Work
This was a semester-long project from a Machine Design and Manufacturing class. Each piece, excluding one or two, was machined through the use of a manual mill, manual lathe, or Prototrak (or in some cases a combination of various machines).The engine runs on an external heat source. At its fastest, it can hit close to 1400 RPM when heated by a crème Brule torch; which is towards the faster range for similar engines from the class. The bedplate is similar to that of a body builder. To follow this theme, the base is meant to resemble a podium.
The bedplate and the internal displacer were the only two parts that were outsourced. The remaining dozen pieces were machined from either aluminum, brass, or steel (depending on it's application). The magnet in the flywheel was for our hall effect sensor, which grabbed the RPM from the spinning piece.
This class helped me discover my true passion for design and manufacturing.
This watering can project was born from my current Industrial Design course. The only requirement that the watering can had to meet was that it can hold half a gallon of water. I wanted to stick with a round shape to match the organic nature of water. I wanted to focus on the issue of the handle placement due to the pain points that arose from the process analysis of using a watering can. It occurred to me that I always have to strain and bend my wrist when I pour water from the can, this prompted me to look into alternate handle arrangements.
Slowly, the shape of the watering can started to take form. The handle closest to the spout (inlet and outlet point) will allow for the user to carry the device to and from the sink to the garden. The handle further from the spout will aid in the pouring process. As the water gets to a lower lever the user can switch grips and not strain their wrist while pouring.
I knew from the start of this project that I wanted to learn how to vacuum form. I am already fluent with CNC machining, so my plan is to machine a positive interior mold and thermoform a sheet of ABS to my desired shape (black portion). The handles and stabilizing base will be machined from Al 6061-T6 stock.
Figuring out how the aluminum handles fixture to the ABS body is the "fun" part. Since the handles are going to be machined, my plan is to add a flange to the flat portion of the handle and use both halves of the molded body to secure the handles in place. The sketch below show some rough sketches of this ideation process.
The process of machining the handles can be seen above; the piece took close to 2 and a half hours to machine on our Haas 3-axis MiniMill. Some of the operations from the CAM can be seen below. The toolpaths for the various milling operations are represented by different colored lines. The blue and orange paths are the square-mill roughing passes while the yellow pass is the ball-mill finishing pass.
Once the pieces were machined, I did a few post-ops on the handle using the same fixture plate in a different orientation. I purposefully oriented the fixture holes so that the flat handle face would be perpendicular in this flipped orientation (as shown below). This allowed me to clean-up the surface and drill and tap an 8-32 hole for fixturing to the thermoformed shell later in the process.
In order to create a positive mold for the body of the watering can, I bandsawed a large sheet of MDF into a set of smaller pieces which I stacked together. With the aid of some wood glue, I attached the sheets to one another, forming the stock that I would proceed to machine to create the positive mold for each side of the thermoformed can.
The legs of the watering can were turned on a CNC lathe. I designed the legs to have a cylindrical section that have a nominal diameter. This allowed me to hold the part in a collet and perform a few post-ops so that I could tap a screw into the bottom of the piece, allowing it to be held to the plastic mold for the assembly process.
Senior Design is a year-long project in which Mechanical Engineering seniors participate at UPenn. The goal of the project is to build upon what students have learned in their core classes; teams generally consisted of 4 or 5 students per group. Our team's mission was to create a machine that more efficiently processed frozen fruit into soft-serve ice cream with no additives.
The project was an exercise in team dynamics. Without a cohesive and cooperative team, ideas have a hard time making it from the drawing board to the real world.
The Daily Pennsylvanian wrote an article about our project that sheds light on our accomplishments.
Conventional ice cream uses dairy and other added ingredients during the manufacturing process. Taking away these added elements makes it more difficult to achieve an optimal crystal size for the fruit. When dealing with just fruit, we had to break it down into a small enough crystal while maintaining an optimal serving temperature of -10°C. For this reason, we chose to integrate a freezer into the assembly of the system, which created difficult challenges that were unexpected.
