TDJ3M_Material_Selection

include component="page" wikiName="jmcintyre" page="course_tabs_header" include component="page" wikiName="jmcintyre" page="menu_TDJ3M_crumbs" Material Selection | Structural Material Reinforcement | AutoCAD review and practice =Material Selection=

Material selection is a step in the process of designing any physical object. In the context of product design, the main goal of material selection is to minimize cost while meeting product performance goals. Systematic selection of the best material for a given application begins with properties and costs of candidate materials. For example, a thermal blanket must have poor thermal conductivity in order to minimize heat transfer for a given temperature difference. [|source] When considering what material you plan on using for a given project consider the following:
 * 1) Strength/flexibility - is it strong enough to resist forces applied to the object/system? For example: If the goal of the object is to be a wing, we want it to be strong, yet flexible. A wing of cast iron is strong, yet the forces applied to it will ultimately cause it to fail. Aluminum on the other hand is strong and when assembled in the right way, flexible.
 * 2) Weight - it the weight appropriate for the usage? In the case above, you could use steel or aluminum to make the plane wing - both of which have the right rigidity, yet steel is far more dense than aluminum, thus a poorer choice.
 * 3) Cost - it's all well and fine to choose a material whose strength/weight are ideal for the object, but if the cost is so high that the product is untenable then it's not an ideal solution. E.g. Gold is both pliable as well as a fabulous conductor, but cost would prohibit it from being used as electrical cabling throughout a standard house.

In considering both points above designers need quantify the material choice so that the best material can be used for the job. Plotted against one another [|Young's Modulus] (strength/elasticity) is a way of measuring stiffness for elastic materials (even metals can be considered elastic because they deform under pressure). When you plot Young's modulus (YM) against density you get the following result (figure at right). Quickly designers can see ranges of what materials would be ideal for the job.

Case in point: Designing a protective cover for a phone. You could use a pliable, reasonably light material, or use a stiffer, but equally light material.


 * Otterbox: ABS plastic (think sewer pipes) mixed with fiberglass. Young's Modulus value about 0.6GPa. Density about 2000.

-pro's? -con's?
 * TPU: ([|thermoplastic polyurethane]). A moderately flexible, yet tough form of plastic. YM value of about 0.1 GPa, density about 900.

- pro's? - cons?
 * Silicone:Very flexible, very elastic. YM value of about 0.01 GPa. Density of about 1000.

- pro's? - con's?



Assignment # 3 - Material Selection
Goals: You are to make the same shape (e.g. the first letter of your name, an exclamation mark, a symbol) out of 5 different materials. Try to vary the YM value of the materials chosen. We will touch on tool safety with this project and you will get both manufacturing experience and a good grasp of the actual nature of various materials in doing it.

Specifics:
 * On paper, you are going to design your shape and complete:
 * an orthographic projection - complete with both the isometric view as well as the dimensions. The orthographic projection should be at a 1:1 scale.
 * 5 materials will be chosen with a variety of YM values. Make sure that the tools available to us are able to craft the material into your final shape. (i.e. don't choose diamond or hardened steel)
 * Once manufactured, the 5 materials will be showcased on a poster/display that will list:
 * their YM value and density (as best as you can research).
 * sources of the material
 * common uses
 * cost per unit

Evaluation:

Exemplar: [|Exemplar1] [|Exemplar2] [|Examplar 3a]and [|3b]
 * **CATEGORY** || **4** || **3** || **2** || **1** ||
 * **Orthographic Drawing** || Lines meet seamlessly. Projections are evenly spaced. Dimensions are present. There are no flaws in the drawing. || Projections line up at the edges with few flaws in the drawing. || Projections are present, though some aspects don't line up || Lines meet but with much room for improvement. ||
 * 2 point perspective drawing OR isometric drawing || Lines merge seamlessly There are no flaws in the drawing. || Lines merge well .There are generally no flaws in the drawing. || Lines merge properly. There are flaws in the drawing. || Lines generally merge properly however there are multiple flaws in the drawing. ||
 * **Material manufacturing** || Manufacturing of the shape is flawless. || Few flawed markings mar the shape, but otherwise the shape is well crafted. || Shapes are rough but clear enough to be sound. || Shapes are poorly manufactured, are rough, there are stray cuts, or generally don't conform to the set out dimensions. ||
 * **Product layout** || Resulting shapes are well laid out. The design showcases the manufacturing. || The resulting shapes are laid out, though some aspects could be improved. || Aspects of the product are poorly laid out. || The product is shown, but the layout is not flattering in its setup. ||
 * **Material information** || Relevant information appears present and is well researched. || Relevant information is generally present and is well researched. || Relevant information is largely present and is some research has been done. || Information is scant. ||
 * **Use of Time** || Used time well during each class period (as shown by observation by teacher, and documentation of progress in journal) with no reminders. || Used time well during most class periods (as shown by observation by teacher, and documentation of progress in journal) with no reminders. || Used time well (as shown by observation by teacher and documentation of progress in journal), but required reminders on one or more occasions to do so. || Used time poorly (as shown by observation by teacher and/or documentation of progress in journal) in spite of several reminders to do so. ||
 * **Filetype and size** || All elements are present. || Generally all elements are present, and scanned in. || Many present. Some important components missing. || Only a few of the requirements have been met ||

