Open-source Design Research Articles

Open-source workflow design and management software to interrogate duckweed growth conditions and stress responses

Duckweeds, a family of floating aquatic plants, are ideal model plants for laboratory experiments because they are small, easy to cultivate, and reproduce quickly. Duckweed cultivation, for the purposes of scientific research, requires that lineages are maintained as continuous populations of asexually propagating fronds, so research teams need to develop optimized cultivation conditions and coordinate maintenance tasks for duckweed stocks. Additionally, computational image analysis is proving to be a powerful duckweed research tool, but researchers lack software tools to assist with data collection and storage in a way that can feed into scripted data analysis. We set out to support these processes using a laboratory management software called Aquarium, an open-source application developed to manage laboratory inventory and plan experiments. We developed a suite of duckweed cultivation and experimentation operation types in Aquarium, which we then integrated with novel data analysis scripts. We then demonstrated the efficacy of our system with a series of image-based growth assays, and explored how our framework could be used to develop optimized cultivation protocols. We discuss the unexpected advantages and the limitations of this approach, suggesting areas for future software tool development. In its current state, our approach helps to bridge the gap between laboratory implementation and data analytical software for duckweed biologists and builds a foundation for future development of end-to-end computational tools in plant science.

An Open Source Design Optimization Toolbox Evaluated on a Soft Finger

An Open Source Design Optimization Toolbox Evaluated on a Soft Finger

Power tether for long duration multi-copter flight

The possibilities and promises of unmanned aerial vehicles (UAVs) for smart agriculture, 5G cellular integration, package delivery, and persistent surveillance are but a few of the active drivers for advancing UAV technology and systems. The UAVs' dependence on battery power represents a key limitation for practical deployment. As every remote pilot understands, even a modest research payload can limit a UAV's endurance to under 20 min. When horizontal maneuverability is not required, a power tether from the ground can provide near infinite flight time. Commercial tethers exist but can be prohibitively expensive or underpowered for research payloads. This paper describes the detailed design, construction, and operation of a relatively inexpensive open-source alternative. The designed and prototyped tether system delivers 1 kW of power at the tether base which, on an efficient UAV, corresponds to a payload of approximately 4.75 kg. We discuss the tradeoffs, design choices, best practices, and customization options, and provide empirical data for characterizing the power-payload relationship. The power and payload are scalable thanks to the modular design and the tools presented in this paper. The very low cost compared to commercial heavy-lift tether systems and the open-source design enable reproducibility and widespread use for supporting research, development, and emerging services/applications.

Efficient Arithmetic Block Identification With Graph Learning and Network-Flow

Arithmetic block identification in gate-level netlists plays an essential role for various purposes, including malicious logic detection, functional verification, or macro-block optimization. However, current methods usually suffer from either low performance or poor scalability. To address the issue, we come up with a novel framework based on graph learning and network flow analysis, that extracts desired logic components from a complete circuit netlist. We design a novel asynchronous bidirectional graph neural network (ABGNN) dedicated to representation learning on directed acyclic graphs. In addition, we develop a convex cost network-flow-based datapath extraction approach to match the predicted block inputs with predicted block outputs. Experimental results on open-source RISC-V CPU designs demonstrate that our proposed solution significantly outperforms several state-of-the-art arithmetic block identification flows.

RECO-ASCON: Reconfigurable ASCON hash functions for IoT applications

The need for reconfigurable lightweight cryptographic processors with low power consumption for securing the Internet of Things (IoT) with adaptive functionalities is getting attracted due to security properties, such as data fidelity, provenance, and privacy concerns. This paper presents RECO-ASCON, a reconfigurable security processor that supports both cryptographic Hash and Hasha ASCON algorithms. The proposed design is implemented in Chisel hardware construction language, an open-source hardware library. It has been evaluated in various hardware platforms such as FPGAs, embedded systems and ASICs with various technology nodes and design flows. In the PYNQ-Z1 board, RECO-ASCON can be mapped to five processors in total with a Micro-Blaze soft-core processor for streaming data to all of them while running at 200MHz without producing any timing violations. Moreover, mapping the proposed RECO-ASCON processor on the Nexsys4-DDR Xilinx Kit (ARTIX-7 chip) would cost ∼ two times fewer resources and run 1.25 × faster than the existing implementation of just one of the ASCON hash functions on the same family of the chip. We implement the proposed processor in 28 nm industry technology with commercial design flow, it achieves a maximum frequency of 1.12 GHz while achieving highest energy efficiency compared to the state-of-the-art implementations. The total area is only 9170.82um2 in 28 nm. To further evaluate the design, we also implement it with all open-source design tools and process technology libraries in 45 nm, it achieves 1 GHz maximum frequency and consumes only 18225um2 in 45 nm. Overall, the proposed reconfigurable processor is compact and more energy efficient, making it a perfect candidate to be deployed in wide range of IoT systems.

