8th Grade Technology

I Can… Describe the problem solving process Present my ideas and communicate through drawing. 2 dimensional drawings 3 dimensional drawings Orthographic drawings Line types Sketches Thumbnail Rough Final Design my CO2 dragster with certain engineering aspects in mind. Understand how aerodynamics effects my designs. Aero-efficiency

Problem Solving Process Identify and define the problem Set goals and Identify criteria Generate alternatives Consider Limitations Select Optimal solution Implement the solution Evaluate and modify To design a new product, the designer and engineer follow the same basic steps. Some steps may be used more often than others. It depends on which steps or design tools will best solve the problem.

Types of Drawings Two Dimensional Sketches Three Dimensional

Sketches

Two Dimensional Length and breadth but no depth. Flat The ability to view objects from different sides is a part of an area of geometry called Spatial Visualization. The skill of visualizing objects spatially is important to many fields of study, including dentistry, architecture, construction, the arts, auto design as well as many other designing and technology fields.

Three Dimensional Appearing to have length, breadth, and depth. Solid

TOP VIEW Front VIEW SIDE VIEW When you peel the shape apart and draw certain views you begin to draw orthographically. Have students come to the board to draw views.

Orthographic Drawing in which the projection lines are parallel. The aim of an engineering drawing is to convey all the necessary information of how to make the part to the manufacturing department. For most parts, the information cannot be conveyed in a single view. Rather than using several sheets of paper with different views of the part, several views can be combined on a single drawing using one of the two available projection systems, first angle, and third angle projection.

Show students a block and compare sides. Discuss dimensions. Discuss different types of lines

Line Types Visible Line Hidden Line Center Line

Product Engineering and Design Too Heavy Too Light VS. Fall apart Stay together Engineering involves predicting the future behavior of a material, or system. Engineers base predictions on known facts, mathematics, and science principles. Product Engineering – means figuring out ahead of time whether a product will be strong enough and work as it should. There are many things to consider, and every detail has to be planned carefully. Maximized Design Thrown together

Mockups Paste-up Shows general size and shape Rough Idea Appearance mock-up Cardboard, clay, plastic, wood ect. Looks like product No working parts The CO2 dragster is a mock-up of the real designs. No working engines or pulleys. Try to design your car so that it could evolve into a real car. Hard Mock-up Most parts work Major parts are not included

Prototypes http://www.conceptcarz.com/ Working Model Testing Design changes http://www.conceptcarz.com/

Aerodynamics Thrust Gravity Drag The scientific study of how air interacts with moving objects. Thrust Once the prototypes are made testing can take place. Some of the testing done on cars relates to how well air moves around it. Forces such as gravity, thrust and drag are important in design. Gravity Drag

Drag Coefficient The aero-efficiency of any shape can be calculated. The lower the CD value the more aerodynamic the moving object.

Students should look for the lowest Drag Coefficient in their design.

References Huth, Mark W. Construction Technology. Glencoe/McGraw-Hill. IL: Peoria, 1997. Fales, Sheets, Mervich, and Dinan. Manufacturing a Basic Text. Glencoe/McGraw-Hill. IL: Peoria, 1986. Fales, Kuetemeyer, and Brusic. Technology Today and Tomorrow. Glencoe Publishing Company. California: Mission Hills, 1988. http://www.conceptcarz.com/