Converting trailers to semi trailers

[LEFT]converting trailers to semi trailers .
Is there an body can analysis the forces act on fifth wheel and all the body of the trailer after removing the front axle of it and can ensure the stability of steering
finally there is nothing except sending to you my thanks for reading my problem
please send me any information about this problem

(my e-mail is (ahm_eng_1985@yahoo.com

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