 =Structural Material Reinforcement= Rarely are materials used on their own without some form of reinforcement. Reinforcement may come in one of two ways: 1) **__Composite materials__** - where the material is a mix of constituent materials. There are two types of constituent materials a) matrix and b) reinforcement. One of each is used in making the composite. Some examples of older composite materials are:
 * concrete (lime mixed with aggregate)
 * paper-mache (paper mixed with glue)
 * wood (made of cellulose fibers in lignin matrix)
 * wattle and daub (mix of straw and clay in bricks)

Newer composite materials started with the plastic bakelite in the early 1900's. Commonly used as **matrices** are resins such as polyester and epoxy although glass may be used as well. Modern reinforcements are often natural and artificial fiber. The life of a garage floor is extended 20+ years by the addition of fiber to the matrix.

2) __**Fasteners**__ - used to reinforce the structure AFTER the structure has been built fasteners often amplify the structural strength of the object by a magnitude of 50x or more. Technically most fasteners are ties. Common fasteners are the:

media type="youtube" key="aKpDyfJnxQQ" width="560" height="315"

Gusset Plate:
Gusset plates amplify the structural integrity of joints between members in construction

(example of what happens when a gusset plate fails on the I-35W in Minneapolis) media type="youtube" key="z1uscpZt8EQ?version=3" height="315" width="560" Collapse of I85 bridge in Atlanta media type="youtube" key="arBqt8ERS6I" width="560" height="315"

Joist hanger:
Used to strengthen the interface between hanging members in wood construction (in this case the joist hanger - though in reality there are may types of hangers used in construction).

Ties:
In general the truss plate (or nail plate) is used as a type of gusset plate in wood construction. Ties in general are used in engineering to resist compression. There are MANY many more ties than listed here above.



AutoCAD
//The devil or your best friend?//

AutoCAD (computer-aided-design) is a high-end program that is used by designers the world over to realize their ideas. AutoCAD not only allows you to design in 2D and 3D but it also has, as output options, the ability to send information from your designs to [|CnC routers], and [|3D printers] for modeling.

We will explore the basics of AutoCAD as a tool in our design arsenal.

We will follow [|this basic reference guide]as we begin to head through the world of AutoCAD.



1) Introduction
//[|source]//  Everything that you draw in AutoCAD is exact. All objects drawn on the screen are placed there based on a simple X,Y coordinate system. In AutoCAD this is known as the World Coordinate System (WCS). You must understand this to know how to put things where you want them. Below are diagrams showing you how this system works:
 * The X,Y coordinate system**

In order to work effectively with AutoCAD, you have to work with this system. Until you are comfortable and familiar with it, learning AutoCAD will be more of a chore. Your life will be made MUCH easier once you understand this world-space.

__Here is how it works__: AutoCAD uses points to determine where an object is located. There is an origin where it begins counting from. This point is (0,0). Every object is located in relation to the origin. If you were to draw a line straight out to the right from the origin, this would be considered the positive X-axis. If you were to draw a line straight up, this would be the positive Y-axis. The picture above shows a point located at (9,6). This means that the point is 9 units over in the X-axis and 6 units up in the Y-axis. When you are working with points, X always comes first. The other point shown is (-10,-4). This means that the point is 10 units in the negative X-axis (left) and 4 units in the negative Y-axis (down).

A line has two points, a start point and an end point. AutoCAD works with the points to display the line on the screen. Move your cursor over the picture above and you will see line drawn from the absolute points of (-10,-4) to (9,6).

