Engineering+Report

Home


 * Introduction**
 * |||| The following report discusses an engineering project designed to study the use of video analysis to measure position (x), velocity (v), and acceleration (a) of a Mouse Trap Racer (MTR). We used common designs to maximize acceleration over a four (4) meter track. The project was conducted in two phases: (1) Construct and test a prototype MTR that used a standard minimum design, and (2) construct and test a student designed MTR that incorporated additional ideas developed during the prototype construction phase. The second MTR is referred to as the “as built” model in the project documentation. ||

‍Procedure
Using a video camera we photographed the MTR as it made its run on the course. The camera operated at the rate of 30 Frames Per Second (FPS). A calibration distance of one (1) meter was recorded with the video. When the video was loaded in the Tracker software, the software used the calibration distance to calculate each x position and the frame rate in FPS to calculate the average velocity between any two frames. In the calculations the sub I ( i ) indicates the value at any particular measured point and time. v i = ∆x i / ∆t or (x2-x1)/(1/30) By using the average velocity between each frame the acceleration is calculated. a i = ∆v i / ∆t or (v2-v1)/(1/30) For each x, v and a, Tracker plotted the position and created a table of values. ||
 * || **Using Tracker Software**

Materials Used: Construction notes: SketchUp: - Materials Used: Construction notes: Sketch-Up:
 * || ===**Building the Prototype MTR**===
 * Balloons(4) about 24 cm string
 * one mouse trap
 * four screws
 * two pen capsoles
 * hot glue gun
 * tape (electrical)
 * 4 CD's
 * 2 zip ties
 * 4 inch rod
 * Most difficult-placing the wheels on straight and not moving
 * start with placing the four screws into the mouse trap by drilling four holes
 * then insert the pen capsoles and use electrical tape as barriers so the capsole can not slide
 * next place balloons on the outside of the four wheels
 * then place the wheels on the pens and secure them with hot glue and electrical tape
 * then zip tie the rod on the spring
 * drill a hole in the rod and attach the string to the rod and then the back axel
 * FINAL: Spin the back axel towards you to collect the string around the axel and let go!
 * Hard to use:
 * using the rotating and sizing tool appropriately
 * also making the screws from scratch
 * make sure your path way for the follow me tool has a stipping point
 * Fun to use:
 * making the screw
 * downloading the mousetrap from google sketch
 * New Tools used:
 * Follow me tool ||
 * || ===**Building the Student Design MTR**===
 * Balloons(4) about 24 cm string
 * one mouse trap
 * two screw loops
 * a pencil
 * 3 styrofoam wheels
 * 2 hot glue sticks
 * steel rod
 * tape (black & white)
 * 2 CD's 12 cm
 * 4 zip ties
 * 4 washers
 * 4 inch rod
 * Originally back wheels were large CD's attached to a wooden axel (which happened to break)
 * Mousetrap taped onto the board
 * Front wheels were modified many times to spin through friction
 * black tape and plastic pieces were added on front and back axels respectively to secure them
 * extra hot glue and washers were added in back while adjusting strength length and bale
 * Ballons were added on wheels to prevent burnout
 * string glued to back axel carefully to ease process of winding the string
 * Hard to use:
 * measuring the parts
 * accurately embedding a cylinder into a rectangle and circle
 * positioning image based texture onto moustrap and target
 * unable to fully represent the student design MTR
 * Fun to use:
 * creating the wheels
 * New Tools used:
 * Follow me tool ||

‍Results and Discussion
Greatest Negative Acceleration= -2.64E2 m/sec^2 Average Velocity= 2.201E2 m/sec =‍As Built**:**= As shown on the charts above, the acceleration of the MTR gradually decreased over the period of 4 seconds while as its position changed at a more consistent rate. ||
 * || **Prototype**:Greatest Positive Acceleration= 2.659E2 m/sec^2

‍Conclusion
Experimental Data and Plots are displayed in the Excel link above. Original analysis here Video Analysis ||
 * || This experiment was both a failure and a success. It was a failure in that our goal turned from the beginning "making the car that has the best acceleration" to a goal of "make the car go one meter." The experiment was a success in teaching us the students how to work with other people in the engineering world. Also its been teaching us how to deal with deadlines, being behind and catching up, and getting used to not receiving homework grades everyday. To improve the experiment Robert and I would have used a stronger string and lighter material so the car would have a greater acceleration. Otherwise, I would say we did as much as we could in the time alloted.

‍Experimental Data
Return to top ||
 * || [[file:analysisMTR.xlsx]]