The process of making frozen-fruit soft-serve ice cream, or "fruzi" as we referred to it, is currently being done through the use of a champion juicer. We modified the end of the juicer to allow for the tubing in the image. Fruit enters the diagonal end of the tube, the pressing mechanism would occur from the top end, and the hose attached towards the bottom would be for self-cleaning.
The gear box was custom-machined (excluding the gears, which were OTC), as were various other aluminum parts that helped support the structure of the machine. The gears were chosen such that a 90° rotation would result in a 8" vertical translation of a pushing piston.
In order to drive the system, we integrated a handle that was fixtured to the larger gear that ended driving the system. The sketches show some early sketches of our handle and how it fixtures to the driving gear. Currently, the user of our champion juicer needed to exert a downward pushing force in order to push the fruit onto the grinder. Our handle lever is replacing this traditional method of pushing the fruit onto a juicer. Users of our device preferred the lever to the conventional pushing method since it's easier and it's a similar process to what is used on normal soft-serve ice cream machines.
The annual Personal Project is an open-ended project in which each 10th grader at my high school participates. Because I have always enjoyed designing products which potentially have value in the market, I chose to convert a gasoline-powered go kart into a battery electric vehicle (BEV) through the creative use and assembly of recycled parts.
If you hover over each image you'll see the original go kart I purchased on Craigslist.
I stripped the engine from the chassis and welded a base onto the chassis to support the parts I purchased at a junk yard: battery, solenoid, and starter engine. Additionally, I repainted the chassis and rims, installed an accelerator pedal and an emergency brake, and placed a more comfortable seat in place. In the end, I was able to sell the vehicle to a Mercedes-Benz car mechanic for a profit.
The ergonomics of the seat were difficult to significantly alter due to the welded chassis that came with the purchased go kart. However, I was able to attach two sheets of plywood and a cushion to form a car seat. I also added a emergency kill switch within arms reach of the user in order to give the driver more control and to prevent the battery from draining.
The images above show the go-kart's progression through the process, while the image below shows the welding that I took part in to adjust the vehicle's chassis in order to accomodate a battery and a starter motor.
This piece is another deliverable from IPD 501. The render was modeled in Solidworks off of a melted glob of ice cream. It took circa 20 hours to model in its entirety. In order to get it's realistic shape, I took a few side and front view photos of a melted glob of ice cream and used the images to aid in the surfacing process. Below is a SolidWorks rendering of the cone and melted ice cream assembly.
The base (melted ice cream) was machined on a Haas 3-axis CNC MiniMill. Machining time for the base was about 2 hours, and sanding time was roughly 5 hours.
The ball-mill finishing pass gave the piece a scallop height of 0.005". After an extensive 5 hour period of standing and buffing, the resulting finish can be seen in the pictures below.
The cone was 3D-printed in our Additive Manufacturing Lab on our Objet30 Photopolymer Printer, which has a resolution of 0.002". After it's support material was removed, I spray painted it gold for a more cone-like finish.
Imagine being able to feel an article of clothing before you purchase it online or embrace a loved one via webchat. Our team of engineers is currently working to make these ideas into a reality. The project is focused on the development of a small, wireless, wearable devices that captures touch sensations using a proprietary sensor array, through the “sending” unit (below), transmit them, and then replay them using proprietary tactile display technology, through the “receiving” unit across the Internet.
As one of the design engineers on our team, my responsibility is to design and prototype the finger casing that will house our proprietary sensor array while maintaining an aesthetic and ergonomic form factor for the user. This is my sixth iteration in the design of the finger casing.
Our team meets every week to go over progress and next step; this helps keep us ontop of our work and allows us to bounce ideas off another. Below are a few sketches and notes I took during our weekly meeting.
This casing design was dictated by various project requirements:
The prototype in the image below was printed on a Projet 6000HD using VisiJet® SL Clear material. It represents my most recent design iteration. In this iteration, the piece went through some significant iterations from previous models. While it meets a great deal of our design criteria, the design has yet to accomodate various finger sizes; granted, this is of least priority since our purpose for this prototype is to house electronics and test for proper function.
The interior of this most recent model is slightly larger, which makes it more modular for various finger sizes. The ventilated front also makes it easier for users to place the finger in the device.
