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 Forces In a Suspension Post Reply Forum
 Posted by: himes19 ® 03/30/2006, 12:21:14 Author Profile eMail author Edit I am desingning a suspension. I know lots about mechanical engineering and desing but i just cant find how to calculate the forces when the tires impacts a bump. I would apreciate any help. j.h.

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 Re: Forces In a Suspension Re: Forces In a Suspension -- himes19 Post Reply Top of thread Forum
 Posted by: zekeman ® 03/31/2006, 16:24:28 Author Profile eMail author Edit Depends on the bump you postulate, or hole. Then you can write dynamic equations for the mutidegree of freedom system.

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 Re: Forces In a Suspension Re: Re: Forces In a Suspension -- zekeman Post Reply Top of thread Forum
Posted by: rfox71 ®

04/04/2006, 11:19:43

Author Profile eMail author Edit

Hey,

I pulled this model from my systems book:
Introduction to Dynamic Systems Analysis, T.D. Burton
McGraw-Hill 1994. Its a fairly simplified model but addresses the concepts I believe you were curious about.

Robert

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 Re: Forces In a Suspension Re: Re: Forces In a Suspension -- rfox71 Post Reply Top of thread Forum
 Posted by: zekeman ® 04/05/2006, 20:36:47 Author Profile eMail author Edit Good, thats the model. Now what you have to do is write the 4 diff equations and postulate some reasonanle bump, say f(x)=sin(x)(with limits) on the front wheels and f(x+xo) on the rear tires which you get on the front wheels. Now assume some forward velocity, say v, then the forcing motion at the tires are F=f(vt) and F=f(vt+xo) dF/dt=f'(vt) and dF/dt+f,(vt+xo) on the front and back tires. Now solve this using some canned computer program like SPICE.

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 Re: Forces In a Suspension Re: Re: Forces In a Suspension -- zekeman Post Reply Top of thread Forum
 Posted by: zekeman ® 04/05/2006, 20:48:07 Author Profile eMail author Edit Correction. The velocity equations should read: dF/dt=v*f'(vt)and dF/dt=v*f'(vt+xo) for the front and rear tires .