CAT on MOUSE: Control and automation of temperature for single-sided NMR instruments such as NMR-MOUSE.

Temperature-dependent experiments are a rapidly growing area of interest for low-field NMR. In this work, we present a new device for wide-range temperature control for single-sided NMR instruments. The presented device, called CAT, is simple to build, inexpensive, and easy to modify to accommodate different samples. We present the capabilities of the device using a freezing temperature study of acetic acid/water mixtures. Additionally, we present the stability of the device over long measurement times. We believe that by introducing such a device with an open-source design, we allow researchers to use it in a wide range of applications and to fully incorporate variable-temperature studies in the world of single-sided instruments.

3D printed rheometer drastically reduces instrument costs

An open-source design allows accurate rheometers to be made at home for a fraction of the cost of a traditional instrument.

Open-Source Designs for Distributed Manufacturing of Low-Cost Customized Walkers

To improve accessibility, this article describes a static, four-legged walker that can be constructed from materials and fasteners commonly available from hardware stores coupled by open-source 3D-printed joints. The designs are described in detail, shared under an open-source license, and fabricated with a low-cost open-source desktop 3D printer and hand tools. The resulting device is loaded to failure to determine the maximum load that the design can safely support in both vertical and horizontal failure modes. The experimental results showed that the average vertical failure load capacity was 3680 ± 694.3 N, equivalent to 375.3 ± 70.8 kg of applied weight with the fractured location at the wood dowel handlebars. The average horizontal load capacity was 315.6 ± 49.4 N, equivalent to 32.2 ± 5.1 kg. The maximum weight capacity of a user of 187.1 ± 29.3 kg was obtained, which indicates that the open-source walker design can withstand the weight requirements of all genders with a 95% confidence interval that includes a safety factor of 1.8 when considering the lowest deviation weight capacity. The design has a cost at the bottom of the range of commercial walkers and reduces the mass compared to a commercial walker by 0.5 kg (19% reduction). It can be concluded that this open-source walker design can aid accessibility in low-resource settings.

Deriving a year 2040 reference aircraft from a modern turboprop, implemented and calibrated in SUAVE

The FUTPRINT50 project is focused on designing and preparing ground for a hybrid-electric regional aircraft with a capacity of 50 passengers. The aircraft is designed for entry-into-service between 2035 and 2040. To evaluate and refine the design concepts, the project will use two different reference aircraft: one that is state-of-the-art, and another that is extrapolated to represent what a year 2040 model might look like. The ATR 42-500, a 50-seat aircraft with a design range of 840 nautical miles, will serve as the year 2000 reference aircraft. As part of the project, the open-source aircraft design tool SUAVE is adapted for use with hybrid-electric aircraft. The ATR 42-500 was reverse-engineered in the same SUAVE environment using official manufacturer data and other sources for reference and calibration. The environmental impact of the aircraft is assessed based on its emissions of CO2, NOX, and noise. The technology used in the ATR 42-500 will be outdated by 2040. To estimate the impact of the year 2035/2040 hybrid components, a year 2040 reference aircraft was implemented. This aircraft is based on the ATR 42-500 but will incorporate several further enhanced technologies, such as a higher wing aspect ratio, more efficient engines, and improved materials.

A Modular 3-Degrees-of-Freedom Force Sensor for Robot-Assisted Minimally Invasive Surgery Research.

Effective force modulation during tissue manipulation is important for ensuring safe, robot-assisted, minimally invasive surgery (RMIS). Strict requirements for in vivo applications have led to prior sensor designs that trade off ease of manufacture and integration against force measurement accuracy along the tool axis. Due to this trade-off, there are no commercial, off-the-shelf, 3-degrees-of-freedom (3DoF) force sensors for RMIS available to researchers. This makes it challenging to develop new approaches to indirect sensing and haptic feedback for bimanual telesurgical manipulation. We present a modular 3DoF force sensor that integrates easily with an existing RMIS tool. We achieve this by relaxing biocompatibility and sterilizability requirements and by using commercial load cells and common electromechanical fabrication techniques. The sensor has a range of ±5 N axially and ±3 N laterally with errors of below 0.15 N and maximum errors below 11% of the sensing range in all directions. During telemanipulation, a pair of jaw-mounted sensors achieved average errors below 0.15 N in all directions. It achieved an average grip force error of 0.156 N. The sensor is for bimanual haptic feedback and robotic force control in delicate tissue telemanipulation. As an open-source design, the sensors can be adapted to suit other non-RMIS robotic applications.