As part of an Industrial Design course, I was given a block of cherry wood (roughly 1" x 3" x 12") and tasked with creating a letter opener. I created this elegant solution that acts as both a letter opener and a nice desk piece. Below are some sketches that show the evolution of the piece's form. It's core function lies with it's ability to open a letter, which gives rise to a tapered body that slowly comes to a point.
This was my first exposure to wood working in our wood shop. I was able to achieve it's shape through the use of a vertical bandsaw, extensive belt sanding, and even more extensive hand sanding and filing.
The curvy design lends itself to various handheld positions for the user. When asked to hold the letter opener, almost everyone I gave it to held it a different way, while still keeping their hand by the thick end of the piece; this is consistent with how I intended the piece to be held.
The two designs below are very similar in terms of design, but somewhat different in terms of size and finish. The piece on the left is finished with several coats of an acrylic-based varnish, which helps give it a shinier, darker, and more protective finish. The piece on the right is slightly larger and is finished with a gel stain, which was applied routinely over the course of a week giving it a smoother more natural wood finish. I'm happy with the way they both came out.
I decided to put machining and designing techniques to the challenge in creating this gift for my dad for the holidays. The surfboard was machined from aluminum on a Prototrak, while the surfer, fin, and the waves were all cut from acrylic on a laser cutter. Excluding the waves, the rest of the assembly was sand-blasted for a matt finish.
The work of Theo Jansen inspired the design of Ragno, which means "spider" in Italian. The gate of this crawling creature is dictated by the ratio of the lengths of each linkage. The ratio I used for this design is consistent with the "Golden ratio" that Jansen explains in his work.
The components that comprise the spider include 1/8" MDF laser-cut linkages (~115 pieces), 1" 2-56 screws to hold the joints (~40 screws), and 1/4" stainless steel shafts to hold the entire assembly together (5 rods). In total, the assembly took 3 hours.
I ultimately settled on linkage system that used multiple layers of woven linkages to add support and structure to the piece. I have seen this been done before, and noticed that the structures tend to fall down from lack of support, so I wanted to improve upon this design, while maintaining aesthetic.
After iterating through a few different exterior designs (above), I settled on a straight arm system (below) that bulged by the joints, to ensure that the material wasn't too thin that it would fracture upon assembly. The holes were designed to be close-fits if the piece was sandwiched in the middle and threaded if it was on the exterior (last piece that screw comes in contact with).
After assembling the entire structure, I soon realized that there was too much friction in the joints, making it very difficult to move. This is mostly due to the size of the hole in the joints and the draft angles that the laser cutter puts on pieces that are cut from the machine. Future iterations will have post-ops that make each of the holes concentric and bearings in each joint to ensure motion that has less friction.
In my sophomore year MEAM Lab at Penn, our final project involved building and designing a bridge within a 10cm span. The bridge needed to be made from pressfit MDF. The goal was to maximize the strength-to-weight ratio and minimize the deflection. Our team of three, scored third among the 24 teams in the class. The video below shows the bridge testing apparatus using the load produced by the Instron machine, while the bottom picture is a Solidworks rendering of our bridge. An FEA analyses was also done on the bridge model in order to determine the maximum weight bearing load and resulting deflection and fracture point.
I was always bothered by the fact that my external hard drive didn't come with a protective case for on the go use so I kept it's original packaging as a pseudo-case. After a while, it got very annoying to constantly take it out of it's box everytime I wanted to use it. Additionally, I was found it to be a nuissance to use my drive on a plane, train, or without a table to rest my flash drive. This case I designed solves both these issues in a very effective manner.
The case is comprised of 8 separate laser-cut pieces of acrylic, which were designed to fit snuggly around the drive. The two main rings fit around the center and the "c" members extend around the bottom of the drive. The upper hook-resembling members sit into the "c" members and allows one to rest the case over top of the computer (shown below). Enough relief is provided on the hooks to accomodate any Apple computer.
An added bonus to the hook design is that the accompanying chord can be wrapped around the device; making it easier stow both pieces away with one another when not in use.
This was a quick and dirty solution, which took a few hours to execute from design to iteration tod finished prototype. With more time, there are a number of tweaks I would make to the Spider Case's design.