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Solving FJSSP With a Genetic Algorithm
Get PDFThe Flexible Job Shop Scheduling Problem is an NP-Hard combinatorial problem. This paper aims to find a solution to this problem using genetic algorithms, and discuss the effectiveness of this. Initially, I did exploratory work on whether neural networks would be effective or not, and found a lot of trade offs between using neural networks and chromosome sequencing. In the end, I decided to use chromosome sequencing over neural networks, due to the scope of my problem being on a small scale rather than on a large scale.
Therefore, the genetic algorithm was implemented using chromosome sequencing. My chromosomes were represented as binary strings with reserved bits for the machine and job numbers. This allowed me to experiment with different mutations such as random bit flip mutation and machine job swap mutations.
The biggest benefit of genetic algorithms over heuristic algorithms is the potential for improvement. While greedy gives good results initially, genetic beats out greedy quickly after a small number of epochs. Furthermore, I suspect that genetic algorithms should be much faster than other learning algorithms, but as this is an under-documented metric, I decided to contribute my own results to help document this metric.
For future work, it would be interesting to see how a neural network model would have reacted, and how its time to find a solution would compare to chromosome sequencing. Another interesting topic is a scheduler that can adapt to any variation of the Job Shop Scheduling Problem, as this would be very useful in the real world. One final interesting topic would be to implement some kind of dynamic job loading for this genetic algorithm, as in real world situations, new jobs and tasks get scheduled all the time. But, this is a very complicated problem, thus it is best left to the future
Power Source Characterization for Microgrid Systems
Get PDFOur project aims to develop an affordable and versatile device for testing and analyzing solar panels, batteries, and other voltage sources. The primary objective is to create a portable, cost-effective, and space-efficient device that can be used in various scenarios, including the evaluation of remote microgrids and specialized systems. The device will enable users to gather crucial information about the voltage-current relationship, voltage-power relationship, and other power characteristics of each test source across a range of load currents. One key aspect of the device is its configurability, allowing users to easily modify device parameters and components to accommodate different use cases. This includes supporting lower or higher power sources, adapting to sources with different characteristic curves, and accommodating a wide input source voltage range. By providing users with digestible and valuable data, the device will facilitate the characterization and design of diverse energy systems that utilize these energy sources
Boulevard Apartments - Long Beach, CA
No full textThe proposed development will provide Long Beach residents with more opportunities for housing. The project is located on lots 923 and 927 Long Beach Boulevard in Long Beach, California. Currently, the lots are underutilized and vacant with no existing development on them. The apartment complex will consist of 75 units that include studio apartments, one-bedroom apartments, and two-bedroom apartments. An additional four units will be for qualified, low-income residents. The purpose of this development is to provide quality housing for young adults and families located in the heart of Long Beach
Metamaterial-Based Soft Actuators
Get PDFFor this project the team was tasked with designing a soft actuator that incorporated aspects of mechanical metamaterials. The team’s goal was to demonstrate the feasibility of structural metamaterials in the field of soft robotics and demonstrate a novel response with a final assembly. Also included in the team\u27s discussion are the manufacturing steps, protype tests & results, and suggested future next steps. Following the previous report (critical design review) the team chose to follow the path of designing a continuum robot with metamaterials incorporated into the design. A continuum robot consists of a soft cylindrical body with rigid evenly placed plates and any number of actuating tendons. These tendons, when actuated, cause the plates to draw nearer to one another and the edges to bend to effectively create numerous possible degrees of freedom. To meet the primary goal of incorporating metamaterials the team designed multiple center-body and tip extension metamaterial segments. These segments were joined to the center-body via casting and other methods of joining. With these continuum bodies with different metamaterial inclusions, tests were conducted using a custom-built test stand. The test stand consists of four stepper motors, corresponding electronic microcontrollers and a system of pullies and guide-rods. The primary goal of achieving a unique and novel response with metamaterial inclusions was accomplished, however, full characterization of the test models was unable to be developed due to time constraints and component failures. Manufacturing methods and controller development took precedent in order to develop consistent models and testing for future work on the project
Bespoke Bicycle Enclosure
Get PDFBrian Higgins is an American veteran with retinitis pigmentosa who relies on cycling for transportation. The motivation for this project is to design and manufacture a refined prototype bicycle attachment to support him while biking in the rain and cold. The attachment will serve to enclose him for optimal protection from inclement weather, while maintaining sufficient mobility for daily cycling. Mr. Higgins’ bicycle is equipped with an attached sensor system which assists his visual impairment by using an ultrasonic sensor. Therefore, the attachment cannot adversely affect the function of the sensor system. The project timeline is set at approximately 7 months to complete with a budget of 800 remaining. This final design report represents roughly seven months of research and ideation, and presents the customer needs, background information, design plan and justification, and CAD modeling for the project. We detail our entire manufacturing process along with associated testing for the completed design. Unfortunately, we did not meet all our design goals with the end-product, but we did manage to create a functioning prototype that satisfied all our major constraints. Although our testing did not meet our original standards, this project serves as a first-pass design which can be improved by other engineering teams in the future
