A Computer Vision Approach for Automatically Mining and Classifying End of Life Products and Components

The authors of this work present a computer vision approach that discovers and classifies objects in a video stream, towards an automated system for managing End of Life (EOL) waste streams. Currently, the sorting stage of EOL waste management is an extremely manual and tedious process that increases the costs of EOL options and minimizes its attractiveness as a profitable enterprise solution. There have been a wide range of EOL methodologies proposed in the engineering design community that focus on determining the optimal EOL strategies of reuse, recycle, remanufacturing and resynthesis. However, many of these methodologies assume a product/component disassembly cost based on human labor, which hereby increases the cost of EOL waste management. For example, recent EOL options such as resynthesis, rely heavily on the optimal sorting and combining of components in a novel way to form new products. This process however, requires considerable manual labor that may make this option less attractive, given products with highly complex interactions and components. To mitigate these challenges, the authors propose a computer vision system that takes live video streams of incoming EOL waste and i) automatically identifies and classifies products/components of interest and ii) predicts the EOL process that will be needed for a given product/component that is classified. A case study involving an EOL waste stream video is used to demonstrate the predictive accuracy of the proposed methodology in identifying and classifying EOL objects.

A Multidisciplinary Framework to Model Complex Team-Based Product Development

This paper investigates a multidisciplinary framework that simulates design decisions in a complex team-based product development in which engineers simultaneously work in a team project and individual projects. The proposed framework integrates cooperative and noncooperative design models with (1) equilibrium analysis, (2) uncertainty modeling based on behavioral game-theory results, and (3) decision-making using decision analysis. In the proposed framework, noncooperative design is used to simulate engineers’ decisions about team project commitment and to analyze potential free-riding; cooperative design is used to model design outcomes when engineers collaborate in the team project; equilibrium analysis and behavioral game-theory results are used to infer about other engineers’ decisions; and decision analysis is used to calculate expected values of decision alternatives. The proposed framework and the design decision-making model are illustrated using a pressure vessel design as a team project conducted by two engineers: a design engineer and a materials engineer.

Assessment of Products Future Reusability Based on Consumers Usage Behavior: Implications for Lithium-Ion Laptop Batteries

Product reuse is a recommended action toward sustainability. However, the profitable reusability of End-of-Use or End-of-Life (EoU/L) products depends on how consumers have used them over the initial lifecycles and what are their EoU conditions. In addition to consumers’ behavior, product design features such as product durability has an impact on the future reusability. In this paper, a data set of Lithium-ion laptop batteries has been studied with the aim of investigating the potential reusability of laptop batteries. This type of rechargeable batteries is popular due to their energy efficiency and high reliability. Therefore, understanding the lifetime of these batteries and improving the recycling process is becoming important. In this paper, the reusability assessment is linked to the consumer behavior and degradation process simultaneously through monitoring the performance of batteries over their lifetimes. After capturing the utilization behavior, the performance-based stability time of batteries is approximately derived. Consequently, the Reusability Likelihood of batteries is quantified using the number of cycles that the battery can be charged with the aim of facilitating future remarketing and recovery opportunities.

Casimir and Van Der Waals Effects on Parametric Resonance of Bio-NEMS Circular Plate Resonators

This paper deals with Casimir and van der Waals effects on the frequency response of parametric resonance of electrostatically actuated NEMS circular plates for bio-sensing applications. The bio-NEMS resonator consists of a clamped circular elastic plate over a fixed electrode plate. A soft AC voltage of frequency near natural frequency between the plates gives an electrostatic force that leads the elastic plate into vibration which leads to parametric resonance that can be used afterwards for biosensing purposes. Frequency response and the effects of Casimir, and van der Waals forces on the response are reported.

An Optimization Model for Manufacturing Systems in an Uncertain Environment

This paper examines a flexible job shop problem that considers dynamic events, such as stochastic job arrivals, uncertain processing times, unexpected machine breakdowns and the possibility of processing flexibility. To achieve this goal, a new agent-based adaptive control system has been developed at the factory level, along with advanced decision-making strategies that provide responsive factories with adaptation and reconfiguration capabilities and advanced complementary scheduling abilities. The aim is to facilitate operational flexibility and increase productivity as well as offer strategic advantages such as analysis of factory development options by simulation. The feasibility of the proposed system is demonstrated by simulation under various experimental settings, among them shop utilization level, due date tightness and breakdown level.

