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adriannunes

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About adriannunes

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  1. I am using the following as the tire property file from examples and also other examples of road property file from examples ! HWVERSION_2019.1.0.20_Jun 28 2019_20:45:2 $----------------------------------------------------------------units [UNITS] LENGTH ='meter' FORCE ='newton' ANGLE ='radians' MASS ='kg' TIME ='second' $--------------------------------------------------------------------------model [MODEL] PROPERTY_FILE_FORMAT = 'USER' FUNCTION_NAME = 'mbdtire::USER_FIALA' USE_MODE = 1 CONTACT_MODEL = '3D_ENVELOPING' $-----------------------------------------------------------dimensions [DIMENSION] UNLOADED_RADIUS = 0.272 $Free tyre radius WIDTH = 0.177 $Nominal section width of the tyre ASPECT_RATIO = 0.6 $Nominal aspect ratio $----------------------------------------------------------------------parameter [PARAMETER] VERTICAL_STIFFNESS = 47651.8 $Vertical Stiffness [force/length] VERTICAL_DAMPING = 50 $Vertical Damping [force * time / length] ROLLING_RESISTANCE = 0.007 $Rolling Resistance Moment Coefficient [length] CSLIP = 86748 $Logitudinal Slip Stiffness [force]; CALPHA = 61296 $Cornering Stiffness [force / angle] CGAMMA = 3594 $Camber Stiffness [force / angle] UMAX = 1.0 $Static Friction Coefficient UMIN = 0.878 $Sliding Friction Coefficient RLENX = 0.242 $Relaxation Length in x direction RLENY = 0.597 $Relaxation Length in y direction ROLLING_RADIUS_FACTOR = 0.5 $Rolling radius = loaded radius + ROLLING_RADIUS_FACTOR *(unloaded radius - loaded radius) $--------------------------------------------------------contact_patch [CONTACT_COEFFICIENTS] PA1 = 0.671 $Coefficient of square root term in contact length equation PA2 = 0.733 $Coefficient of linear term in contact length equation PB1 = 1.059 $Coefficient of cube root term in contact width equation PB2 = -1.1878 $Coefficient of linear term in contact width equation PLS = 0.8335 $Scaling of distance between front and rear ellipsoid PAE = 0.4382 $Half of ellipsoid length PBE = 0.302 $Half of Ellipsoid height PCE = 1.5174 $Order of ellipsoid ROAD_INCREMENT = 0.001 $distance between contact points N_WIDTH = 4 $Number of cams along contact width N_LENGTH = 4 $Number of cams along contact length and also used the road property file that you have mentioned as above and did the following rotations also. I have checked the .log file and it shows that it has taken the pot hole profile and FIALA tire too. but still I can't simulate it going through the pot hole or any cleat. 2. The left side half shaft and output shaft remains straight but only the right side deforms. The axis of rotation of half shaft and wheel center is not the same. Had changed the position according to our geometry. Thank you
  2. 1. I have started using FIALA Tire model and given RDF files in the FIALA file, I have used different USE MODE code (0,1,2,434,534) for the Simulations but the pothole is still not being simulated it follows a straight line. 2. While the vehicle moving forward the output shaft and the half shaft on the right side are not straight and tend to deform and form an angle like its buckling.
  3. 1. The USE_MODE value is 114. I tried the values as 434 and 400 also, but encountered licencing error from --- TASS Licensing Service ---. 2. I have checked for the orientation of the Road Reference Marker it matches with my geometric axis, But they are at different heights. Is it alright to keep it unchanged. 3. I am also using the TNO_plank_road RDF file as the Road Property File. Will this work? 4.According to the USE_MODE code I want to evaluate the forces in Fz direction also, only Fx, Fy and Mx My Mz is specified. Thank You
  4. Thank You Chris I am using the Auto-Tires FILE_TYPE ='tir' FILE_VERSION =3.0 FILE_FORMAT ='ASCII' ! ! FILE_NAME : TNO_car205_60R15.tir ! TIRE_VERSION : MF-Tyre/MF-Swift 6.2 ! MF-TOOL TEMPLATE : TNO_mfswift62 $Revision: 1.15 $ From the tire property file I tried using the TNO_Plank .RDF file but still the vehicle in the H3D model shows no simulation of going over the Plank it follows the straight path only. (It is the original file in the library) Can you please provide your secure dropbox ID.
  5. Thank you 1.) I tried simulating it, but it still continued to be a straight path only. I have edited the file as the following Road Type = 2D FLAT $---------------------------------------------------------------------ALTAIR_HEADER [ALTAIR_HEADER] FILE_TYPE = 'rdf' FILE_VERSION = 5.00 FILE_FORMAT = 'ASCII' ! ! road data file for TNO_flat_road ! $--------------------------------------------------------------------------units [UNITS] LENGTH = 'meter' FORCE = 'newton' ANGLE = 'radians' MASS = 'kg' TIME = 'sec' $---------------------------------------------------------------------definition [MODEL] PROPERTY_FILE_FORMAT = 'USER' FUNCTION_NAME = 'mssticsub::ROAD' METHOD = '2D' ROAD_TYPE = 'flat' $---------------------------------------------------------------------parameters [PARAMETERS] OFFSET = 0 ROTATION_ANGLE_XY_PLANE = 180 MU = 1.0 $ DEPTH = -0.05 START = 10 LENGTH =0.5 (I am editing it in notepad and then saving it) Please point out to the mistake. I want to create a pothole of the following dimension on the road. (dimension in meters) 2) I have used the Vehicle Tools to create graphic files for the road files I am using (CRG,RDF) so I get an idea about the road graphically. Is it possible to create a graphic file for the above code or for instance any .RDF or .ADF file given in the directory. How do I do it? 3) How do you add ramps and potholes in .CRG file?