Most of the time you will not have an indication of where the origin is. You may need to draw a line from the endpoint of an existing line. To do this you use relative points. These work the same way, but you have to add the @ symbol to tell AutoCAD that this next point is relative from the last point entered. If you're using the mouse of course, you need not entirely worry about your coordinates, other than to place the endpoint of your lines. We'll talk more of this later.  AutoCAD measures angles in a particular way also. Look at the diagram below: When drawing lines at an angle, you have to begin measuring the angle from 0 degrees, which is at the 3 o'clock position. If you drew a line at 90 degrees, it would go straight up. The example above (when you move your mouse over it) shows a line drawn at +300 degrees (270+30), or -60 degrees.
 * Angular Measurement**

You might not always have an obvious reference point for 0 degrees. Look at the example below and place your mouse on the image to find out the angle in question.

In this example, you are given information about the lines, but not the angle AutoCAD needs to draw the line from the start point. What you are given though, is (a) the knowledge that 0° is at the 3 o'clock position (b) the knowledge that 180° is at the 9 o'clock position and (c) the angle between 180° and the line you want to draw is 150°. With this information, you can figure out what angle you need. Here is a fool-proof way of getting the angle you need:


 * 1) Start at the 0° position and measure counter-clockwise (+) to 180°
 * 2) From 180°, measure clockwise 150° (-)
 * 3) Consider that you just went +180-150 and use that as an equation: +180-150=30
 * 4) Now you can draw your line using polar coordinates (discussed below)

You can enter points directly on the command line using three different systems. The one you use will depend on which is more applicable for the situation. The first assignment will get you used to this. The three systems are as follows:
 * Summary: Entering Points in AutoCAD**

ABSOLUTE CO-ORDINATES - Using this method, you enter the points as they relate to the origin of the WCS. To enter a point just enter in the exact point as X,Y.

RELATIVE CO-ORDINATES - This allows you to enter points in relation to the first point you have entered. After you've entered one point, the next would be entered as @X,Y. This means that AutoCAD will draw a line from the first point to another point X units over and Y units up relative to the previous point.

POLAR CO-ORDINATES - You would use this system if you know that you want to draw a line a certain distance at a particular angle. You would enter this as @D<A. In this case, D is the distance and A is the angle. Example: @10<90 will draw a line 10 units straight up from the first point.

The three ways of entering coordinates shown above are the ONLY way AutoCAD accepts input. First decide which style you need to use, and then enter as shown. Remember that X is always before Y (alphabetical). Don't forget the '@' symbol when you are entering relative points. Any typing error or omission will give you results you don't want. If you make a mistake all you need to do is CTRL-Z to undo, or press F2 to see your entry to figure out what you did wrong.



2) Drawing and Modifying
//[|source]// AutoCAD allows you to have access to a large number of commands. A general rule is that you will use 20% of the commands 80% of the time. I will start by introducing you to the most common drawing commands. When you combine these with the basic modify commands, you will be able to make elaborate drawings quite quickly. In other words, most of the commands you will use while using AutoCAD are taught in Level 1.

The important thing to remember is that AutoCAD will expect you give it information in a very particular order. The most frustrating thing when you begin using this program is that you will try to do something, but AutoCAD will 'not work'. In most cases, it means that you are trying to input information at the wrong time. This is why it is very important to be in the habit of looking at the command line.

__**The command line tells you what information AutoCAD requires to continue!**__

Your first drawing assignments will be to use the drawing commands in conjunction with the co-ordinate system. These are basic assignments, but it is very important to understand how to give the program accurate information. You will use the following commands:


 * **Command** || **Keystroke** || **Icon** || **Location** || **Result** ||
 * Line || Line / L || [[image:http://www.we-r-here.com/cad/tutorials/level_1/images/line_icon.gif width="40" height="54" align="center" caption="Line Icon"]] || __H__ome > __LI__ne || Draw a straight line segment from one point to the next ||
 * Circle || Circle / C || [[image:http://www.we-r-here.com/cad/tutorials/level_1/images/circle_icon.gif width="32" height="22" align="center" caption="Circle Icon"]] || __H__ome> __C__ircle > Center, __R__adius || Draws a circle based on a center point and radius. ||
 * Erase || Erase / E || [[image:http://www.we-r-here.com/cad/tutorials/level_1/images/erase_icon.gif width="24" height="22" align="center" caption="Erase Icon"]] || __M__odify > __E__rase || Erases an object. ||

