures are known for being lightweight, shock resistant, etc., but repair and maintenance of these lattice structures are rarely investigated. In this study, the repairability of lattice structures is explored to extend product lifespan by enabling multiple Repair & Reuse loops before the recycling loop in a circular economy. The principle of modularity was tested on lattice structures and its impact on the ease of repair, and manufacturing of large-scale lattice structures was analyzed. Modularity is a design principle of subdividing the structure into smaller parts called modules which can be independently created and assembled to form the desired structure. A hierarchical modular approach was introduced for cuboctahedral lattice structures that proposes assembling desired large-scale structures by using modules that are themselves assembled as a result of interconnecting sub-modules. The design of these unique sub-modules, intraconnection to form modules, and interconnections within these modules involved various prototypes and simulated iterations. The final prototype was fabricated using fused deposition modeling and tested under a quasi-static compression test to validate that there is no/negligible negative impact of modularity on the lattice structure’s mechanical strength. The hierarchical modular approach and its benefits for ease of repair and manufacturing were demonstrated over a fabricated and assembled scaled-down model of an arch-type pedestrian bridge. The product journey of structures built using this approach is illustrated with a focus on ease of manufacturing and the repair & reuse loops. The study concludes with possibilities for future explorations in regards to this study and potential applications of such hierarchical modular lattice structures. ... Read more

During this project the possibilities of enriching the functionality of an Ankle Foot Orthosis (AFO) by implementing mechanical metamaterials are researched. The project is executed for Buchrnhornen, a company based in Eindhoven which has over 70 years of experience in manufacturing orthopaedic shoes and orthosis in a traditional way. Mechanical metamaterials are artificial structures with mechanical properties defined by their structure rather than their composition. They consist of rationally designed unit cells with unique mechanical properties. The project focusses on replacing the hinges and stops used in a traditional AFO to block plantar or dorsal flexion by a mechanical metamaterial structure which could achieve the same mechanical functioning. A digital program in Grasshopper (Rhino plug-in) is developed which generates a design space based on an input scan of the patients lower leg. The design space is split up in different parts based on the mechanical requirements of the specific areas in the AFO. For each design space, a suitable topology infill which meets the mechanical requirement of the area is developed and generated. Through an input which can be defined per generated model, mechanical requirements can be customized per patient. The output of the digital program is a ready to 3D print .stl file. An extensive research on 3D print methods and materials is done in order to find the most suitable method to fabricate the generated model. The best option was found in a Composite Fibre Co-extrusion (CFC) printer which is able to implement carbon fibre in a model. The addition of carbon fibre ensures much stronger prints which are able to resist the high forces which are applied on the AFO. The project is finished with a conceptual model generated through the developed digital program as well as an extensive evaluation and advice on the researched print methods and topologies. To conclude the research, a list of generic findings and recommendations for further development within Buchrnhornen is provided. ... Read more

Repair and maintenance of products require few resources in a circular economy, minimising the environmental impact of manufacturing and use of products. Although lightweight lattice structures have been widely investigated in various fields owing to their advantages in terms of their mechanical characteristics and the development of additive manufacturing, research on lattice structures has focused mainly on process and design methods for structural development, and not on the repair of lattice structures. In the present study, the repairability of lattice structures was studied to extend the lifetimes of lattice-structured products; this would enable the reuse of products and induce people to directly get involved in creating a circular economy. To determine the factors to be considered for repairing lattice structures, standard specimens fabricated in the form of single undivided and adhesively bonded joint samples were fabricated by fused deposition modeling and compared under four quasi-static tests: compression, tensile, shear, and three-point bending. The octet-truss unit cell was used in the specimen with a strut diameter of 1–2.5 mm at 0.5 mm intervals and a length of 10 mm. The difference in mechanical response between the two groups was significant in the tensile and three-point bending tests, while the compressive and shear tests showed similar results. Therefore, determination of the direction of the stress imposed on the products is essential for the proper repair of the underlying lattice structures, prolonging the life cycle of the product and thus leading to a positive effect on the circular economy. ... Read more

Interwoven is a textile grown from plant roots, showing the intelligence of plants. It is originally from the attempt of training plant roots to form a manmade pattern since 2015 by visual artist Diana Scherer based in Amsterdam. Due to fragility, it still remains an artistic work. However, Interwoven has a great potential for sustainable product design if further development is made through altering the material structure.

