Murlin Trebuchet Case Studies

Murlin Trebuchet Case Studies

Case Study #1

http://prezi.com/lpxzueiilmh2/murlin-trebuchet/

Positives:

-Dimensions

-Diagrams

-Information is organized

Negatives:

-Not a lot of pictures

-Missing videos

Case Study #2

http://www.instructables.com/id/The-Marshmallow-Trebuchet/step1/A-Little-History-Design-Selection/

Positives:

-A lot of detail

-Dimensions and cost

-Tests of trebuchet

Negatives:

-Some pictures did not load

Sumobot

 

 

 

 

 

Sumobot

 

 



Direct Drive

Gear Drive

 

 The sumobot project consisted of building a sumobot that would be able to make a successful loop around a course.  We were given wood, motors, and access to different types of wheels.  Our group decided to make our sumobot vertical.  At first we used the concept of gear drive, but when we test the car, it did not move.  We concluded that there was too much friction from the gears, therefore we decided to switch to direct drive.  We also believed that the wheel in front of our car hindered our ability to steer, so we removed it and put a ping pong ball in its place.  The ping pong ball had too much friction and the car was not able to move at all.  We also switched from front wheel drive to rear wheel drive because the sumobot moved faster.

 

Only two groups were able to receive a time for their lap around the course.  Group one and group two completed the lap, however groups three, four (my group), and five did not.  Group one received a time of 2 minutes and 24 seconds, and group two received a time of 2 minutes and 50 seconds.

 

Based on observation, our group would make many improvements to our sumobot.  First, we would have made the wheel base longer so we could have a  better ability to steer the car.  Next, we would use smaller wheels for more control.  Also, we would try to fix our gear drive to have less friction and be more efficient. Lastly, we would use more powerful motors/batteries.

 





Our Sumobot



Art Structure

 

Art Structure

 

 

Magnet Fastener

 

Bridge made out of magnets

 

 

 

The project assignment was to build an art structure using a specific fastener, and using only that fastener.  The possible fasteners were rubber bands, paper clips, thread, magnets, bamboo skewers, wood pegs, wire, and white paper.  It was difficult to construct a structure without using a type of glue fastener.  My groups design idea was to build a magnetic bridge that would float from the force of repelling magnets.  Unfortunately, our magnets were not strong enough to hold up the weight of our wood.  Despite this conflict, the design was successful in looking like a bridge.  Other groups built structures like field goal posts, a robot, a manaquine, a fountain, and a house.  All of the structures were interesting because they used their fasteners in many different ways.

Build a Compound Machine

Compound Machine

 

 

 

 

 

Our last project was to build four out of the six simple machines. For this project, we had to build a compound machine with the pulley, lever, and crank.  Instead of working to build to a specific mechanical advantage, the goal was to modify the machines to gain the highest mechanical advantage possible.  At first my group only used the lever, and the crank, but after working on the machine, we were able to incorporate the pulley system.

 

Our final mechanical advantage was 285.18N.  We had the highest mechanical advantage in the class! Compared to other groups, we produced our ideas quicker and efficiently.  In fact, other groups looked at out design for ideas of their own, such as the arm of the wheel and axle.  We found that the bigger the arm, the more mechanical advantage. One problem we faced was how to incoporate the pulley into our compound machine.  We finally decided to restring the pulley and connect it to the crank to have a higher mechanical advantage.  Our methods were very successful.

 

The most difficult concept to grasp during this project was how to incorporate all three machines into one working compound machine.  We had to think of many solutions before we found the right one.  When we tested our machine, it was not measurable until we put enough weight as the output force.  Our group was creative and developed a way to hang a 5lb weight from the machine, and even that was not enough weight.  After over 30N as the output force, we gained an input force of 0.11.  We can apply what we learned from this project to future projects.  When working on projects, we always have to be creative and think of many solutions to problems before working.



Simple Machines

Simple Machines

 

 

In this lab we made four out of the six simple machines.  The goal was to have a mechanical advantage of 6 for the lever, inclined plane, and the wheel and axle.  The goal for the pulley was a mechanical advantage of 2. We used a box of nails as the output force.  The nails weighed approximately 4.6 Newtons. We calculated the actual mechanical advantage.  After we found the actual mechanical advantage of our machine, we calculated % efficiency.  To find % efficiency we divided the ideal mechanical advantage by the actual mechanical advantage and then multiplied by

100.

Lever by our group

Inclined Plane by our group



Wheel and axle by our group

Pulley by our group

Without calculating percent error and measuring the machines, the winner would have been Finbar's group.  However, after Mr. Atkins measured the dimensions on each group's lever, our group was the only group not disqualified.  We did not measure every other machine therefore it is not clear who the winner would have been.  It is difficult to determine a winner because of measurements and percent error may be calculated incorrectly, or in our case, not at all.

Not one group got 100% efficency or the exact mechanical advantage we were trying to get.  It is very likely that groups measured wrong.  Also groups did not test the input force, the box of nails, on their machines before finishing.  By testing as you create the machines, you can figure out what you have to change and how far from the mechanical advantage you are. For the next project, I will make sure to test my machines after each modification to ensure the highest percent efficiency.









Reducing 6 Simple Machines to 4

6 Simple Machines

 

 

1. Lever

2. Pulley

3.Wedge

4. Wheel and axle

5.Screw

6.Inclined Plane

 

 

 

 

Why can we reduce 6 to 4?

 

 

An inclined plane is the same simple machine as a wedge, so there does not have to be two different simple machines.  The screw has the same function as the inclined plane and wedge.

Westwood on the Cutting Edge

Westwood On The Cutting Edge

 



Blueprints are used as models for contrustion for placement and configuration.  Although blueprints are great examples of plans for construction, they are 2D.  This is a disadvantage because other aspects of the building are hard to add on to the blueprint.  Blueprints have the right dimensions, but still do not provide a whole building effect.

 

By using new 3D printing technology, architects and engineers now have the ability to enhance the blueprint experience.  3D printers can be used to print a blue print in 3D, to scale.  This gives architects and engineers the advantage to modify designs on a real life scale.  It also gives a better representation of the overall look and layout of the building.  A 3D printed blueprint of a building can help designers to improve blueprints to make structures stronger.  The 3D printer can change the architecture and engineering aspects of building for the better.

Other Possible Projects:
-Solving a rubik's cube with your mind
-3D print a blue print for a building
-Control a micro-processed robot with your mind
-Make a remote controlled car using RaspberryPi
-3D Scan a body part to make prosthetic limbs