By now you have probably seen a colored rectangle appear on your screen when you left-click and the move the crosshairs around. You'll learn all about these in this lesson. AutoCAD uses what's called a selection set to allow you to group objects together and then modify them. For example, if you want to erase several lines, you could press E , pick on the line, press  again and repeat until you're done. Another way would be to press E <ENTER>, and then pick the lines one by one until they are all selected, and press <ENTER>. By selecting a group of objects, you have created a selection set. Whenever you want to modify an object, and are asked by AutoCAD to "select objects" you can create a selection set and then apply the command.

__**REMEMBER TO PRESS ENTER WHEN YOU ARE FINISHED SELECTING THE OBJECTS**__

There are also a few other ways to create a selection set. The most common way is to use a window.

There are two very different types of windows you can use.


 * <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">**DIRECTION** || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">**CALLED** || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">**DISPLAY** || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">**EFFECT** ||
 * <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">RIGHT TO LEFT || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">CROSSING SELECTION || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">GREEN

<span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">(with a dotted outline) || <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">SECLECTS ANY OBJECT THAT EITHER CROSSES THE BOUNDARY OR IS INSIDE IT ||
 * <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">LEFT TO RIGHT || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">WINDOW SELCTION || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">BLUE || <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">SELECTS ON OBJECTS THAT ARE COMPLETELY WITHIN THE BOX ||

<span style="color: #0000ff; font-family: 'Courier New',Courier,mono; font-size: 16px;">**REC** || || <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">__H ome > Draw >__
 * <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">**Command** || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">**Keystroke** || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">**Icon** || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">**Location** || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">**Result** ||
 * <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">Rectangle || <span style="color: #0000ff; font-family: 'Courier New',Courier,mono; font-size: 16px;">**RECTANGLE /**

<span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">__Rectan__g__le__ || <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">Draws a rectangle after you enter one corner and then the second. ||
 * <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">Trim || <span style="color: #0000ff; font-family: 'Courier New',Courier,mono; font-size: 16px;">**TRIM / TR** || [[image:http://www.we-r-here.com/cad/tutorials/level_1/images/trim_icon.gif width="22" height="22" align="center" caption="Trim Icon"]] || <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">Home > __M__odify >

<span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">__T__rim || <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">Trims objects to a selected cutting edge. || || <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">__T__ools > Object
 * <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">Extend || **EXTEND / EX** || [[image:http://www.we-r-here.com/cad/tutorials/level_1/images/extend_icon.gif width="22" height="22" align="center" caption="Extend Icon"]] || <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">Home > __M__odify > Exten__d__ || <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">Extends objects to a selected boundary edge. ||
 * <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">Offset || **OFFSET / O** || [[image:http://www.we-r-here.com/cad/tutorials/level_1/images/offset_icon.gif width="24" height="22" align="center" caption="Offset Icon"]] || <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">Home > __M__odify > Off__s__et || <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">Offsets an object (parallel) by a set distance. ||
 * <span style="color: #009933; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-decoration: none;">Object Snaps || OSNAP / OS / F3 || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">CLICK

<span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">S__n__ap Settings || <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">Brings up the OSNAP dialog box. ||


 * <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">**Command** || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">**Keystroke** || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">**Icon** || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">**Location** || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">**Result** ||
 * <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">Move || **Move / M** || [[image:http://www.we-r-here.com/cad/tutorials/level_1/images/move_icon.gif width="33" height="33" align="center" caption="Move Icon"]] || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">Home > __M__odify > Mo__v__e || <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">Moves an object or objects ||
 * <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">Copy || **Copy / CP** || [[image:http://www.we-r-here.com/cad/tutorials/level_1/images/copy_icon.gif width="24" height="22" align="center" caption="Copy Icon"]] || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">Home > __M__odify > Cop__y__ || <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">Copies object(s) once or multiple times ||
 * <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">Stretch || **Stretch / S** || [[image:http://www.we-r-here.com/cad/tutorials/level_1/images/stretch_icon.gif width="24" height="22" align="center" caption="Stretch Icon"]] || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">Home > __M__odify > Stretc__h__ || <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">Stretches an object after you have selected a portion of it ||
 * <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">Mirror || **Mirror / MI** || [[image:http://www.we-r-here.com/cad/tutorials/level_1/images/mirror_icon.gif width="24" height="22" align="center" caption="Mirror Icon"]] || <span style="color: #313a4c; display: block; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px; text-align: center;">Home > __M__odify > M__i__rror || <span style="color: #313a4c; font-family: Arial,Helvetica,sans-serif; font-size: 13.3333px;">Creates a mirror image of an object or selection set ||

