Recent content by hutch325

Yes, that makes sense.

Okay so on a tangent, what tire construction and performance characteristics seem to work well on a "high front caster, high KPI, RWD, leading steering car"? That configuration describes just about every BMW. Except depending on model, some have more compliance understeer built into the steering...

I'm assuming in your view the Fy response is more critical to feel than Mz since the Fy response of the Conti at 3.0 bar is relatively quick, while the Mz response seems to be in line with the rest of the pack?

Duh. Thanks, my brain definitely was oatmeal. Got any other Ps and Qs for comparison?

Cibachrome, can you give me a nudge in the right direction with regards to your Ps and Qs? A hint as to what system these transfer functions drop into? Sorry I'm slow to catch on but a long day of Matlab today has turned by brain into oatmeal.

Yeah, I agree that spreadsheets are nearly impossible to check. I tried to make one that would model the 3D kinematics but I gave up and started over in Matlab. A couple things you could do: - make your calculations done in a macro instead of in formulas embedded in the cells - name your...

Yes, I agree with Greg. ESC is a brake-based system. Perhaps you're thinking of some other active handling systems like active anti-roll bars or active steering. ESC is nice because it can reduce vehicle speed automatically or change the vehicle trajectory to mitigate a rollover, and can induce...

Thanks, cibachrome. I've done the fixed steer test many times so I already have the necessary Matlab functions. I just usually use different instruments than the VBox. So what was your method for coming up with the wheelbase of a boat?

VBox and a parking lot. After I posted my response, it clicked with me that I didn't need to measure steering angle if I used the constant steering method. I do have access to a VB20SL that could provide some very interesting data. And yes, I see your point about the understeer gradient only...

Thanks, cibachrome. Excellent information. I agree with "...to all others, bring some data..." I have real problems getting accurate subjective assessments from test drivers (meaning their assessments usually don't agree with the data). Unfortunately, there's no way I'm going to set up the DAQ...

Oops, I accidentally posted this in the wrong forum. Relocate maybe?

I do a fair amount of vehicle testing on the commercial vehicle side of things, and along with that comes lots of rental cars used for travel to the test facility. Lately I've noticed that it seems like modern passenger cars don't have much understeer, at least not as much as I would expect. In...

Thanks, Billy. I take it there are no other comments? I should have time to work on it while the turkey cooks in a couple days.

I'm looking to analyze the suspension of a vehicle that is essentially SLA front and rear, on a force based basis. The goal is to determine lateral load transfer as a function of lateral acceleration, accounting for changing installation ratios, nonlinear spring rates (springs in series, in...

Thanks, that thread was pretty interesting and the effects of using thin vs. thick seemed to make sense. With regards to dyno testing, it seems like you could use a shock dyno that is essentially a linear servo to generate more useful data (i.e. feed it a waveform then measure the resulting...