Coming to a close

Our housing unit is finally coming together. Pat has glued the housing together, and tomorrow we will attach all of our components

Unfortunately, the gears and beams we ordered never came in, so we're kind of at a loss here. Scrambling to get something useful to use for our central shaft, we accidentally developed a more streamlined way to allow the pistons to slide. Since the laser-cut parts are too rough around the edges and would require extensive sanding, we decided to cut up a soda bottle and use that as a a smooth interior for the piston head to slide up and down in.

Rectanglebear Memo

Team Rectanglebear

Patrick Love

Brandon Rodriguez

Alan Wish

Introduction:

Team Rectanglebear envisions a future that contains an educational model of a combustion engine without requiring combustion. LEGOs were used to construct a central shaft and a portion of the pistons. The piston heads were sketched in SolidWorks and 3D printed. The housing unit was constructed in SolidWorks, laser cut from a sheet of acrylic, and glued together with an epoxy. A DC motor powers the central shaft and a potentiometer allows for analogue adjustments of motor speed. An LCD screen displays the motor speed.

Preliminary Ideas:

Our first thoughts as Team Rectanglebear focused around things we had already seen done. We toyed with the idea of creating a helicopter-like mechanism that hovers at a set distance above the ground, but decided that this sort of idea could go drastically wrong relatively quickly. Spinning blades and crashing expensive components drove us away from this idea. Sticking with some sort of aeronautical idea, we experimented with dirigible concepts. Maybe we could construct a dirigible-based delivery service, or a dirigible-based instrument that plays notes depending on its height. We came to the conclusion that dealing with a floating bag of gas could become a hassle, so we abandoned this idea as well.

Somewhat disheartened, we transitioned from aeronautics to automotive ideas. We could design a remote controlled car, or an autonomous vacuum car similar to iRobot’s Roomba. These projects seemed like they had been done before. We needed some novelty, some originality. That is what Team Rectanglebear is all about. We liked the car idea a lot, but a pre-constructed motor was unsatisfying. That’s when it hit us: A transparent model of a combustion engine. That way, everyone can see and marvel at the ingenuity of the engine.

Design Process:

            Shaft Assembly

As this assembly was made completely out of LEGOs, we could only model the assembly in SolidWorks with the premade parts given to us during Design Lab. This assembly provided a good exercise in mating components. Check out our video of the completed shaft assembly on our blog, www.rectanglebear.blogspot.com . Viewer discretion is advised: the ferocity of the angular bear is contagious.

            Pistons

Since we have a 3D printer at our disposal, we figured 3D printing the piston heads for our project would be fun. Designed by Patrick Love, these stylish piston heads will move vertically inside the housing unit.

            Housing Unit

Made from cut acrylic, these panels are transparent such that the entire motion of the pistons is visible. The back panel consists of our signature, a bear comprised of rectangle cuts, while the side panels consist of bear paws also comprised of rectangles. Two holes were cut from the side panels to allow for the shaft to go through.

            Wiring and Code

A red LED signifies the motor is off. The LCD screen will also display this along with directions of how to turn the machine on. Holding down the button on the breadboard turns on the motor and the LED changes to green as the LCD screen displays the speed of the motor. A potentiometer controls the speed of the motor.

Final Production:

Assembling the LEGO shaft and fitting it within the constructed housing unit was a challenge. Many measurements we originally took on SolidWorks did not transition to the real world. Adjustments for machining error and inconsistencies had to be made in order to get the final piece fitted.

Several days before final assembly, Team Rectanglebear was notified that four out of five top panels had been stolen. This was a hard reality to face, but we held up to our acute reputation. No challenge is too great for a bear with sharp angles. Confident in Professor Sullivan to get our parts re-cut, we continued to brave the challenge.

Wiring proved to be much more challenging than anticipated. Due to the large quantity of wires used in this project, we had to scale up our breadboard. The stock motors from the SparkFun kit had their leads broken off several times during construction, so we had to use a different motor. Compatibility between transistors and this new motor proved to be an issue as well. Altogether, we feel confident that Team Rectanglebear conquered.

 

December 5 , 2013

Alan ' The genie ' Wish  and Brandon ' panda express 'Rodriguez in attendance

Paper

Work on the paper has begun, to be completed by the end of this get together

Parts 

 Some parts where stolen, however if the new parts are manufactured by Saturday , the putting together process will begin. 

Blog 

Updated blog posts that were forgotten about.

Housing video 

November 26 . 2013

Patrick 'the heartbreaker' Love , Alan Wish , Brandon Rodriguez are in attendance.

Code 

The code works and a git hubs link will be up shortly. 

Even though it works some optimization would be nice to have. Debounce was not incorporated , however a button has been found which does not fluctuate while hit. Again while this works it is by no means a final product.  videos will be up shortly. 

Housing 

 The housing has been finalized in Solid Works and will be sent to be laser cut. Team mascot symbol of a bear like object built with rectangles has been adopted  to distinguish our parts.

Video of code working on stock motor 

November 21 meeting

Patrick love , Alan Wisharooni , and Brandon Rodriguez attended.

Piston/Shaft assembly 

is completed and LEGO parts have been counted and requested

 The code

 is on its way, with the on off button and the Red Green Blue (RGB) led lights working in sync. The next step is incorporating the debounce feature and the motor and LCD control.

Housing unit

Solid Work's design has begun. This will be a simple three wall housing with piston walls to keep the pistons straight through travel.

Code Video 

CODE

Today is a good day :

Vacation around the corner and the Arduino code nearly complete ! Here is the code



https://github.com/rectanglebear/Arduino-motor-control-project-

PISTON ASSEMBLY

Here is a preliminary assembly of our engine model. Currently, there are three 'pistons' controlled by one shaft. 


In the near future, we will create piston heads to attach on the end of the beams and create some sort of enclosure. We are still undecided if we want to 3D print the enclosure or layer acrylic. Either way, the enclosure will not be completely closed. This way, viewers can see the pistons in motion. 
Being able to see the pistons in motion makes the system much more interesting. Allowing each component to be in the open is impossible to do in a combustion engine, so our model gives a unique perspective to this concept.