One is a 'crossing window' and the other is a box. If you create the window from right to left, you make a crossing window. This means that any object that crosses the border or is surrounded by the window is added to the selection set. This is shown as a green rectangle with a dotted outline on the screen. If you create the window from left to right, you create a box. Using this method you'll add only the items that are completely within the box. This is shown as a blue box on the screen. The difference is very important.



Assignment # 4 - AutoCAD intro drawings
Using the following links:
 * [|http://www.we-r-here.com/cad/tutorials/level_1/1-2.htm (intro to drawing)]
 * [|http://www.we-r-here.com/cad/tutorials/level_1/1-3.htm (trim/offset/rectangle/extend)]
 * [|http://www.we-r-here.com/cad/tutorials/level_1/1-6.htm (move/copy modify commands)]

you are to recreate the following pictures exactly, including text and dimensions: //(note: the version of AutoCAD used in the tutorial is AutoCAD 2010, but our version of AutoCAD (2007) will work just fine - you'll just need to know where the symbols are in our version)//



__Evaluation__
To submit: 2 AutoCAD files (drawing4a.dwg and drawing4b.dwg).
 * **CATEGORY** || **4** || **3** || **2** || **1** ||
 * **Content** || All steps are followed and the end product is exemplary. || Generally all steps are followed, there are small errors in layers. || Generally the product is as it should be, though there are enough errors in replication that final product is awkward. || Large errors in replication of the product. ||
 * **Use of Time** || Used time well during each class period (as shown by observation by teacher, and documentation of progress in journal) with no reminders. || Used time well during most class periods (as shown by observation by teacher, and documentation of progress in journal) with no reminders. || Used time well (as shown by observation by teacher and documentation of progress in journal), but required reminders on one or more occasions to do so. || Used time poorly (as shown by observation by teacher and/or documentation of progress in journal) in spite of several reminders to do so. ||
 * **Filetype and naming** ||  ||   || File and name formats are correct. || Either file or name formats are incorrect. ||



Assignment #5 - Cranewars!
<span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">We will use the design cycle to come up with a product that will address the following goal:
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">Design a crane, using limited materials, that will be both easy to use and compete in a time trial and able to lift a minimum of a 1kg weight.

<span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 17.6px; text-align: start;">Description:


<span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">Cranes are built with the intention that they remain upright even under strong loads and shear forces. The purpose of this activity is to construct a crane that will remain upright and intact as it picks up 1kg weights and relocates them in an arc 90 degrees to the base of the crane from where they started.

<span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 17.6px; text-align: start;">General Rules:
<span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">The crane must be built entirely in the classroom/shop. The crane is a minimum of 60cm tall. The weights are placed 20cm from the base of the crane. The crane must pivot to deliver the load 90 degrees from the base from where it started. The crane's tower cannot simply be frictionally rotated with no moving parts. All crane manipulation must be made through non-direct interaction with the crane (i.e. controllers. They may be strings, wires, cords, but you can't simply manually swing the boom or the base)

<span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">__There are 2 parts to the competition__: <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">1) See how many 1 kg weights are moved from the 'staging area' to the 'work site' in 60 seconds <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">2) See how much weight the crane can pick up all at once before it breaks.

<span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 17.6px; text-align: start;">Materials:

 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">The crane is to be built out of 10 mm x 5 mm pine strips (roughly 2x6 scaled in metric) bonded by wood glue. You will also be given 2 sheets of white paper. No other materials may be used in the manufacturing of the structure.
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">Other materials may be used for the gripping pieces, rigging and pivot materials but must not be specific to grappling (e.g. you cannot go out and buy a winch and a robotic hand)
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">Cut wood pieces can be of any length - I will typically supply 1m long pieces.
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">10 m of 'scaled 2x6' wood will be supplied to the team.
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">One sheet base will be supplied to the team.

