My name is Andy, and I am a rising senior at Lowell High School. I became interested in Bluestamp Engineering because of my interests in mathematics and physics, as well as my involvement in my high school FIRST Robotics team. My starter project is a light-seeking robot, which is a small robot that uses photoresistors to adjust resistances and turn motors in the presence of light. My first completed main project is a micro-wind turbine, which uses the wind to turn a stepper motor, which powers an LED. My second main project is an omni-directional robot, which has both directional and rotational movement that are controlled by a wireless PS2 Controller and utilize Arduino Uno code.
If you would like to make these projects, I have attached the following documentation below:
Bluestamp Engineering Reflections
When Mr. Simon, my AP Computer Science teacher, introduced my class to Bluestamp Engineering, I was excited. I had a lot of fun with computer science, physics, and mathematics, and I incorporated all of this in Lowell High School’s FIRST robotics team. However, I did not have much experience in hands-on engineering, and electronics was a completely new language for me. So even though I was very sure that I wanted to pursue engineering, because of my lack of experience, I was a bit nervous about the program when I saw the seemingly impossible work that previous students had done.
However, I actually underestimated my capability to do engineering. There is no doubt that engineering is difficult. I cannot list all the different problems that I had faced in this program, including many broken parts, shorted circuits, unresponsive receivers, and incorrect coding. But despite all of these problems, I was able to grow so much both in intellect and in character. For mechanical engineering, not only was I able to be more familiarized with tools such as power drills, heat guns, jigsaws, and Allen keys, I was able to familiarize myself with basic mechanical parts. Before this program when I looked at the bill of materials, I was very confused about the parts. What are the differences between flat washers, lock washers, and thrust bearings? Not knowing these basic mechanical components well was inhibiting my ability to perform well for my robotics team, so when I return to the team, I believe that I can take a more important role in the mechanical design of the robot. For electrical engineering before this program, all I knew were basic equations and components that I had learned in my physics class. All I knew were equations such as V=IR, P=IV, P=I^2R, and the equations for equivalent resistances, as well as the appearance of resistors and capacitors. I never knew how to make connections of any sort, let alone knowing how to do complicated wiring between the breadboard to the Arduino. However, after this program, I am able to learn how to do wiring very well on the breadboard, knowing where to attach the wires between each other horizontally and vertically, as well as connections to the red rail (+ end) and blue rail (ground). And finally for coding, I was able to challenge myself in programming the Arduino. The basic coding for the Arduino was not difficult, as it seemed very similar to Java programming in my AP Computer Science class in the past. However, when I was doing the coding for my omni-directional robot, in which I had to use a lot trigonometric functions to control the robot, it was difficult to program. However, eventually after geometric analysis, I was able to successfully run code to control the robot.
This was all the intellectual growth that I had, but it by no means supercedes my growth in personal character. For both the wind turbine and the omni-directional robot, there were many broken parts and unresponsive receiver-controller connections, causing me a lot of frustration and forcing me to exercise so much patience. I realized that this was the arduous life of a mechanical engineer because of all the hardware. In addition, there were also many difficulties in assembling the projects. Since there were not that many instructions for the assemblies, I found myself in stuck situations a few times. However, instead of resorting to asking the instructors to solve my problems for me, they instead gave me advice to push me in the right direction. This helped develop my sense of independence in able to solve seemingly impossible problems.
I do not want to end on a sad note, but I will definitely miss Bluestamp Engineering when I leave. The instructors are not only very knowledgeable in their respective fields, but they exercised so much patience and completely overshot any minimum requirements as instructors. They were all willing to troubleshoot problems with us, to the point that some even stayed throughout the afternoon section just to help the students. I definitely admire them for their passion for engineering, as well as their kind character. But aside from engineering, they are also very fun people to have fun with. I remember all the communication between the students and the instructors, allowing me to learn a lot not only about their college lives, but also about their personal lives. I will miss the other intelligent students, who were equally motivated to complete their projects and were able to make projects that were challenging and complicated. I hope to see the growth of Bluestamp Engineering in the future to bring engineering opportunities to previously deprived students such as myself, and I wish Dave and Robin best of luck in the future.