Collaborating with Materials Experience Lab of Industrial Design Engineering in TU Delft, Diana Scherer wants to bring an artistic material closer to people’s daily life. The author, by following the Material Driven Design method (Karana et al., 2015)*, develop the material by altering material structure through hacking the growing process, incorporating generative design techniques and the results from the user studies, with a particular emphasis on people’s experience on interpretive level. Digital Fabrication techniques are used to design the structural pattern for achieving functionally graded material properties (e.g. spatially graded stiffness), and shape optimisation.

Based on Diana Scherer’s experience and early experiments, a few techniques are synthesized and developed in the tinkering with Interwoven. Some potential structures for digital biofabrication are: [1] root growth can be manipulated to mirror digitally generated patterns, which would provide intended technical and experiential characteristics in Interwoven; [2] roots grown in agar gel change properties to stiffer and stronger by hand feeling (further mechanical tests are needed); [3] roots can sew through descrete obstacles in their growing direction and these obstacles can be designed with digital fabrication techniques.

Combining the insights and experiential studies, a material concept has been created: showing roots glue-ability to porous materials and growing traces to blend nature and man-made world. The material experience vision is to exhibit the glue-ability of Interwoven through a daily object co-created by roots and digital manufactured structures and bring forward the collision and collaboration between natural growth and man-made world. The final product concept is to imitate one of the most mass-produced daily products - IKEA ALSEDA, questioning the current way of manufacturing and material use. The co-creation structure increased durability of Interwoven. ... Read more

The learning curve of novice surgeons takes about 25 surgeries to be proficient at the knee replacement procedure. So it is not just enough if we design efficient and more ergonomic surgical tools, it is also important to provide a learning platform for them to get better before they operate on a real patient. Although many training simulators are available to train different surgical procedures, most of them are digital trainers that simulate the surgical process in a virtual world. There are physical training simulators available in the market for surgeries like laparoscopy and arthroscopy, but not for arthroplasty. FOXPAT is a reusable training simulator for knee arthroplasty surgery. Unlike the existing digital simulators, FOXPAT is a physical simulation of a patient knee with integrated sensors. The training tool lets novice surgeons use actual instruments that are used in the operating theatre. Besides providing a realistic experience of the surgical procedure, the sensors track the usage of tools provide feedback to the surgeons on their outcome.
Arthroplasty being an invasive surgical procedure, any training model will be destroyed in every training session. This makes it difficult for any manufacturer to provide a reusable design that the novice surgeons can train multiples of times. Foxpat can promise such a long term reusability. Novice surgeons can practice the whole surgical procedure of knee replacement before they try on an actual patient. This includes letting surgeons performing actual cutting, drilling and milling procedures. By just replacing a set of low-cost polyurethane bones after every practice session, Foxpat will be ready for a next practice session. As the product is used for training the novice surgeons, these sessions take place either in a conference hall or in a hospital. A training support team or a local technician in the hospital helps to set up the device.
During this project, two iterations of working prototypes were developed and tested before reaching the final design. This design is now ready to be manufactured in small quantities of 50 pieces per year and requires another iteration for large-scale production.
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We present a novel DC motor driven soft robotic fish and optimization based on experimental, numerical and theoretical investigation into oscillating propulsion for primarily speed and secondarily efficiency. Our system outperforms the previously fastest soft robotic fish Zhong et al. 2017 by a significant margin of 27%, with speeds up to 0.85m/s. A simple wire-driven active body and soft compliant body were used to mimic highly efficient thunniform swimming. The efficient DC motor to drive the system decreases internal losses compared to other soft robotic oscillating propulsion systems which are driven by one or multiple servo motors. The DC motor driven design allows for swimming at higher frequencies. The current design has been tested up to 5.5 Hz but can potentially reach much higher frequencies. ... Read more