Reversing Steering

bszikszai
bszikszai Altair Community Member
edited October 2020 in Community Q&A

Hi,

 

Hoping this one will be easy to solve. 

I've set up a full car model for dynamic analysis but we are using a forward mounted steering rack. The steering is currently in reverse because I started with the wizard model that has the steering rack configured behind the front axles. 

How can I reverse the steering action? Is this a coupler feature?

Answers

  • Chris Coker_21312
    Chris Coker_21312 New Altair Community Member
    edited January 2020

    Hi-

    You are correct.  Simply change the sign on the coupler in the steering rack.

     

    Usually, engineers will build separate half-car models first, and verify that the models are running correctly before assembling a full vehicle model.  It's much easier to catch modeling errors like this.

     

    Also, if you modified the steering hard points, it's likely the value of the coupler will also need to change (and not just the sign).  The overall steering ratio needs to be set for the vehicle.

     

    Chris

  • bszikszai
    bszikszai Altair Community Member
    edited January 2020

    Thanks for the quick reply Chris, I've already done the front and rear kinematics and set up the steering separately but didn't catch the reversal until trying to run the dynamic sims. 

    Cheers

    B

     

  • bszikszai
    bszikszai Altair Community Member
    edited January 2020

    I couldnt get it working initially but realised that the sign on the coupler ratio needs to be changed in each simulation task as well as the model. Its working as expected now.

     

    Thanks

    B

  • Chris Coker_21312
    Chris Coker_21312 New Altair Community Member
    edited January 2020

    you should not have to change the sign on the coupler ratio on each simulation task, unless you are running a closed look event (like a lane change), and NOT using the advanced driver.  Even then, the sign should not matter, but the overall magnitude is used for the bicycle model inside the controller.  If you are doing this with the 'Altair driver' then the ratio (for the driver model) is taken are of automatically.

     

    FYI, if you run a front suspension event (like K&C) that steers the wheels, and you see the steering wheel steer to the left, but the road wheels steering to the right, then that's how you identify a need to change the coupler sign.

     

    Can you provide more information about which wizard library you are using?

     

    Best,

    Chris