<span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 17.6px; text-align: start;">Construction:

 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">All construction must be completed prior to the test date - allow at least 24h for a full cure before testing
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">Laminating wood members is allowed (but likely you won’t have the extra wood to do so).
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">Glue can only be placed between two separate pieces of wood and in wood gaps. You cannot coat an entire piece of wood with glue without connecting directly to the surface of another piece. When laminating members together, glue may only be placed between the touching wood surfaces. If glue bleeds between the surfaces and/or connections, it must be sanded off so it will not provide rigidity to the member. I will determine if the glue provides support to the structure.
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">Any method of securing the crane to the base is acceptable.

<span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 17.6px; text-align: start;">Crane Dimensions:

 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">The crane must have an interior area of no less than 100 cm2.
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">A sheet of thin wood will be given as a base
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">The crane must exceed, or be equal to, 60 cm in height.
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">The weights will be placed 20 cm. away from the base. Thus the boom arm must be able to reach out 20 cm.

<span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 17.6px; text-align: start;">Testing:

 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">All cranes will be impounded at the beginning of the competition (no work or adjustment may take place once testing begins)
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">Eye protection has to be used since when the crane shatter they could yield fast moving fragments of wood under high speed. TRUST ME.
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">The crane must be able to lift a single 1kg weight. If it cannot, then the crane will have failed with no results.
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">All contestants are expected to follow the engineering rule of ethics (no cheating). Failure to comply will result in forfeiture of a grade. Your crane will be loaded to destruction as demonstrated.
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">In the speed competition, the 1kg weights will be moved as quickly as possible. The winner is the one that is able to move the most 1kg weights from the staging area to the 'work area' in 60 seconds.
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">In the weight competition, the weights will be added to a bucket hanging off the table. Once the structure breaks the highest recorded weight added up to that point will be the one recorded.

<span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 17.6px; text-align: start;">Evaluation:

 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">Before construction begins - an isometric sketch & orthographic projection must be submitted for assessment. After completion, a final isometric drawing and orthographic projection will be submitted with the design report. The isometric drawing will include all relevant details as pullouts. You will use these in guiding your construction.
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">Crane construction - overall design of the finished product will be evaluated including: dimensions, style and adherence to the working drawings.
 * <span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">Self-Evaluation/ write-up.

<span style="color: #000000; font-family: arial,helvetica,sans-serif; font-size: 13px; text-align: start;">General value of various components of the project: [|Exemplar of what the report should look like] //6-(5)4-(3)2-1// || All aspects of the report are present and exemplary || All aspects of the report are present, though may require some work || There are aspects missing and work is required || There are many flaws in the report ||
 * Component || Value ||
 * 1 - Orthographic / Isometric sketches || 4 ||
 * 2 - AutoCAD drawings || 4 ||
 * 3 - Crane construction || 8 ||
 * 4 - Crane load || % of 10 ||
 * 5 -Technical Report || 6 ||
 * **CATEGORY** || **4** || **3** || **2** || **1** ||
 * **Isometric and or Orthographic sketches** || Isometric drawing is flawless - pullouts (notes) include relevant design details || Isometric drawing is good, pullouts are included. Mostly all details are addressed. || Generally the isometric drawing conveys design plans. There are several design elements missing. || Many design elements are missing from the isometric drawing, but overall the design can be understood. ||
 * **AutoCAD File** || Relevant views of the crane are clear || All views are present, though there may be confusion in the drawings || Generally the drawings can lead towards a final product, but there are flaws in which construction details may be obscured || There are large errors in the object views - such that construction will be difficult based on the schematics. ||
 * **Crane construction**
 * (double value)** || Construction of the product is superior. All joints and cuts are careful and deliberate. Product is stylistically superior. || Construction is sound. Cuts and joints may not all be perfect. Product is generally pleasant to look at. || Generally the construction is solid. Cuts and joints as well as style all leave something to be desired. || The construction is weak. Joints and or cuts are mismatched which results in a stylistically inferior product. ||
 * **Technical Report**
 * **Use of Time** || Used time well during each class period (as shown by observation by teacher, and documentation of progress in journal) with no reminders. || Used time well during most class periods (as shown by observation by teacher, and documentation of progress in journal) with no reminders. || Used time well (as shown by observation by teacher and documentation of progress in journal), but required reminders on one or more occasions to do so. || Used time poorly (as shown by observation by teacher and/or documentation of progress in journal) in spite of several reminders to do so. ||