Ship the Chip Sort It Out Pulleys and Force
description
Transcript of Ship the Chip Sort It Out Pulleys and Force
+
Ship the ChipSort It OutPulleys and Force
Christopher Lester
Yvonne PelhamMoshe Kam
D.G. Gorham
TISP: Uruguay
9–10 May 2009
User Handout Day 1
+
Package design and the engineering behind shipping products safely
Exercise 1:
Ship The Chip
3+Ship the Chip
Design a package that will securely hold a potato chip and protect it from breaking when dropped
Construct the lightest package to get the highest score Overall score based on:
Weight of the package Volume of the package Intactness Score
The Challenge
4+Ship the Chip
1. Sketch a design on the worksheet Label your worksheet with Table # and Team Name
2. Construct a model of your package3. At a test station, drop the package from a height of 1.5 meters4. Open your package and examine the chip5. Calculate and record your score6. Using a second kit, redesign and construct a new package
Record the second design on the worksheet
7. Label your package with Table # and Team Name
8. Submit your worksheet and package to the Test Team for overnight testing
Procedure
5+Ship the Chip
Cardboard – 22 cm x 28 cm 10 Craft sticks 6 Cotton Balls String – 91 cm Plastic wrap – 1 sheet of 22 cm x 28 cm 10 Toothpicks Foil – 1 sheet of 22 cm x 28 cm Paper – 1 sheet of 22 cm x 28 cm 1 Mailing label 1 Potato Chip
Materials
6+Ship the Chip
Scissors
Pencils/Pens
Rulers
Digital Scale
Marking pen
Calculator
Clear Adhesive Tape
Masking Tape
Tools and Accessories
+ 7
Intactness score :
100: like new, perfect
50 : slightly damaged; cracked but still in one piece
25 : broken in 2 - 5 pieces
5 : broken in 6-20 pieces
1 : broken into more than 20 pieces; crumbled
Ship the ChipScoring
3
___ _ _ _Intactness ScoreOverall Score
Weight in Kg Volume in cm
8+Ship the Chip We will imbed the package in the smallest-volume
rectangular prism that contains it We will calculate the volume of the prism;
Width x Length x Height For example : 3cm x 4cm x12cm =144 cm3 in the prism
shown below
If your package weighed 100g and had a volume of 800 cm3 and the chip has arrived broken in 3 pieces:
Calculating Volume
3
___ _ _ _Intactness ScoreOverall Score
Weight in Kg Volume in cm
25_ 0.31250.1 800
Overall Score
+
The engineering behind industrial sorting processes
Exercise 2:
Sort It Out!
+ 10
Groups of 2 You are a team of engineers hired
by a bank to develop a machine to sort coins that are brought in by customers.
Must mechanically sort mixed coins into separate containers.
In our experiment we use washers: ½ Inch 1 Inch 1¼ Inch 1½ Inch
Sort It OutYour Turn
11+Sort It Out
How good is it? 1: “Distance” performance index:
A washer that does not get sorted has maximum Derror = 3
Your Turn
½in 1in 1¼in 1½in1
Distance from correct binhere, Derror = 2 bins
11
½
½ ½
½
½ 1½1¼1
1 1 1 1¼1¼
1¼1¼ 1½
1½ 1½
12+Sort It Out
How good is it? 2: “Percentage” performance index:
Your Turn
½in 1in 1¼in 1½in1
11
½
½ ½
½
½ 1½1¼1
1 1 1 1¼1¼
1¼1¼ 1½
1½ 1½
# of washers incorrectly identified
Total # of washers to sort 405%
+ 13
Materials: glue, tape, paper or
plastic plates, cardboard, scissors or hole punch, foil, paper, cardboard tubes
washers
Design (draw) a mechanical sorter that can separate the ½in, 1in, 1¼in, 1½in washers
Input: either Parallel – all washers are
inserted at start of your sorter together; or
Serial – washers are inserted at start of your sorter one at a time
Output: Each size of washer in its own physical container
Sort It OutYour Turn
14+Sort It Out
At your table, choose 2 groups to build a parallel sorter; the other 2 groups will build a serial sorter
You will have 45 seconds to allow your sorter to operate Predict the value of the two performance indices for
your design Construct your sorting mechanism Test it! Can you do better?
Your Turn
+
All about force and how pulleys can help reduce it
Exercise 3:
Pulleys & Force
+ 16
Fixed Pulley Movable Pulley
Pulleys & ForceBasics of Pulleys: Two orientations
+ 17
Pulleys & ForceMechanical Advantage
Mechanical Advantage (MA) isthe factor by which a mechanism multiplies the force or torque put into it.
Ideal MA:
Actual MA:
This movable pulley system has a mechanical advantage of 2
+ 18
Work is the amount of energy transferred by a force acting through a distance
Work = Force x DistanceWork = Force x Distance
A bigger mechanical advantage decreases the force required, but increases the distance over which it must be applied
The total amount of work required to move the load stays the same
Pulleys & ForceWork
+ 19
The ratio between Actual and Ideal mechanical advantage is Efficiency
Frictionless system = 100% Efficiency
Pulleys & ForceEfficiency
+ 20
Pulleys & ForceMeasuring Tension
Spring Scale Calibrate: Hold spring scale
at eye-level and turn adjustment screw until the internal indicator is precisely aligned with the top zero line
Measure: Create a loop in the end of the rope you want to measure tension in; attach spring scale to loop. Hold the spring scale steady and read off the tension measurement.
+ 21
Groups of 2 Develop 2 systems to lift a filled soda bottle
10cm with 1 pulley 2 pulleys
Build your systems Measure the distance the soda bottle
moves and compare it to the distance you had to pull What is the actual mechanical
advantage? Measure the force you must exert on the
string and compare it to the force that is finally transmitted to the soda bottle What is the ideal mechanical advantage?
Calculate the efficiency of each system
Pulleys & ForceYour Turn
+ 22
Now join with one other group at your table
Develop 2 different systems to lift a filled soda bottle 10cm with all 4 pulleys
Build both systems What are their actual
mechanical advantages? Ideal? Which one has a better
efficiency? Why do think that is?
Pulleys & ForceYour Turn