A Novel Capacitive Sensing Principle for Microdevices

Conventional capacitive sensing places significant limitations on the sensor design due to the pull-in instability caused by the electrostatic force. The main purpose of this study is to examine a low-cost novel capacitive sensing principle based on electrostatic balance which promises to avoid these design limitations. The approach uses an asymmetric electric field on a structure with fingers that can generate a repulsive force while the gap is low and create an attractive force while the gap is large. The size and thickness of the fingers are also responsible for creating repulsive or attractive forces on the structure. This approach has recently been applied successfully in the design of capacitive actuators to provide a repulsive driving force. A new design principle for capacitive sensing is described that avoids pull-in instability by designing the fingers such that the structure is at the equilibrium.

Polymeric Micro-Filter Fabrication Using a Micro Injection Moulding Process

This paper reports on fabrication and characterization of a micro-filter for hearing aid, dialysis media and inhaler. The micro-feature specifications consist in a diameter of 2.3 mm, a thickness of 0.2 mm and it is composed by a mesh with grid of 80 μm and ribs with width of 70 μm. The proposed micro-filter is fabricated by micro injection moulding process adopting a steel mould manufactured by micro Electrical Discharge Machining process (micro EDM). Different polymeric materials (POM, HDPE, LCP), particularly indicated for the injection moulding applications due to their flowability and stability, are tested and evaluated in relation to the process replication capability. Since the polymer micro-filter is made of a complex grid of micro-ribs, the injection moulding process must ensure complete filling of the micro-parts, preventing any defects (i.e. premature solidification, incomplete filling, flash and air traps). To this aim, different system parameters configurations (melt and mould temperature, injection velocity, holding time and pressure, cooling time, pressure limit) are tested for obtaining acceptable part in all polymers grade. Finally, the component is dimensionally characterized by confocal microscopy and its filtration capacity is then verified. Although the feature complexity was high, the results showed that the object could be successfully replicated by filling completely the micro cavities with two of them: POM and HDPE. The most significant parameters influencing the part filling were the mould temperature and the injection velocity. These findings allow to further optimize the micro-injection process parameters to obtain a high quality product.

The Effect of Geometry on the Velocity and Drag Force of Catalytic Micro/Nano-Rockets

The hydrodynamic behavior of synthetic self-propelled catalytic micro/nano-rocket moving in low Reynolds number flow is studied theoretically. The inclination angle of the bubble departed from the micro/nano-rocket is related to the radius of the micro/nano-rocket. A unified formula of the drag force for cylindrical, cone-frustum and double truncated cone shapes micro/nano-rocket have been derived. The effect of geometric shapes on the velocity and the drag force is identified by comparing with three circular cross-sectional types of micro/nano-rocket. The average velocity is found to be strongly dependent on semi-cone angle, length, radius of the micro/nano-rocket, the H2O2 concentration and the drag force. This model provides a proficient explanation for propulsion mechanism of a catalytic micro/nano-rocket. This work can be used to optimize catalytic micro/nano-rockets design, which may have potential applications in biomedical and environmental engineering.

Beyond Optimal Sequencing: Defining Part Orientation and Worker Allocation in Assembly

Assembly Sequence planning is a tedious but crucial task in manufacturing a product. A good assembly plan will lead to minimum wasted time and maximum capacity of resources. Typically, research in Automated Assembly Planning and Assembly Sequence Planning (AAP and ASP) only define the sequence that the parts should be assembled with no information for specifying additional details to make the plan complete and optimal. In this paper we introduce a post-processing step (after the sequence of parts has been found) with focus on optimal part orientation and worker allocation. The paper has two main sections: the first section uses Dijkstra’s algorithm to obtain part orientation with minimum assembly cost. For the second part of the paper, a novel approach is proposed based on a line balancing technique to find the minimum number of workers needed to achieve the minimum make-span time. These necessary details in AAP give real time feedback to designers to analyze their design with production and assembly line information.

Optimal Allocation of Worker Hours to Competing Design Projects to Meet Value Growth Targets

Value creation is the motivating principle of lean product development processes. Set-based concurrent engineering has been proposed to improve product development efficiency and stimulate innovation. However, this approach can lead to inefficient resource utilization because it promotes the development of competitive designs, and effective worker time allocation is a real need in complex design projects. This paper looks at one aspect of resource allocation: optimally assigning limited manpower to competing design projects using a project value growth model that characterizes the translation of work-hours into developed value. While resource allocation methodologies have been proposed before, this paper adds to these efforts by including the lean principle of value together with worker capability when delivering project work and formulates the solution as a predictive control problem. The optimized allocation solution can give guidance to project managers if it is necessary to add overtime or change scheduled completion dates if target value growth is missed because of scarce resources.