Machine Design P2.pdf - 1 Use MATLAB \u201cfminsearch\u201d to design a helical compression spring for a coil-over shock absorber in a small unmanned ground

# Machine Design P2.pdf - 1 Use MATLAB u201cfminsearchu201d...

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1) Use MATLAB “fminsearch” to design a helical compression spring for a coil-over shock absorber in a small unmanned ground vehicle (UGV) based on the following specifications. You must attach hard copy of your code and MATLAB output. minimum weight must fit over 0.57 inch DIA shock body minimum working force Fw= 15 lbf at working length Lw= 1.5 inch minimum factor of safety NFSof 1.0 to prevent static yield at shut length Ls(fully compressed) free length Lf= 3.0 inch, total number of coils Nt= 14 round steel music wire or round zinc-plated steel music wire squared (closed) ends or squared-and-ground ends Current design – Nt= 14, Lf= 3.0 in, OD = 0.80 in, d = 0.081 in, w = 0.046 lbf, NFS= 1.30 2) Select a spring that most closely matches your optimal design from McMaster-Carr. Optimal design McMaster-Carr wire diameter d [in] ____________________ ____________________ coil OD [in] ____________________ ____________________ total number of coils Nt14 ____________________ free length Lf[in] 3.0 ____________________ weight [lbf] ____________________ ____________________ coil ID [in] ____________________ ____________________ spring rate k [lbf/in] ____________________ ____________________ force at Lw[lbf] ____________________