Development and Numerical Optimization of a System of Integrated Agents for Serial Production Lines

In modern high-volume industries, the serial production line (SPL) is of growing importance due to the inexorable increase in the complexity of manufacturing systems and the associated production costs. Optimal decisions regarding buffer size and the selection of components when designing and implementing an SPL can be difficult, often requiring complex analytical models, which can be difficult to conceive and construct. Here, we propose a model to evaluate and optimize the design of an SPL, integrating numerical simulation with artificial intelligence (AI). Numerous studies relating to the design of SPL systems have been published, but few have considered the simultaneous consideration of a number of decision variables. Indeed, the authors have been unable to locate in the published literature even one work that integrated the selection of components with the optimization of buffer sizes into a single framework. In this research, a System of Integrated Agents Numerical Optimization (SIGN) is developed by which the SPL design can be optimized. A SIGN consists of a components selection system and a decision support system. A SIGN aids the selection of machine tools, buffer sizes, and robots via the integration of AI and simulations. Using a purpose-developed interface, a user inputs the appropriate SPL parameters and settings, selects the decision-making and optimization techniques to use, and then displays output results. It will be implemented in open-source software to broaden the impact of the SIGN and extend its influence in industry and academia. It is expected that the results of this research project will significantly influence open-source manufacturing system design and, consequently, industrial and economic development.

3D Printer

Digital fabrication technology, also referred to as 3D printing or additive manufacturing, creates physical objects from a geometrical representation by successive addition of materials. 3D printing technology is a fast-emerging technology. Nowadays, 3D printing is widely used in the world. 3D printing technology has been increasingly used for the mass customization, production of any types of open-source designs in the field of agriculture, in healthcare, automotive industry, locomotive industry and aviation industries. 3D printing technology can print an object via layer-by-layer deposition of material directly from Computer Aided Design (CAD) model. This paper presents an overview of the types of 3D printing technologies, the application of 3D printing technology, and the materials used for 3D printing technology in the manufacturing industry.

Development of affordable 3D food printer with an exchangeable syringe-pump mechanism

The technique of additive manufacturing has increasing popularity in food research area as well as other scientific fields. However, 3D food printers are expensive options compared to 3D polymer printers. Scientists, that require laboratory scale production capacities, resemble the syringe-pump systems that available in open source and free hardware designs. Present study aimed to develop an exchangeable syringe-pump mechanism (SPM) to demonstrate transformation of conventional 3D printer from polymer to food extrusion. The SPM can print a variety of materials, including miscellaneous foods, pastes, hydrogels and even biopolymers. The complete mechanism relies mostly on 3D printed parts and costs approximately 72$. Therefore, it allows users to obtain a 3D food printer inexpensively and does not require large amounts of technical labor. The SPM uses big volume (60 ml) luer lock syringe and blunt tip needles for greater versatility and user-friendliness. It could also be extended with cooling mechanism, so that the proposed system gains unique attribute among its counterparts. Finally, a standard polymer-printing 3D-Printer was converted into a laboratory-scale food printer, and edible ink was successfully printed in the desired shape.

Designing and simulating realistic spatial frequency domain imaging systems using open-source 3D rendering software.

Spatial frequency domain imaging (SFDI) is a low-cost imaging technique that maps absorption and reduced scattering coefficients, offering improved contrast for important tissue structures such as tumours. Practical SFDI systems must cope with various imaging geometries including imaging planar samples ex vivo, imaging inside tubular lumen in vivo e.g. for endoscopy, and measuring tumours or polyps of varying morphology. There is a need for a design and simulation tool to accelerate design of new SFDI systems and simulate realistic performance under these scenarios. We present such a system implemented using open-source 3D design and ray-tracing software Blender that simulates media with realistic absorption and scattering in a wide range of geometries. By using Blender's Cycles ray-tracing engine, our system simulates effects such as varying lighting, refractive index changes, non-normal incidence, specular reflections and shadows, enabling realistic evaluation of new designs. We first demonstrate quantitative agreement between Monte-Carlo simulated absorption and reduced scattering coefficients with those simulated from our Blender system, achieving discrepancy in absorption coefficient and in reduced scattering coefficient. However, we then show that using an empirically derived look-up table the errors reduce to and respectively. Next, we simulate SFDI mapping of absorption, scattering and shape for simulated tumour spheroids, demonstrating enhanced contrast. Finally we demonstrate SFDI mapping inside a tubular lumen, which highlighted a important design insight: custom look-up tables must be generated for different longitudinal sections of the lumen. With this approach we achieved absorption error and scattering error. We anticipate our simulation system will aid in the design of novel SFDI systems for key biomedical applications.

