Cube Module Research Articles

Environmental Temperature Effect on Hydraulic Behavior and Stability of Shallow Slopes

This study established a study framework to quantify the safety factors of unsaturated shallow slopes at different temperatures. This study is based on a non-isothermal soil water characteristic curve model quantifying the temperature-dependent hydraulic properties of soils. The hydraulic coupling analysis models HYDRUS 2D and The Slope Cube Module were used for finite element modeling. A slope stability analysis was performed based on the local factor of safety (LFS) theory. An increased temperature decreased the soil matric suction, suction stress, effective stress, and LFS, weakening the soil strength. Slope modeling analysis showed that soils were dominated by different water retention mechanisms before and after rainfall infiltration, and the trends caused by temperature changes also changed accordingly. This study provides insights into the relationship between soil mechanical properties and temperature, which is valuable for maintaining soil stability and preventing geological hazards.

Reconfiguring Non-Convex Holes in Pivoting Modular Cube Robots

We present an algorithm for self-reconfiguration of admissible 3D configurations of pivoting modular cube robots with holes of arbitrary shape and number. Cube modules move across the surface of configurations by pivoting about shared edges, enabling configurations to reshape themselves. Previous work provides a reconfiguration algorithm for admissible 3D configurations containing no non-convex holes; we improve upon this by handling arbitrary admissible 3D configurations. The key insight specifies a point in the deconstruction of layers enclosing non-convex holes at which we can pause and move inner modules out of the hole. We prove this happens early enough to maintain connectivity, but late enough to open enough room in the enclosing layer for modules to escape the hole. Our algorithm gives reconfiguration plans with <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">O</i> (n <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) moves for n modules.

High speed Power efficient Vedic arithmetic modules on Zedboard‐Zynq‐7000 FPGA

SummaryHardware implementation of dedicated arithmetic modules is inevitable for any signal processing system development and computational complexity of such modules could be significantly reduced with improved performance by utilizing Vedic algorithms. Five novel Vedic arithmetic modules for multiplication, square, cube, square root, and cube root are implemented on Zedboard Zynq‐7000 FPGA. A novel 4:2 compressor that uses only primitive gates in critical path is proposed to reduce partial products in the Urdhwa Tiryakhbhyam parallel multiplier achieving the best performance reported so far. Elimination of recursiveness in Antyayordashekepi‐Dwanda squarer results in reduced area while modified Dwanda squarer results in reduced delay. Anurupyena cubic module with 4:2 and 5:2 compressors is implemented from which the one with 4:2 compressor provides the least delay with more than 50% reduction with respect to that of reported cube modules. Modified Vargamula square root and modified cube root modules are also implemented incorporating pipelining, priority encoder, and padding of zero's to achieve better performance. In addition to the delay, in terms of area occupancy, power, and energy consumed (power‐delay‐product), better or comparable performance is also achieved by all the above‐mentioned modules implemented. The dedicated multiplier is used in a 64‐point FFT Implementation and results similar to existing structures are obtained.

Numerical simulation of a three dimensional electroosmotic micromixer with a flexible and controllable Rubik's cube module

Based on the incompressible Navier Stokes equation (N-S) and the coupling principle of laminar flow and electric field, a new 3D electroosmotic micromixer with a variable module is designed in this paper. A microchannel is designed throughout the variable module to improve the mixing efficiency. The mixing efficiency of the electroosmotic micromixer in different directions, different positions, different alternating voltages and different times was studied. It can be seen from the simulation results that under the influence of electric field, the number, size and position of vortexes formed by the fluid in the microchannel are different. When the Reynolds number (Re) < 10, the electroosmotic micromixer shows a good mixing effect. When Re > 10, most of the micromixers with several torsion modes show a rapid downward trend. Different from the other variable methods, when the first variable module is rotated in the YZ plane, the mixing efficiency decreases slowly and changes steadily, and the maximum mixing efficiency can reach 98.89%. The new electroosmosis micromixer has a smaller pressure drop and provides high flexibility for rapid mixing and a very stable high mixing efficiency.

An Introduction to Design Studio Experience: The Process, Challenges and Opportunities

This paper explores design education in studio settings and presents insights from a design studio based on parametric design thinking. The first-year design studios are essential parts of the architectural education. In these studios, design decisions are taken on a more abstract level, there are less constraints, and the exercises are designed to explore the potentials of design, within the framework of various scales, ranging from human to building, and then to urban. The Introduction to Design course is constructed with interconnected exercises based on concepts such as modularity, the parameters of the human body and spatial perception. The first exercise is designing an architectural structure through parametric thinking. The second exercise is about exploring the design potentials of cube modules with each other, with a rule-based design approach. To better understand the importance of ergonomics in design, the third exercise focuses on the concept of movement through the human body. The aim of the fourth exercise is to study a physical environment and to investigate spatial perception in the built environment. The main aim of this design studio is to teach design with parametric design thinking while focusing on improving the cognitive skills of the students. An Introduction to Design studio experience that is formulated according to these features is described in this study.

