Position, Velocity, Acceleration and Force AnalysisAppendixesSAN JOSE STATE UNIVERSITY Mechanical and Aerospace Engineering Department Design Project: Ink-B-Gone Team Members : Anthony Cacace Edgar Luna-Ramirez Sharin Shafian Course : ME 106 – Fundamentals of Mechatronics Instructor : Dr. Burford J. Furman Semester : Spring 2006i. Abstract The objective of this project was to fulfill the ME 154 and ME 106 project requirements. The requirements for ME 154 were to design a mechanism that had at least two degrees of freedom, that incorporated rotational and translational motion, and that would perform a meaningful task. Furthermore, the requirements for ME 106 were to use a microcontroller, at least one sensor, and at least one actuator to control a mechanism that solved a particular problem. To fulfill these requirements the group designed and built a prototype of a whiteboard ink-removing device. The prototype was tested for it functionality and its performance was evaluated in context of its marketability. In conclusion, the design was found to exceed project requirements and objectives but room for improvements were found to increase the device’s marketability. ii. Acknowledgements We would sincerely like to thank the following people whose help contributed greatly to the outcome of this project. o Stuart Davis for his donations and technical help o Dr. Raymond K.Yee for his technical help o Dr. Burford J. Furman for his technical help 2iii. Table of Contents Title Page Number i. Abstract 2 ii. Acknowledgements 2 iii. Table of Contents 3 iv. Nomenclature 4 1 Executive Summary 6 2 Introduction 8 3 The Solution 3.1) Pre-fabrication Process: Brainstorming 3.2) The Selected Solution 3.3) Gathering Parts, Fabricating and Assembling 10 4 Analysis and Performance Results 27 5 Discussion 5.1) Outcome and Performance 5.2) Recommendations and Future Enhancements 31 6 Conclusions 35 7 References 37 8 Appendixes 37 3iv. Nomenclature Symbol/Variable Description R1Position vector along ground link (link 1) R2Position vector along crank (link 2) R3Position vector along coupler (link 3) a Length of crank b Length of coupler d Length of ground link θ1Angle between link 1 and ground θ2Angle between link 2 and ground θ3Angle between link 3 and ground ω2Angular velocity of link 2 ω3Angular velocity of link 3 d& Linear velocity of the slider block VALinear velocity vector of point A VBLinear velocity vector of point B VABLinear velocity vector of A relative to B VBALinear velocity vector of B relative to A α2Angular acceleration of link 2 α3Angular acceleration of link 3 d&& Linear acceleration of the slider block AALinear acceleration vector of point A ABLinear acceleration vector of point B AtA Tangential component of linear acceleration vector of point A AtB Tangential component of linear acceleration vector of point BAnA Normal component of linear acceleration vector of point A AtB Normal component of linear acceleration vector of point B ABALinear acceleration vector of B relative to A 4AtBA Tangential component of linear acceleration vector of B relative to A AnBA Normal component of linear acceleration vector of B relative to A 51. Executive Summary The objective of our project was to design a mechanism that will erase a whiteboard by the push of a button. The design should also be able to perform this function faster than if it were performed manually by a person. The chief benefit of our device will be its ability to save time and energy in the classroom. To accomplish this task, our team went through many stages of brainstorming and planning. After various designs, we finally settled on what is essentially a four-bar slider-crank linkage system. We chose this particular mechanism because we had studied it in our ME154 (Mechanical Engineering Design) course earlier in the semester, and thus we saw this as a good opportunity to apply what we had learned. We then mounted this linkage system onto a horizontal printer carriage assembly. Our tem also incorporated concepts from our ME 106 (Fundamentals of Mechatronics) class. Three of the four members of our group, excluding Johan Altamirano, are concurrently taking ME 106 this semester. Using an assortment of components such as DC motors, a diode, MOSFET, H-bridge, resistor and opto-interrupters, we were able to program the mechanism’s movements with the help of the Atmel Atmega 128 Microcontroller. The prototype that we built of our design was scaled down for the purpose of this project. The completed prototype is pictured in Figure 1 below. Due to various constraints such as time, money and availability, we were unable to acquire some of the components we originally choose and we were forced to work with what we could find. Thus, we had to make amendments to our project in order to accommodate these factors. Nevertheless, this did not hold us back and we were ultimately able to make adequate adjustments to our project. 6Figure 1: The completed prototype of the mechanical whiteboard eraser 72. Introduction In the beginning of the semester, our group had many brainstorming sessions in order to generate ideas for our project. From a list of approximately 15 ideas, we narrowed it down and eventually settled on the most interesting, innovating and useful device. Our ideas covered a broad scope of topics, ranging a from relaxation device to foldable means of transportation. Finally, our team settled on a ‘mechanical whiteboard eraser.’ A drawing of the final design can be seen in Figure 2 below. Figure 2: Perspective drawing of the design We choose the white board eraser because it satisfied project requirements, it seemed like an marketable idea and it was a product that would be helpful to humanity. As students, the whiteboard is something we see very often in our classrooms. We realized that most times, it takes lecture time away from the teacher to erase the board. We believe this valuable time, and energy, could be put to better use. Furthermore, the background research we conducted brought us to the conclusion that no such device had been invented thus far, and this further underlined 8the need for us to instigate our idea. Designing this mechanical whiteboard eraser would also be our way of saying “Thank you” to all the teachers who have taught us – past, present, and future. In hopes that the mechanical whiteboard