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Main Project Two: Omni-directional Robot
Hello, my name is Andy, and since I finished my wind turbine with two and a half weeks to spare, I decided to start on another main project. This project is the omni-directional robot, inspired by my high school robotics team. This triangular robot has three wheels that can move in any direction controlled by a wireless PS2 Controller. The base of the robot is assembled from the Vex Robotics mechanical parts, mostly made from steel, attached by three motors, motor shafts, and wheels on the sides. The top flat surface of the robot is used to mount the electrical components, which include the receiver, the breadboard, the Arduino Uno, and a 9V battery inside a battery case. This 9V battery is used to power the Arduino Uno. Attached under the robot is a rechargeable 7.2V battery used to power the motors.
The electrical connections were a bit complicated. For each of the motor controllers, the black wire connects to ground, the orange wire connects to the red rail (+), and the white wire connects to the ~ ports on the Arduino Uno. The receiver connections are even more complicated. To make the receiver connections, I had to follow the most bottom diagram and the Ps2x example code in order to do so. The link for the website will be listed at the bottom of the post.
The first milestone was to turn the three motors with preprogrammed code, connecting the orange wires to the 5V/3.3V sources on the Arduino directly without a breadboard. This overall was pretty successful. The second milestone was to accomplish the same task, except with the three motors attached to the breadboard and with the orange wires connected to the red rails. This task proved to be challenging, because two motors turned significantly more than the third, which barely turned. I was able to solve this problem by connecting the ground of the Arduino to a ground port of the breadboard. It seems that this connection solved the problem through a process called pulse modulation, in which the 9V and 7.2V batteries, which offer different pulses, now are connected and can spin all three motors.
The third milestone was to assemble the base of the robot. This process was not too difficult, since the mechanical aspect of building this robot was pretty simple logical since it uses an equilateral, triangular base.
The fourth milestone was to mount the electrical components onto the base of the robot and turn the robot with preprogrammed code. Mounting the electrical components onto the robot was a bit challenging, since many wires came loose in the process, and I had to switch from my small breadboard to a bigger one. Eventually, after taking a lot of care, I was able to attach the electrical components and rotate the robot with preprogrammed code.
The fifth and final milestone was to successful mount the receiver onto the breadboard, program the code, and have the robot move even if the movement is not perfect. To program the code, I had to use intense geometry and trigonometry for the movement of the robot with the left analog stick. Since the wheels must stay parallel to the frames of the robot even during translation, the key was to find the lateral spin for all three motors that will cause the motor to move to a desired location at any input angle. Knowing that in translation, the motor shafts are perpendicular to the frames, I made a right triangle including this perpendicular segment, the unknown lateral movement, and a line connecting the old location of a motor to the new location. Many lines in translational movement are parallel, and because of this fact, it is very easy to find many angles. Eventually, I was about to relate the input angle to the angle between the hypotenuse and the lateral movement, which turned out to be the input angle-120. Knowing that this is an equilateral triangle, the next motor’s is angle-240, and the final one is angle-360, which is the same as the original angle since turning 360 in a unit circle is the same angle.
This project provided me with so much fun and was an excellent learning experience in mechanical engineering, electrical engineering, and coding. I highly recommend to start this project early, earlier than two weeks before the end of the program, since unforeseen problems such as broken controller-receiver connections can exist and obstruct the completion of the project. And remember one important key tip: Do not forget to cover your exposed wires completely with heat shrink. You do not want to have your robot be a fire hazard.
Below is the link to the PS2X website, which has both the receiver connections as well as the PS2 libraries to download for the coding of this robot.
http://www.billporter.info/2010/06/05/playstation-2-controller-arduino-library-v1-0/
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Main Project One, Milestone Four: Modifications to Wind Turbine
I made two modifications to this wind turbine that was originally published by Dustyn. The first modification that I made was adding more LEDs in series to the breadboard. Since I added more LEDs in series, there is more resistance equivalent resistance because in series, resistances add. And since the voltage is assumed to be constant when I turn the wind turbine, and the resistance is increased, by Ohm’s Law V=IR, the current has to decrease. Since the brightness of LEDs depends on the amount of current, the LEDs will decrease in brightness because of the decreased amount of current.