An Introduction to Design Studio Experience: The Process, Challenges and Opportunities

This paper explores design education in studio settings and presents insights from a design studio based on parametric design thinking. The first-year design studios are essential parts of the architectural education. In these studios, design decisions are taken on a more abstract level, there are less constraints, and the exercises are designed to explore the potentials of design, within the framework of various scales, ranging from human to building, and then to urban. The Introduction to Design course is constructed with interconnected exercises based on concepts such as modularity, the parameters of the human body and spatial perception. The first exercise is designing an architectural structure through parametric thinking. The second exercise is about exploring the design potentials of cube modules with each other, with a rule-based design approach. To better understand the importance of ergonomics in design, the third exercise focuses on the concept of movement through the human body. The aim of the fourth exercise is to study a physical environment and to investigate spatial perception in the built environment. The main aim of this design studio is to teach design with parametric design thinking while focusing on improving the cognitive skills of the students. An Introduction to Design studio experience that is formulated according to these features is described in this study.

Design and Structural Analysis of a Control Moment Gyroscope (CMG) Actuator for CubeSats

Following a global trend towards miniaturization, the population of nano- and micro-satellite continues to increase. CubeSats are standardized small size satellites based on 10 × 10 × 10 cm cube modules (1U) and are becoming sophisticated platforms despite their very small size. This paper details the design and the structural analysis of a Control Moment Gyroscope (CMG) actuator for agile CubeSats with a physical size up to 12U, which require high torque actuators. CMGs have inherited torque amplification capabilities and the recent advances in motor miniaturization make them ideal candidates for small satellite missions with slew rate requirements. The system’s requirements are derived based on conceptual agility requirements for an agile (highly maneuverable) CubeSat which needs to achieve a 90° maneuver in 90 s. With specific cost, mass and volume requirements, the proposed CMG design is based on some of the smallest available off-the-shelf electric motors and uses a light aluminum casing design. The proposed design uses stepper motors for the gimbal mechanism as a low cost, compact and low power solution, contributing to an overall low mass of the full CMG cluster. Static and dynamic analyses were performed to assess the mechanical integrity of the system for launch loads. Apart from a necessary custom control electronic board, the complete mechanical assembly has been designed including electrical hardware. Analyses demonstrate that the overall stress levels acting on the system are manageable by the CMG design. Bolted joints are critical and should be studied independently as the chosen model created singularities around these areas. Each individual CMG of the designed pyramidal cluster is shown to weigh about 35 g. Using the proposed CMG design with a customized avionics board, the complete CMG system is shown to weigh 250 g and occupies slightly more than ½U volume for a CubeSat, indicating the feasibility of CMGs for agile CubeSats.

Evaluate the Probability of Failure in Rainfall-Induced Landslides Using a Fuzzy Point Estimate Method

Traditional slope stability analysis mostly adopts the limit equilibrium method, which predetermines the slope failure surface and assumes that failure occurs simultaneously at all points of the failure surface. The method is based on the balance of forces and torques. The slope stability is represented by the factor of safety. The lowest factor of safety obtained after repeated analysis indicates the most failure-prone slope surface. However, the factor of safety for only one slope failure surface is obtained when applying this method. The distribution and changes of factor of safety in the interior of the slope are not identified. In addition, the analysis of factor of safety is influenced by the uncertainty in soil mechanical parameters, whereas uncertainty is not quantified in the traditional deterministic analysis. Therefore, a probabilistic approach, which uses the probability distribution function to explain the randomness of parameters, is proposed for quantifying the uncertainty. Nonetheless, when the observation data are not sufficient for determining the probability distribution function, the fuzzy theory can be an alternative method for the analysis. The fuzzy theory is based on fuzzy sets. It expresses the ambiguity of incomplete sets of information using a membership function. Moreover, a correct judgment can be made without verbose iterations. Hence, the aim of this study is to examine the uncertainty in soil mechanical parameters. The membership functions between soil mechanical parameters, i.e., cohesion and angle of internal friction, were constructed based on the fuzzy theory. The fuzzy point estimation was used in combination with the hydrologic and mechanical coupling model on HYDRUS 2D and the Slope Cube Module. The local factor of safety at different depths of the slope was determined using the local factor of safety theory. The probability of failure at different depths was calculated through reliability analysis, which could serve as an early warning for subsequent slope failures.

