Hello !
I’m trying to solve static mechanics equations, hence implying vectors.
I tried with a simple case but Matlab is unable to find an explicit solution, though it should be solvable. It seems to me as if there is an error in the code preventing Matlab to properly spot the unknowns (which are vector components).
Here’s a minimal code example, with a couple of tries with solve :
syms g mS fS real positive
syms vR_S_1 vR_S_2 vR_S_3 real

vP_S = [0; 0; -mS * g];
vR_S = [vR_S_1; vR_S_2; vR_S_3];

S1 = solve([vP_S + vR_S == zeros(3, 1); vR_S(2)^2 == vR_S(3)^2 * fS^2 – vR_S(1)^2]’, [vR_S(3), vR_S(1)])
S2 = solve([vP_S + vR_S == zeros(3, 1); vR_S_2^2 == vR_S_3^2 * fS^2 – vR_S_1^2]’, [vR_S_3, vR_S_1])
S3 = solve(subs([vP_S + vR_S == zeros(3, 1); vR_S_2^2 == vR_S_3^2 * fS^2 – vR_S_1^2])’, [vR_S_3, vR_S_1])
Any clue about what’s going on ?
Many thanks in advance !Hello !
I’m trying to solve static mechanics equations, hence implying vectors.
I tried with a simple case but Matlab is unable to find an explicit solution, though it should be solvable. It seems to me as if there is an error in the code preventing Matlab to properly spot the unknowns (which are vector components).
Here’s a minimal code example, with a couple of tries with solve :
syms g mS fS real positive
syms vR_S_1 vR_S_2 vR_S_3 real

vP_S = [0; 0; -mS * g];
vR_S = [vR_S_1; vR_S_2; vR_S_3];

S1 = solve([vP_S + vR_S == zeros(3, 1); vR_S(2)^2 == vR_S(3)^2 * fS^2 – vR_S(1)^2]’, [vR_S(3), vR_S(1)])
S2 = solve([vP_S + vR_S == zeros(3, 1); vR_S_2^2 == vR_S_3^2 * fS^2 – vR_S_1^2]’, [vR_S_3, vR_S_1])
S3 = solve(subs([vP_S + vR_S == zeros(3, 1); vR_S_2^2 == vR_S_3^2 * fS^2 – vR_S_1^2])’, [vR_S_3, vR_S_1])
Any clue about what’s going on ?
Many thanks in advance ! Hello !
I’m trying to solve static mechanics equations, hence implying vectors.
I tried with a simple case but Matlab is unable to find an explicit solution, though it should be solvable. It seems to me as if there is an error in the code preventing Matlab to properly spot the unknowns (which are vector components).
Here’s a minimal code example, with a couple of tries with solve :
syms g mS fS real positive
syms vR_S_1 vR_S_2 vR_S_3 real

vP_S = [0; 0; -mS * g];
vR_S = [vR_S_1; vR_S_2; vR_S_3];

S1 = solve([vP_S + vR_S == zeros(3, 1); vR_S(2)^2 == vR_S(3)^2 * fS^2 – vR_S(1)^2]’, [vR_S(3), vR_S(1)])
S2 = solve([vP_S + vR_S == zeros(3, 1); vR_S_2^2 == vR_S_3^2 * fS^2 – vR_S_1^2]’, [vR_S_3, vR_S_1])
S3 = solve(subs([vP_S + vR_S == zeros(3, 1); vR_S_2^2 == vR_S_3^2 * fS^2 – vR_S_1^2])’, [vR_S_3, vR_S_1])
Any clue about what’s going on ?
Many thanks in advance ! solve, vectors, symbolic MATLAB Answers — New Questions

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