The second modification, which is a theoretical one, is whether the turbine can be used to power something other than LEDs, such as an Ipod. I believe that the turbine will not be able to do so. The main reason for this is that the wind turbine cannot produce enough power to do so, since it cannot provide enough current, even though theoretically, there can be an infinite amount of voltage that can be produced by spinning the turbine at very fast speeds.
Main Project One, Milestone Three: Completion of Wind Turbine
Hi, my name is Andy, and I’m a rising senior at Lowell High School. The main project that I wanted to do was the wind turbine. First, I will explain the parts to the wind turbine. So here are two acrylic disks, aluminum hex standoffs, flat washers, lock washers, 1/4in screws, shaft collars, thrust bearings, more flat washers, acrylic gears, motor, sail holders, aluminum flashings, and the breadboard with all the connections.
When there is wind, the wind gets caught by the sails, which turn as a result. This turns the aluminum rod in the center, which turns the gear that is attached to the rod. This gear is mated with another gear on the shaft of the motor, turning the shaft. When the shaft turns, there is a current that is sent to power up the LED, as shown in my milestone one video.
I did have some problems with the project. The first problem that I had was installing the three aluminum flashings in the slots of the sail holders. The sails rebounded a lot when I tried to bend them, and I remember poking myself a few times actually because of the flashings. In the end, I was able to solve this problem by being strategic in installing them. First, I installed the three flashings in the outer slots to lock the flashings in place. Then, I grasped all three flashings at the center and inserted them into the center slots at the same time.
The second problem, which was also the most major problem, was the motor. The motor worked initially, since I was able to attach it to the breadboard to create the first milestone video. The problem emerged after I tried to remove a stripped screw. I believed that during the process of removing the stripped screw, I used too much force, causing the magnet to be off center and possibly damaging the internal components. The motor refused to turn, no matter how hard I tried to turn it. At first I thought that the problem would be solved if I used a gear to turn the motor shaft instead. Thus, I decided to use epoxy to fill up the center hole of the gear and redrilled it smaller to get a better grip on the shaft. I attached the gear, but the gear still did not turn the shaft. Afterwards, I tried researching a lot online, but most of the solutions about stuck motors involves electrical, not physical problems. I knew this was not an electrical problem because before I could turn the motor when there was no current running through the system, and now I could not. I finally determined it was a physical problem because the coils around the rotor were loosening, which shows a physical problem because when I applied force to rotate the shaft, the coils probably were loosened and spun off-axis. Although in the end I had to order a new motor, I did learn a lot about how stepper motors work in the process. I learned that stepper motors use a permanent magnet called the rotor that is located at the center with electromagnetic coils around it. When a current runs through the motor, one of the many coils is turned on, causing an electromagnetic force that turns the rotor thus, turns the motor. Next, another coil is switched on while others are off, and this process is repeated to create the motion of the stepper motor. With the new motor, I initially tried to unscrew the motor and insert M3 screws into it, which was the major method to attach it. However, I realized that I was stripping the screws too much with the screwdriver, so I instead used epoxy to attach it to the acrylic disk. However, the motor slid off a bit and the epoxy took effect, so I had to chisel out the motor and reglue it with epoxy.
Through this project, I truly faced the arduous life of a mechanical engineer. I expected to finish this project by the end of the second week, but it took one extra week because of the motor. I also did not expect the motor, which I thought to be a simple step of the process because all I had to do was mount it on an acrylic plate, to lead me to a whole extra week of troubleshooting and research. Finally, I did not expect myself to face so many problems with gluing and having the emergence of other problems after the motor worked. However, this experience with working on the wind turbine and the motor taught me important character traits. I have developed an increase in persistence, patience, intellectual thinking, and communication in this project. And when I leave Bluestamp, I will take these traits with me to tackle the world of engineering in the future.
Main Project One, Milestone Two: Solidworks CAD Model of Wind Turbine
Hello, my name is Andy, and I’m a rising senior at Lowell High School. While I was waiting for my last part to arrive, I decided to CAD my wind turbine through Solidworks. Here are the different views of the wind turbine. And when I turn the sails, the rod turns, and because the rod is mated with this gear, this gear spins, and because this gear is in a gear mate with this one, this also spins.