Toward Energy Autonomy in Heterogeneous Modular Plant-Inspired Robots through Artificial Evolution

Contemporary robots perform energy intensive tasks -- e.g. manipulation and locomotion -- making the development of energy autonomous robots challenging. Since plants are primary energy producers in natural ecosystems, we took plants as a source of inspiration for designing our robotics platform. This led us to investigate energy autonomy in robots through employing solar panels. As plants move slowly compared to other large terrestrial organisms, it is expected that plant-inspired robots can enable robotic applications such as long-term monitoring and exploration where energy consumption could be minimized. Since it is difficult to manually design robotic systems that adheres to full energy autonomy, we utilize evolutionary algorithms to automate the design and evaluation of energy harvesting robots. We demonstrate how artificial evolution can lead to the design and control of a modular plant-like robot. Robotic phenotypes were acquired through implementing an evolutionary algorithm, a generative encoding and modular building blocks in a simulation environment. The generative encoding is based on a context sensitive Lindemayer-System (L-System) and the evolutionary algorithm is used to optimize compositions of heterogeneous modular building blocks in the simulation environment. Phenotypes that evolved from the simulation environment are in turn transferred to a physical robot platform. The robotics platform consists of five different types of modules: (1) a base module; (2) a cube module; (3) servo modules; and (4,5) two types of solar panel modules that are used to harvest energy. The control system for the platform is initially evolved in the simulation environment and afterwards transferred to an actual physical robot. A few experiments were done showing the relationship between energy cost and the amount of light tracking that evolved in the simulation. The reconfigurable modular robots are eventually used to harvest light with the possibility to be reconfigured based on the needs of the designer, the type of usable modules and/or the optimal configuration derived from the simulation environment. Long term energy autonomy has not been tested in this robotics platform. However, we think our robotics platform can serve as a stepping stone towards full energy autonomy in modular robots.

Connecting System for Quick Replacement of Mechatronic SCHUNK Power Cube Modules for Mobile Robotic Systems

The article describes the synthesis of the connecting system for mechatronic modules SCHUNK PowerCube PR70, PR90 and PW90. Emphasis is placed on enabling the quick reconfiguration of the kinematic structure of the manipulator for a mobile robotic system built from these modules. The article describes the process of synthesis of mechanic components of the system, hardware and software ensuring the necessary functions for the realization of connections, detection of orientation of the connected module, securing the flow of energy and data signals and the appropriate response in the control application of the system. This is substantiated by evaluating tests realized on produced prototypes of connecting systems. The article also describes a future outlook for further developments of the connecting system.

A 3D miniaturised programmable transceiver

PurposeTo describe the development of a three dimensional programmable transceiver system of modular design for use as a development tool for a variety of wireless sensor node applications.Design/methodology/approachAs a stepping‐stone towards the development of wireless nodes, sensor networks programme was put in place to develop a 25 mm cube module, which was modular in construction, programmable and miniaturised in form factor. This was to facilitate the development of wireless sensor networks for a variety of different applications. The nodes are used as a platform for sensing and actuating through various parameters, for use in scalable, reconfigurable distributed autonomous sensing networks in a number of research projects currently underway in the Tyndall Institute, as well as other institutes and in a variety of research programs in the area of wireless sensor networks.FindingsThe modular construction enables the heterogeneous implementation of a variety of technologies required in the arena of wireless sensor networks: Intelligence, numerical processing, memory, sensors, power supply and conditioning, all in a similar form factor. This enables rapid deployment of different sensor network nodes in an application specific fashion.Research limitations/implicationsCharacterisation of the transceiver module is ongoing, particularly in the field of the wireless communication platform utilized, and its capabilities.Practical implicationsA rapid prototyping and development cycle of application specific wireless sensor networks has been enabled by the development of this modular system.Originality/valueThis paper provides information about the development work and some potential application areas made available by the implementation of a miniaturised modular wireless sensor node for use in a variety of application scenarios.

A portable array biosensor for detecting multiple analytes in complex samples.

The Multi-Analyte Array Biosensor (MAAB) has been developed at the Naval Research Laboratory (NRL) with the goal of simultaneously detecting and identifying multiple target agents in complex samples with minimal user manipulation. This paper will focus on recent improvements in the biochemical and engineering aspects of this instrument. These improvements have enabled the expansion of the repertoire of analytes detected to include Salmonella typhimurium and Listeria monocytogenes, and also expanded the different sample matrices tested. Furthermore, all components of the biochemical assays could be prepared well in advance of sample testing, resulting in a "plug-and-play" methodology. Simultaneous detection of three toxins (ricin, staphylococcal enterotoxin B, and cholera toxin) was demonstrated using a novel fluidics cube module that limits the number of manipulations to only the initial sample loading. This work demonstrates the utility of the MAAB for rapid analysis of complex samples with multianalyte capability, with a minimum of operator manipulations required for either sample preparation or final analysis.

Connection cube modules for optical backplanes and fiber networks

A modular free-space optical system, called the connection cube, for connecting arrays of electro-optic transceivers and fiber-array connectors is presented. The connection cube module provides bidirectional data transfer between four processing nodes on a cube face and can be used as a basic building block for optical backplanes and interconnect networks. An experimental system for connecting four processing nodes is presented and used to examine alignment and packaging issues. An analysis of the dimensional requirements and scaling capability for systems based on this module is conducted. This analysis shows that, when the connection cube module is adapted to vertical-cavity surface-emitting-laser-based point-to-point fiber-array links currently under development, it can connect up to 14 processing nodes with an aggregate data transfer capacity of 112 Gbits/s with 19.6-W power consumption.