//Small example showing how to add "rotational spring" in a joint using an interpolation function and an AnyForce object
Main = {
  
  AnyFolder Model={
    
    // Global Reference Frame
    AnyFixedRefFrame GlobalRef = {   };  // Global reference frame
    
    AnySeg Arm={
      Mass=10;
      Jii={0.1,0.1,0.1};
      AnyRefNode node1={sRel={-0.5,0,0};};
      AnyRefNode node2={sRel={0.5,0,0};};
      AnyDrawSeg drw={};
    };
    
    AnySphericalJoint Jnt = {
      AnyRefFrame &L2Node = .GlobalRef;
      AnyRefNode &L1Node = .Arm.node1;
    };
    
    AnyKinEqSimpleDriver driver={
      AnySphericalJoint &jnt =.Jnt;
      DriverPos={0,0,0};
      DriverVel={20,-20,20}*pi/180;
    };
    
    //some stiffness function dependent on angle values
    AnyFunInterpol Stiffness1={
      T={-20,-10,0,10,20}*pi/180; //Angle values
      Data={{10,5,0,-5,-10}}; //some moment values
      Type=Bspline;
    };
    
    
    //adding this stiffness to the joints
    AnyForce spring={
      AnySphericalJoint &ref1=.Jnt;
      F = {.Stiffness1(ref1.Pos[0])[0], .Stiffness1(ref1.Pos[1])[0], .Stiffness1(ref1.Pos[2])[0] };
    };
    
  }; // MyModel

  
  // The study: Operations to be performed on the model
  AnyBodyStudy MyStudy = {
    AnyFolder &Model = .Model;
    RecruitmentSolver = MinMaxSimplex;
    Gravity = {0.0, -9.81, 0.0};
  };
  
};  // Main