Cooled Liquid Rocket Thrust Chamber
Get PDFCooling may affect the thrust output of a small-scale rocket. Little research is published about small-scale rocket performance. We hypothesize the thrust produced varies as the amount of cooling varies. To facilitate assessing this hypothesis, we have designed and built a liquid rocket engine rated for at approximately 25 lbf of thrust. Our objective was to build in parallel with Cal Poly Space Systems, who built a rocket engine with similar specifications except without cooling. Our challenge is to integrate film cooling, so that the effects of cooling may be compared to Cal Poly Space System’s engine which has no cooling. The results will allow for analysis of the effects of cooling on the thrust output of small-scale rocket engines. Utilizing a stacked injector plate design to solve our pressure-drop issues and consequently also solve our mass flowrate issues, we performed more preliminary calculations to justify our decision. We determined suitable material choices with desirable material properties such as the coefficient of thermal expansion and thermal conductivity for our design to be 303 stainless-steel and copper alloy 110. We decided on utilizing copper alloy 110 for our nozzle and combustion chamber, 6061 aluminum for our top injector plate, mild steel for our retaining ring, and 303 stainless-steel for our bottom injector plate. Our finished prototype will be utilized by Cal Poly Space Systems to aid their investigation of the effects of the effects of film cooling on the thrust output of small-scale rocket engines. Hot fire attempts were unsuccessful and resulted in only 15ms of combustion. Recommend more heat to the ignition system to produce self-sustaining combustion to get more effective results in the future
Northrop Grumman Collaboration Project
Get PDFThe Northrop Grumman Collaboration Project (NGCP) is a collaborative club project sponsored by Northrop Grumman for the students of Cal Poly San Luis Obispo (CPSLO) and Cal Poly Pomona (CPP) to create a fleet of vehicles to aid in the simulated rescue of stranded hiker. The CPSLO club is responsible for delivering an autonomous flight vehicle that can suppress a fire and retrieve a payload. Mechanical Design Team of the CPSLO team was responsible for the design of the frame, electronics housing, and payload and fire suppression systems
A Look Back at the Past: 20 Years of Kennedy Library Exhibits
Get PDFExplore past exhibits featured at Robert E. Kennedy Library over the past 20 years
Trajectory-Tracking Control of the Ball-and-Plate System
Get PDFThe Mechatronics group in the Mechanical Engineering department of Cal Poly is interested in creating a demonstration of a ball-and-plate trajectory tracking controller on hardware. The display piece will serve to inspire engineering students to pursue Mechatronics and control theory as an area of study. The ball-and-plate system is open-loop unstable, underactuated, and has complicated, nonlinear equations of motion. These features present substantial challenges for control - especially if the objective is trajectory tracking. Because the system is underactuated, common nonlinear trajectory tracking control techniques are ineffective. This thesis lays out a theoretical foundation for controlling the hardware.
Several important concepts related to ball-and-plate trajectory tracking control are presented. Models of the system, with various assumptions, are given and used in deriving control law candidates. To limit project scope, reasonable control criteria are introduced and used to evaluate designs from the thesis. Several control architectures are explored, these being Full-State Feedback with Integral Action, Single-Input-Single-Output Sliding Mode, and Full-State Feedback with Feed Forward. The mathematical reasoning behind each is detailed, simulation results are shown to validate their practicality and demonstrate features of the architectures, and trajectory similarity measure studies are produced to evaluate controller performance for a wide range of setpoint functions.
The Full-State Feedback with Feed Forward controller is recommended based on its theoretical advantages and compliance with the control criteria over the competing designs. The control architecture has a proof of asymptotic tracking in the linear model, has excellent performance in simulations that use a nonlinear plant model, and produces the most pleasing visual experience when viewed in animation
Analyzing Sport and Gender Issues: Reflective Thoughts of a Cisgender, Heterosexual, White Male Student Majoring in Sports Management
Get PDFThe student author performed a follow-up analysis of an end-of-term reflection essay, in a course that discussed sport and gender, specifically on how sport relates to gender equity and inclusivity issues on micro and macro levels (2022 Fall Quarter, KINE 323: Sport & Gender, Cal Poly, San Luis Obispo). The present submission is a subsequently revised, and improved-upon, write-up of the student author’s KINE 323 term paper (reflection essay), which was revised post-course during the 2023 Winter & Spring Quarters. Through this submission, the student reflects on what he has learned about the following topics covered in the course on sport and gender: i.e., sports history, coaching and administration, feminist theoretical perspectives (e.g., perspectives from radical feminist theory, Black feminist theory), and the experiences of lesbian, gay, bisexual, transgender, queer, and intersex (LGBTQ+) individuals in sports. This reflection essay shows how dialogues and research regarding these topics forced the student author to recognize discrepancies in equality, equity, and inclusion existing in sports, historically, and within his own life. Additionally, through this submission, the student author reflects on how taking KINE 323 has led him to contemplate his position in the interrelating worlds of sports and gender. The ultimate aim of this submission is to create, and or, promote ongoing dialogue focused on fostering positive change, using a reflective analysis of sport and gender by one who identifies as a White, heterosexual, cisgender male and who aspires to positively impact his community through sport