Prototyping Visible Light Communication for the Internet of Things Using OpenVLC

Visible Light Communication (VLC) has emerged in the last few years as a promising technology not only for high-speed communication but also for serving a new generation of Internet of Things (IoT) devices that may leverage the pervasive lighting infrastructures. Integrating VLC in lighting environments for IoT requires the design of networked and intelligent luminaries and new IoT devices, encompassing the development of innovative technologies and new algorithms. A common experimental platform is necessary to lower the entrance barriers of VLC and speed up the research development. In this article, we provide guidelines for prototyping VLC for IoT applications, assisted by the open-source platform OpenVLC. We also introduce the new development on OpenVLC, which guarantees support for more powerful LEDs and much longer distance (extending the communication distance from 6 m to 19 m), dimming adaption, among other features. Its low-cost, open-source, and open-hardware designs allow researchers in the community to swiftly adapt it to suit their research purposes.

Geographical Dependence of Open Hardware Optimization: Case Study of Solar Photovoltaic Racking

Open-source technological development is well-known for rapid innovation and providing opportunities to reduce costs and thus increase accessibility for a wide range of products. This is done through distributed manufacturing, in which products are produced close to end users. There is anecdotal evidence that these opportunities are heavily geographically dependent, with some locations unable to acquire components to build open hardware at accessible prices because of trade restrictions, tariffs, taxes, or market availability. Supply chain disruptions during the COVID-19 pandemic exacerbated this and forced designers to pivot towards a la carte-style design frameworks for critical system components. To further develop this phenomenon, a case study of free and open-source solar photovoltaic (PV) racking systems is provided. Two similar open-source designs made from different materials are compared in terms of capital costs for their detailed bill of materials throughout ten locations in North, Central and South America. The differences in economic optimization showed that the costs of wood-based racks were superior in North America and in some South American countries, while metal was less costly in Central and South America. The results make it clear that open hardware designs would be best to allow for local optimization based on material availability in all designs.

Comprehensive Study of a FMaSynRM for forklift applications by FEM using open-source platform considering both electromagnetic design and modelling aspects

A comprehensive study of a ferrite magnet assisted synchronous reluctance machine (FMaSynRM) for the forklift applications by using open-source platform is introduced in detail in this paper including both modelling and electromagnetic design aspects. On the electromagnetism modelling side, this paper uses Elmer as the core and combines other open-source packages covering the preprocessing, solving, and postprocessing sections to build the finite element model of the FMaSynRM. On the electromagnetic design side of the FMaSynRM, this paper mainly discusses the single-double layer winding arrangement, rotor topology, and demagnetization performance. And the power, efficiency, and current maps of the finalized machine at different speeds and loads are estimated by the finite element method (FEM) using the open-source platform, which takes different control logics into consideration. Finally, the predicted results by FEM are verified by the tested results. The modelling method by using open-source platform and design procedure of the FMaSynRM presented in this paper can also be used in the design of other electrical machine types in the adjustable speed applications.

