Design Project: Hand Truck
Problem
Design a lightweight, low-cost hand truck that converts simply into a platform truck (see concept sketch). In platform mode the structure need not have a handle. In either mode, the truck must carry a 300 lb load distributed over either the entire nose plate or the full width of the platform and the length h between the wheel axles. Key specifications: * Variable height (H) handle ranging from 40 to 50 in. * Minimum length h will be 28 in. * Width of the load-bearing surfaces (noseplate and platform) will be 20 in. * Nose plate will extend no less than 10 in. * Design for mild impact: Assume the 300 lb load drops from a height of zero above the truck (see Hibbeler (1997), § 14.4, Eq. 14.34 in particular). * As a precaution against material yielding, set the factor of safety (FS) to 1.3. * Select wheels with rubber-like tires to prevent marring floors, yet prevent slipping. The upper set of wheels must swivel to permit turning in cart mode.

Design Objective
The design objectives are light weight and minimum cost in that order. Hence a figure of merit equal to the weight of the truck in pounds multiplied by the cost in dollars is to be reported. Costs are to be determined using nominal retail prices.
Special Concerns * Adjustment of the handle height should be simple, safe and easy to do. * The nose plate should not mar the floor when the truck is resting upright

Design Report
The design will be done in U.S. Customary Units. Follow instructions in “The Design Report Format”.
References
1. Design in Strength of Materials web site http://www.esm.psu.edu/courses/emch213d/ 2. Hibbeler, R.C. (1997) Mechanics of Materials, Prentice Hall, Englewood Cliffs. 3. Roark, Raymond J. and W. C. Young (1975) Formulas for Stress and Strain, McGraw-Hill Book Co., New York, Table 37. Formulas of stress concentration for elastic stress.
Project Submittals * DP1 , Conceptual Design – submit dimensioned sketches showing the layout of the design; components do NOT need to be sized; identify the components and connections that will be designed – Due Nov. 11 * DP2, Material Selection – identify the materials to be used in the design; list the relevant materials properties; provide a rationale for your selections – Due Nov. 11 * DP3, Load Specifications – state the load specifications that will be used in the design and provide justification for these values; identify the applicable standards – Due Nov. 16 * DP4, Design Analysis – submit the complete design analysis including assumptions, warnings, calculations, and design sketches – Due Nov. 30 * DP5, Calculations Check – provide a check of calculations prepared by another team; comment on assumptions, underlying ideas, applicability of formulas used, as well as correctness of sample computations – Due Nov. 30 * DP6, Drawings – prepare design drawings of the gym set of the quality necessary for fabrication – Due Nov. 7 * DP7, Cost Estimate – estimate the cost of the gym set; document sources of prices – Due Nov. 7 * DP8, Design Report – organize and format the submittals DP1-DP7 into a professional quality report – Due Dec 14.