Prior to this program, I worked a bit with Solidworks, but I mainly created parts and only did basic mating, which mainly worked because of luck. However, now I understand how mating works much better than before, especially with the concept of using planes in coincident mating, as well as setting foot in gear mates under advanced mates. However, I did not only improve in mating. I also improved my imagination to create various parts. For example, I experienced a bit of difficulty in creating the sail holders of the aluminum rod, because there are custom-cut and were difficult to CAD. However, I was able to CAD it by working bit by bit on it, starting with the circle in the center, and then slowly using the spline tool to create curves while meticulously measuring out reference lengths to ensure that the sail holder I create is as close to the physical one as much as possible.
The main problem that I had with the model was to get the rod to turn with the sails. I faced so much trouble trying to do the lock mate of the sail holders with the rod, because the potential mate would have overdefined the assembly. Instead of doing the lock mate, I decided to create two planes, one on the rod and one of a sail, and do a perpendicular mate with them. This ended up locking the sails to the rod, and finally, the whole assembly works as the turning of the sails successfully turned the gears.
Attached below are screenshots and a zip file with all the Solidworks components:
Wind Turbine Parts and Final Assembly
Main Project One, Milestone One: Breadboard for Wind Turbine
Hello, my name is Andy, and I’m a rising senior at Lowell High School. The first milestone is to create a working circuit board for the wind turbine. It took me some time to be familiarized with how a breadboard works, but there are essentially a set of simple rules to follow. On the sides with the + and – terminals, the vertical nodes are connected, while near the center, the horizontal nodes are connected. The nodes across gaps are not connected. When the wind turbine spins, this motor spins, acting like a battery and providing current down these four wires. The current then goes across these jumper wires, diodes, more jumper wires, more diodes, and eventually the LED to light it up. Then the current at the end diodes go to the capacitors and finish off at ground. When I spin the motor, the LED lights up!
Attached below are the schematics for the wind turbine:
Starter Project: Light-Seeking Robot
Hello, my name is Andy, and I am a rising senior at Lowell High School. My starter project is the light-seeking robot. First, light reaches the photoresistors, which are the light sensors and offer resistance. The photoresistors adjust the resistance based on the intensity of the light that reaches these photoresistors, by decreasing the resistance under light of high intensities and increasing the resistance under low intensities. According to Ohm’s law, Voltage=Current*Resistance, because the voltage from the battery is constant and the resistance is decreased with light, the current is increased. However, this increased current is not enough to power the motors of the robot. Thus, when the current from the battery goes through the resistors, which offer electrical resistance that drops the voltage, and capacitors, which store charge and offer zero resistance when uncharged and infinite resistance when charged, it eventually passes through the transistors, which amplify the current enough to power the motors. The current continues and reaches the potentiometers, which, just like the photoresistors, are resistors that adjust the resistances, but is done by having the attached trimmers turned. Then the current reaches the second half of the robot, which is symmetric with the first half. There is a second switch on the right side of the robot, which regulates the two modes of the robot. When this switch is flipped to the right, the robot is in the slow mode. This slow speed is because the current takes a path of more resistance in order to power the motors. When the switch is flipped to the left, the robot is in fast mode because the taken path is of less resistance.
In the slow mode, the robot moves in a straight line more consistently because of the decreased interaction between the robot and the ridges of the surface. However, in the fast mode, the robot tends to turn more toward one side because the robot is in contact with the uneven ridges on the surface more oftenly. In each of these cases, the robot successfully seeks light. When I cover the photoresistor on one side, the robot seeks light and thus turns to the side with the uncovered photoresistor.
I did face some difficulty with the robot, especially because I soldered some parts of the robot incorrectly and had to spend time desoldering them. Another problem was that the some copper pieces in the circuit broke, so I had to manually attach wires to connect the circuit. But I have to say, I am proud of what I accomplished in these first few days of Bluestamp. Before attending this program, I knew that I was interested in engineering, though I did not have the experience of building a project completely on my own. In addition, I was focused on mechanical engineering without much experience with electrical engineering. But through this project, I learned many basic skills such as soldering and desoldering, as well as the different electrical components that I knew existed because of my high school physics class, but did not work with hands-on. It seems that electrical engineering might be another aspect of engineering that I want to pursue in the future, and I am excited to start on my wind turbine main project and learn more from the rest of the program.