  6. I am using the full vehicle with driver. and have gone through the help files available. To perform various maneuvers I have edited the .adf file for event altairdriverfile, in the .txt format and then inserted it from the event editor tab. For the .adf file I copied a existing .adf file from Altair library (Straight Line Braking) and then added the following from 3D spline road data file available in the help section. $-------------------------------------------------------------------------END_DATA_POINTS [OBSTACLE1] ROAD_TYPE = 'PotHole' COORDINATE_SYSTEM = 'distance' START = 0.7 LENGTH = 1.5 DEPTH = -0.007 $-------------------------------------------------------------------------END_OBSTACLE1 [OBSTACLE2] ROAD_TYPE = 'Curb' HEIGHT = 0.05 START = 0 ROUND_OFF = 3.99805 TOP_WIDTH = 1 EDGE_WIDTH = 3 But it only performed the straight line braking. How do I insert the code for it? ( I want to add a few bumps and drops)
  7. Thank you I have license for FIALA\HTIRE and a few road file in .crg format. 1. Steps to create a condition that would include the vehicle velocity and steering inputs in the analysis to follow the path (I would like to simulate as shown in the attachment & create outputs // Do I need to use Altair Driver) A. Can I generate a Road File in ADAMS\Car and then use the following in MV (How & Can I create my own road file in other softwares) B. How do you change a road definition file to non-flat road.
  8. Thank you, I am a bit confused, So How do I calculate the inertia values? (FYI- I have a CAD model for my car and the following parts. Do I take the MOI values about the CG of the part OR CG of the vehicle) I am trying to read the data using Hyper Graph 2D and using .plt In the Y components and what does f2, f3, f4 so on means.
  9. Thank you 1. I have changed the end time to 15, yet the simulation goes on only for 6 sec. 2. I have entered the values obtained from Tools>CG\Inertia Summary>Moment of inertia into Model>Data Summary>Bodies and getting this error. Also does adding these values lead to more accurate results? STATICS SIMULATION COMPLETED Deactivate MOTION/115002 Deactivate MOTION/215002 Deactivate MOTION/115003 Deactivate MOTION/215003 Deactivate JPRIM/303001 Deactivate JPRIM/303002 Execute Modify Command... ORIGINAL: <Motion_Joint id="315001" expr="0"/> MODIFIED: <Motion_Joint id="315001" expr="VARVAL(31500100)"/> INFO: Starting SMP run with up to 4 threads. WARNING: Error in principal J for body [id=10505]: Ji+Jj<Jk! J=(2746.05, 254064, 280604) in body CG principal inertia frame. Execution continues but the results, if dynamic analysis, may be incorrect! WARNING: Error in principal J for body [id=20505]: Ji+Jj<Jk! J=(2746.05, 254064, 280604) in body CG principal inertia frame. Execution continues but the results, if dynamic analysis, may be incorrect! WARNING: Error in principal J for body [id=11405]: Ji+Jj<Jk! J=(10487.3, 455235, 584910) in body CG principal inertia frame. Execution continues but the results, if dynamic analysis, may be incorrect! WARNING: Error in principal J for body [id=21405]: Ji+Jj<Jk! J=(10487.3, 455235, 584910) in body CG principal inertia frame. Execution continues but the results, if dynamic analysis, may be incorrect! Calling RELSUB in DLL [mbdtire]... INFO: Analysis model processed. Partitioning generalized coordinates... INFO: Total Number of Independent Coordinates = 133 Generalized coordinates partitioned. Continue with initializing model... INFO: Number of Total Entries in Residual Vector: 6365 INFO: Number of Non-zero Entries in Jacobian Mtx: 43487 (0.10734% Filled) INFO: Number of Entries Associated with VarCoord: 3094 (7.11477%) Solving Initial Velocity... INFO: Initial velocity solution converged in 2 iterations. Starting dynamic analysis... DYNAMIC SIMULATION PARAMETERS ---------------------------------------- Start Time : 0.000E+00 End Time : 1.957E+01 Print Interval : 2.000E-02 Integrator : DSTIFF Error Tolerance : 1.000E-02 Maximum Step Size : 1.000E-03 Minimum Step Size : 1.000E-10 DAE Index : 3 DAE Constraint Tolerance : 1.000E-05 ++----------------++ Time=3.873E-04; Order=1; H=3.873E-04 [Max Phi=1.147E-07] Time=3.345E-02; Order=3; H=1.000E-03 [Max Phi=1.923E-07] Time=5.875E-02; Order=2; H=2.500E-04 [Max Phi=4.032E-06] WARNING: [DASPK] The nonlinear system solver in the time integration failed to achieve convergence, and there were repeated error test failures in this step ..... WARNING: EvaluateResidual failed (NaN encountered)! Future warnings will be suppressed. Residual idx=6300, GS/313004 Y6 ERROR: [DASPK] IRES = -2 was encountered and control is being returned to the calling program ..... DAE SOLVER STATISTICS (DASPK-Index3) ------------------------------------------------ Number of solution steps = 92 Number of residue evaluations = 561 Number of jacobian computations = 159 Number of error test failures = 21 Number of nonlinear convergence failures = 25 WARNING: Repeated abnormal return from integrator! ERROR: At time=5.938E-02 the integrator failed to proceed. ----------- Possible Causes ----------------------------------------------------- (1) The integration has become unstable. Tighten (decrease) integr_tol, h_max, or both in Param_Transient can help stabilize the integration. If the simulation contains distinctive phases, use multiple Simulate, each with its own proper integrator parameter setting, to selectively tighten the tolerance during the period where instability is encountered. (2) If the simulation was terminated because stepsize has diminished consistently below h_min, reduce h_min in Param_Transient to force integration to continue. (3) Non-physical inertia properties, such as mass=100 Kg and Ixx=Iyy=Izz=1 Kg*mm^2, or extremely small inertia on a part with an unconstrained degree of freedom. Make sure the modeling data, in particular the part inertia and the gravity, are specified in proper units consistent with the units given in Param_Unit element. (4) Beam, flexible body goes out of linear range, bushing has large rotation along more than one axis, curve goes out of its interpolation range, higher-pair joint goes out of the range of U or V, etc. Make sure fundamental modeling assumptions, such as rigid contact assumption used in Force_Contact, are not violated. (5) Motion displacement defined using LINSPL, AKISPL in dynamic analysis, or as a function of model states (DX, VX etc), as well as forces defined as a function of other forces, can cause hard convergence and integrator failure. Avoid these modeling practices wherever possible. ---------------------------------------------------------------------------------
  10. Thank you, changing the sign for the coupler solved it. 1) While simulating for the single lane change, the car used to not complete the full track according to specified speeds . So I altered the track length by changing the formula in segment distance which is[ 1000*sqrt(ds_lane_chg.lat_span.value^2+ds_lane_chg.long_span.value^2)] to (800*sqrt.....) and (500*sqrt...) which reduced the track length. But then the steering wheel became irresponsive when it enters the lane and later approx while exiting the lane becomes responsive and starts to turn as shown in the attachments. How can I change the time for the simulation which is 6 seconds also the Lateral 0.5G can it be change to a higher value to take sharper lane changes. 2) I wanted to simulate the vehicle going down a slope so I altered the single lane change points (outline points 5,6,7,8). But the vehicle continued to move in the straight line only. shown in the attachments Is it possible to do it this or can any changes be done to make it follow the track or templates be created for such specific events. also can the following load output request be created for it or copying the properties from different output request from other analysis be the solution ? 3) As suggested above for the moment of inertia, the value that are used for computing the analysis are taken from the data summary (where I will have to update it to the values given in CG/Inertia summary ) or from the tool>CG/inertia summary value are taken directly for computing. Which Values do I use and do I update it in the data summary. How do I change the reference frame from global frame.
  11. Thank You I have done the straight line braking analysis with only setting the hard points, mass and the event parameters and default moment of inertia values. But, during the constant radius analysis the car takes a turn in the wrong direction as shown in the below attachments. How do we control the steering inputs, do we need to use advance driver? Which are the input data that affect my results? We are getting values for the MOI from the above instructions given by Chris Coker, can using those values lead to correct results?
  12. How do I calculate the moment of inertia, do we calculate it about the body's origin OR from the CG of the vehicle.
  13. What do you mean by model being robust and correct weight on the wheels? I have also carried out the Static ride and K&C and have got the results. should I carry the same process with the rear and then carry on with the full car assembly?
  14. I have been carrying out the analysis on the full vehicle and have changed the hard points, mass, spring, moment of inertia (taken from Tools>CG\Inertia Summary) and preload values.I got the following errors in the solving process. Which parameter do I need to take care while carrying out the analysis. INFO: Starting SMP run with up to 4 threads. WARNING: Error in principal J for body [id=10306]: Ji+Jj<Jk! J=(500, 500, 10000) in body CG principal inertia frame. Execution continues but the results, if dynamic analysis, may be incorrect! WARNING: Error in principal J for body [id=20306]: Ji+Jj<Jk! J=(500, 500, 10000) in body CG principal inertia frame. Execution continues but the results, if dynamic analysis, may be incorrect! WARNING: Error in principal J for body [id=10307]: Ji+Jj<Jk! J=(100, 100, 1000) in body CG principal inertia frame. Execution continues but the results, if dynamic analysis, may be incorrect! WARNING: Error in principal J for body [id=20307]: Ji+Jj<Jk! J=(100, 100, 1000) in body CG principal inertia frame. Execution continues but the results, if dynamic analysis, may be incorrect!
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