Calculation of roll coefficient on tangent track

Program QUASI in the GENSYS package can be used when calculating the roll coefficient of the carbody. In order to make the calculation the input data file has to be prepared in the following way.

Set constraints to the wheelsets, in order to put the vehicle in a tilted position. Example:

                                        
  constr fix_rigid_1 axl_111  x 0.000   
  constr fix_rigid_1 axl_112  x 0.000   
  constr fix_rigid_1 axl_121  x 0.000   
  constr fix_rigid_1 axl_122  x 0.000   
  constr fix_rigid_1 axl_111  y 0.000   
  constr fix_rigid_1 axl_112  y 0.000   
  constr fix_rigid_1 axl_121  y 0.000   
  constr fix_rigid_1 axl_122  y 0.000   
  constr fix_rigid_1 axl_111  z 0.000   
  constr fix_rigid_1 axl_112  z 0.000   
  constr fix_rigid_1 axl_121  z 0.000   
  constr fix_rigid_1 axl_122  z 0.000   
  constr fix_rigid_1 axl_111  f 0.001   
  constr fix_rigid_1 axl_112  f 0.001   
  constr fix_rigid_1 axl_121  f 0.001   
  constr fix_rigid_1 axl_122  f 0.001   
  constr fix_rigid_1 axl_111  p 0.000   
  constr fix_rigid_1 axl_112  p 0.000   
  constr fix_rigid_1 axl_121  p 0.000   
  constr fix_rigid_1 axl_122  p 0.000

Perform a quasistatic analysis in program QUASI.

The results can be obtained by checking the *.gp-file by the program CATA_GP.
Example: A printout from the CATA_GP program (The information has been selected in order to reduce the amount of data in this paper).

                                                                                
 Start  of  program  CATA_GP rel.9703                                           
 ====================================                                           
                                                                                
 ident   =  qroll                                                               
                                                                                
 head    =  Example of a Bobo-vehicle running at a speed of = 160. (km/h)       
            Wheel/rail geometry function cylindrical  friction= .000            
            Ideal track geom=Tangent_Track; Track irregularities=ideal          
            Calculation of roll-coefficient                                     
                                                                                
 date    =  1997-09-24                                                          
                                                                                
  freedom                     value                                             
 car_1.x                    0.00000E+00                                         
 car_1.y                    1.51493E-03                                         
 car_1.z                   -7.37960E-07                                         
 car_1.f                    1.10006E-03                                         
 car_1.k                    0.00000E+00                                         
 car_1.p                    0.00000E+00                                         
 bog_11.x                   0.00000E+00                                         
 bog_11.y                   5.00033E-05                                         
 bog_11.z                   0.00000E+00                                         
 bog_11.f                   1.04707E-03                                         
 bog_11.k                   2.38676E-08                                         
 bog_11.p                   0.00000E+00                                         
 bog_12.x                   0.00000E+00                                         
 bog_12.y                   5.00033E-05                                         
 bog_12.z                   0.00000E+00                                         
 bog_12.f                   1.04707E-03                                         
 bog_12.k                  -2.38625E-08                                         
 bog_12.p                   0.00000E+00                                         
                                                                                
 EOF has been read                                                              
                                                                                
  End    of  program  CATA_GP                                                   
  ===========================

The roll coefficient for a tilted vehicle on tangent track can be calculated according to the following formula:
```
                                
  C_phi = phi_ks / phi_s - 1.   
                                
```
Where:
   C_phi = The roll coefficient
   phi_ks= The roll angle of the carbody (car_1.f in the above example)
   phi_s = The roll angle of the axles (0.001 in the above example)