Error during scaling problem

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1

Good morning,

May God bless you a good health and wealth.

I encountered a problem of simulating a seated model.
I used local anthropometric scaling to analyse the seated model.
However, it produce errors.
The errors are as follows e.g.:

Constraint no. 78 above error tolerance 0.000001, error = 0.000144. - constr. #0 in ‘Main.HumanModel.BodyModel.Trunk.Buckle.Disc1.Disc.LinDrvLeft’
Constraint no. 85 above error tolerance 0.000001, error = 0.000136. - constr. #0 in ‘Main.HumanModel.BodyModel.Trunk.Buckle.Disc1.Disc.drv’
Constraint no. 86 above error tolerance 0.000001, error = 0.000022. - constr. #0 in ‘Main.HumanModel.BodyModel.Trunk.Buckle.Disc2.Jnt.Constraints’
Constraint no. 87 above error tolerance 0.000001, error = 0.000062. - constr. #1 in ‘Main.HumanModel.BodyModel.Trunk.Buckle.Disc2.Jnt.Constraints’

Can anybody provide me a few tips and technique for solving this problem?
I am really appreciate any reply from members in this forum.

Thank You.

2

This post seems to be identical to a previous post which has been answered, if this is not the case please repost it.

The error can not be reproduced.

Please verify that the body model was not altered, this could explain it

Best regards
Søren

3

Good evening,

May God bless you a good health and wealth.

Thank you for the reply.

For your information, I adjusted the value for mass and height for the model. But when I changed the value below 180 cm, the model seem to have errors when I do the analysis.

However, when i changed the value more than 180cm, I can do the analysis without any problem.

Why the errors occur? Is the any relation with the ratio of the segment length?

I hope any member from this forum can help me to solve this problem. I am really appreciate any reply from members in this forum.

Thank you.

4

Hi,

Because Søren is out of office these days so I answer instead of him.

  1. I would recommend you to use ‘uniform scaling’ scheme for your purpose. You can use these following two lines of code:
#define BM_SCALING CONST_SCALING_UNIFORM
...
#path BM_SCALING_ANTHRO_FILE "Model\AnyFamily\AnyManUniform.any"
...

Then you can change the mass and the height of the subject in your AnyManUniform.any file.

  1. The biggest reason why you model may fail during the kinematics analysis when human’s height is less that 180cm may be that the leg becomes shorter than before. So I would rather to adjust a parameter of the chair for shorter legs:
  AnyFolder DrvPos = {
    AnyVar PelvisSeatLinXPos = 0.05;      ///< Position of the pelvis on the seat
    AnyVar SeatGlobalLinYPos = 0;         ///< Seat Height
    AnyVar SeatGlobalZRot = 0;            ///< Forward seat inclination
    AnyVar BackRestHeadResRotZPos = 0;    ///< Rotation of the head rest wrt the back rest
    AnyVar GlobalLegRestRotZPos = 30;     ///< Inclination of the leg rest
    AnyVar GlobalBackRestRotZPos = 0;    ///< Back rest inclination
    AnyVar [b]LegRestFootRestLinYPos [/b]= 0.1 + 0.1 + 0.05 ; ///< Position of the footrest along the leg rest
  }; // DrvPos

Attached please find a modified version of your model which includes all the changes that I mentioned above.

Best regards,
Moonki

5

hi,

Thank you for the help.

So far, I can run the analysis for the human model without any problem.

Thank you for sharing the knowledge with me.