Open-Source Vertical Swinging Wood-Based Solar Photovoltaic Racking Systems

Vertical bifacial solar photovoltaic (PV) racking systems offer the opportunity for large-scale agrivoltaics to be employed at farms producing field crops with conventional farming equipment. Unfortunately, commercial proprietary vertical racks cost more than all types of conventional PV farm racking solutions. To overcome these cost barriers, this study reports on the development of a new wood-based PV racking design. The open-source design consists of a hinge mechanism, which reduces mechanical loading and enables wood to be used as the main structural material, and is the first of its kind. This open-source vertical wood-based PV rack is (i) constructed from locally accessible (domestic) renewable and sustainable materials, (ii) able to be made with hand tools by the average farmer on site, (iii) possesses a 25-year lifetime to match PV warranties, and (iv) is structurally sound, following Canadian building codes to weather high wind speeds and heavy snow loads. The results showed that the capital cost of the racking system is less expensive than the commercial equivalent and all of the previous wood-based rack designs, at a single unit retail cost of CAD 0.21. The racking LCOE is 77% of the cost of an equivalent commercial racking system using retail small-scale component costs, and is 22%, 34%, and 38% less expensive than commercial metal vertical racking, wood fixed tilt racking, and wood seasonal tilt racking costs, respectively. Overall, wooden vertical swinging PV racking provides users with a low-cost, highly available alternative to conventional metal vertical racking, along with a potential increase in energy yield in high wind areas thanks to its unique swinging mechanism.

Conceptual design modeling by the novel aircraft conceptual design and analysis system (ACDAS)

PurposeThroughout an aircraft development process, the conceptual design phase is an extremely important milestone; hence, the quality and success of this step directly affect the overall cost and lead time of the project. Because of this fact, the purpose of this study is to provide outputs and suggestions to the designing engineer regarding the requirements for reducing overall design time as well as costs and creating an ideal design at the early phases of the project by optimizing the aircraft development process.Design methodology approachThe system has been prepared parametrically and presents some performance specifications for the aircraft in the early phases of the design, for example, coefficients for lift CL as well as drag CD and weight as well as fuel estimations. The software uses a combination of well-known design techniques within just one platform in contrast to many other applications. Because of this feature, it is not needed to use different sub-platforms which would require an appropriate environment and even though would lead to complications with regard to the connectivity. The system also presents relevant information about the aircraft performance like velocity versus load factor (V-n) diagrams, maximum turn rate of climb, turn rate and climb angle graphs in contrast to many other open-source conceptual design platforms.FindingsIn this study, authentic General Dynamics F-16 Fighting Falcon and McDonnell Douglas F-15 Eagle data were used as input to the system, and advanced geometric and/or performance graphs were obtained and compared to the literature where a good agreement of the results was observed. These results with regard to the aircraft performance are typically product specific and quite rare in the literature. These data obtained by use of the software during the aircraft design are, thus, of major interest, especially for the design of new aerospace platforms. In this study, all of these graphs (especially the remarkable V-n diagram) are obtained on one platform.Originality valueThe aircraft conceptual design and analysis system software provides information and suggestions regarding the requirements for reducing the overall design time, reducing the design costs and creating an optimized design at the early phases of a project by optimizing the aircraft development process within just one convenient, that is, user friendly, platform, where it uses a combination of varying methodologies. Besides presenting one interface, which is quite typical for conceptual design tools, it allows applications of methods like vortex lattices and finite differences for obtaining aerodynamic performance parameters.

Constrained Form-Finding of Tension–Compression Structures using Automatic Differentiation

This paper proposes a computational approach to form-find pin-jointed bar structures subjected to combinations of tension and compression forces. The generated equilibrium states can meet additional structural and geometrical constraints via gradient-based optimization. We achieve this by extending the combinatorial equilibrium modeling (CEM) framework in three important ways. First, we introduce a new topological object, the auxiliary trail, to expand the range of structures that can be form-found with the framework. Then, we leverage automatic differentiation (AD) to obtain an exact value of the gradient of the sequential and iterative calculations of the CEM form-finding algorithm, instead of a numerical approximation. Finally, we encapsulate our research developments into an open-source design tool written in Python that is usable across different CAD platforms and operating systems. After studying four different structures –a self-stressed tensegrity, a tree canopy, a curved bridge, and a spiral staircase– we demonstrate that our approach enables the solution of constrained form-finding problems on a diverse range of structures more efficiently than in previous work. • A computational form-finding method is extended to enhance the form generation of spatial structures in static equilibrium subjected to tension and compression forces. The output forms can satisfy combinations of force and geometric constraints via gradient-based optimization. • A new topological modeling object, the auxiliary trail, is presented which simplifies the representation of a structure as a valid input to the method herein extended. • Automatic differentiation (AD) is leveraged to obtain an exact value of the gradient of a sequential and iterative form-finding algorithm with marginal human intervention. The application of AD leads to significant computational performance gains, especially when solving large constrained form-finding problems. • A standalone, open-source design tool is developed which enables the formulation and the solution of constrained form-finding problems in plain and simple Python code. The design tool is readily usable on three different operating systems and on three distinct 3D modeling software environments.