Introduction to Engineering Design. Part C College Credit Performance

Transcription

1 Introduction to Engineering Design Final Examination Part C College Credit Performance Spring 2007 Student Name: Date: Class Period: Total Points: /50 49 of 99 Page 1 of 9

2 DIRECTIONS: Complete each of the following exercises. Record answers to items 1 7 in the spaces provided on the separate answer recording sheet for Part C. Record the solutions to problem 8 directly on the orthographic grid on Page 11 of this document. 1. Identify the three line types (1.1, 1.2, 1.3) indicated on the orthographic drawing below. In complete sentences, explain the specific purpose of each line type as it is used in an orthographic drawing. Record your responses on the answer sheet provided. [6 POINTS: 1 point for correctly identifying each line type, 1 point for explaining the purpose of the each line type] 50 of 99 Page 2 of 9

3 2. Calculate the volume, mass, and surface area of the part below. Then, determine the number of cans (pints) of stain a manufacturer would have to buy in order to apply one coat to 120 wood blocks. Assume each pint will cover 1000 square inches. [4 POINTS 1 point each] Pine Wood Block (Material Density =.02 lbs/in 3 ) 3. Items 3.1 through 3.4 explain the computer-aided design (CAD) work that a group of aerospace engineers has performed on a recent design project. Using only the terms found in the Answer Bank below, identify the missing sketch or feature operation(s) that BEST completes each sentence. [9 POINTS 1 point each] Answer Bank (Note: each item in the Answer Bank may only be used once) axis work planes fillet coil revolve profile rib sweep chamfer thread loft path 51 of 99 Page 3 of 9

4 3.1 The sub-team in charge of wing design used CAD to sketch a series of wingshaped profiles on separate offset 3.1a. The shapes were then merged into a solid by using the 3.1b feature. 3.2 The sub-team in charge of power control used CAD to design the airplane s metal hydraulic lines. A tube cross-section was sketched, along with a carefully designed 3.2a that occurred across several adjacent sketch planes. The 3.2b function was then used to change the sketches into a solid model of a hydraulic line. 3.3 The sub-team in charge of the airplane s suspension systems used CAD to design a hydraulic landing-gear piston. They began by sketching half of the 3.3a of the piston. The 3.3b feature was then used to swing the image around a central 3.3c to form the piston model. 3.4 The suspension sub-team then used the CAD program to place a a on the smaller end of the piston shaft, thus removing the sharp circular edge. The 3.4b feature tool was then used to create a REPRESENTATION of the surface needed to mechanically fasten the end of the piston rod to the rest of the landing-gear assembly. 52 of 99 Page 4 of 9

5 4. Directions: Use the detail drawing below to answer the following parametric equation questions. [5 POINTS 1 point each] 4.1 What would be the parametric equation for dimension d1 if the height (not including the height of the stem) of the object is always equal to the size of its overall width? 4.2 What would be the parametric equation for dimension d4 if the stem is always to be centered within the width of the object? 4.3 What would be the parametric equation for dimension d6 if the stem diameter must always be 40% of the width of the object? 4.4 What would be the parametric equation for dimension d10 if the hole must always have a diameter that is.002 larger than the diameter of the stem? 4.5 What would be the parametric equation for dimension d11 if the depth of the hole must always be.010 in greater than the height of the stem? 53 of 99 Page 5 of 9

6 5. Describe the assembly constraints that are needed to adequately constrain the parts in the two assemblies (5.1 & 5.2) shown below. In your description, reference the numbered surfaces to describe how the constraints would be applied between corresponding parts. List the Degrees of Freedom (DOF), if any, that remain on Part A based on the constraints applied. Assume that Part B in each problem is the grounded part. 5.1 Roller Bearing and Axle assembly [3 POINTS 1 point for correctly identifying the constraint, 2 points for identifying the remaining degrees of freedom] 5.2 Plate with Counterbored Hole and Machine Screw Note: surface C and surface D must be parallel. [3 POINTS 2 points for correctly identifying the constraints, 1 point for identifying the remaining degrees of freedom] 54 of 99 Page 6 of 9

7 6. Use the Answer Bank to fill in the missing steps of the design process by matching the letter that corresponds to the missing step. Record your responses on the answer sheet provided. [6 POINTS 1 point each] Phase 1: Phase 2: Phase 3: Phase 4: Phase 5: Phase 6: Phase 7: 6.1 Identify areas of need or want through market research. Compose a formalized design brief stating the problem that needs to be solved. Identify all constraints that affect the design and classify the constraints within the various resources available. Conceptualization 6.2 Refinement of Preliminary Ideas Compare alternatives and specifications. Create a decision matrix to compare the attributes of the various design solutions and analyze trade-offs. Generate alternative solutions that better satisfy the design criteria. Narrow the available solutions and select a final design. 6.5 Detailed documentation of final design is created. Prototyping is done. Testing and analysis are completed. Optimization 6.6 Presentation Several forms of reporting may be used to adequately express the design solution to any and all parties involved. Answer Bank: A. Reassess the design specifications. Implement any modifications that might be necessary. Update drawings. B. Development and Implementation C. Workable solutions are identified. Detailed/annotated sketches are developed. D. Design Analysis E. Brainstorming occurs and ideas are collected and/or recorded, often in graph form. Research is completed. Thumbnail sketches of ideas are drawn. F. Problem Identification 55 of 99 Page 7 of 9

8 7. Use the drawing of the Table Plate below to answer the following questions. [5 POINTS 1 point each] Table Plate 7.1 What is the diameter of the Table Plate? 7.2 If the center hole on the Table Plate was made with a 9/32 diameter drill bit, would the resulting hole be within tolerance? 7.3 How deep is the Table Plate s center hole? 7.4 What is the overall height of the Table Plate? 7.5 What is the angle of the chamfer that occurs on the top edge of the Table Plate? 56 of 99 Page 8 of 9

9 8. Examine the technical drawing below. The top, front and right side orthographic views are incomplete. Draw the 9 missing lines to complete the three orthographic views. Note: no centerlines or center marks are used in the drawing. [9 POINTS 1 point each] 57 of 99 Page 9 of 9

10 IED Final Exam Spring 2007 Part C Recording Sheet Student Name: Part C Total Score /50 1. [6 points 1 point correct line type; 1 point for correct purpose] Score #1 (Teacher use only) 1.1 Line type: Use: 1.2 Line type: Use: 1.3 Line type: Use: 2. [4 points 1 point each] 2.1 Volume = 2.2 Mass = 2.3 Surface Area = 2.4 Amount of stain = Score #2 (Teacher use only) 3. [9 points 1 point each] 3.1a 3.1b 3.2a 3.2b 3.3a 3.3b 3.3c 3.4a 3.4b Score #3 (Teacher use only) 4. [5 points 1 point each] Score #4 (Teacher use only) 6. [6 points 1 point each] Score #6 (Teacher use only) 7. [5 points 1 point each] Score #7 (Teacher use only) 8. [9 points 1 point each line] Record answers directly on the orthographic drawing on Page 9. Score #8 (Teacher use only) 5. [6 points total] Score #5 (Teacher use only) 5.1 [3 points total 1 point for constraint, 2 points for DOF] Constraint/s: DOF: 5.2 [3 points total 2 points for constraints, 1 point for DOF] Constraint/s: 58 of 99 DOF: Page 1