diff --git a/sources/reactphysics3d/constraint/Contact.cpp b/sources/reactphysics3d/constraint/Contact.cpp
index 1477d5dc..903f47e7 100644
--- a/sources/reactphysics3d/constraint/Contact.cpp
+++ b/sources/reactphysics3d/constraint/Contact.cpp
@@ -29,6 +29,13 @@ using namespace reactphysics3d;
 // Constructor
 Contact::Contact(Body* const body1, Body* const body2, const Vector3D& normal, double penetrationDepth, const Vector3D& point)
                  :Constraint(body1, body2, 2, true), normal(normal), penetrationDepth(penetrationDepth), point(point) {
+    body1Jacobian.changeSize(1,6);
+    body2Jacobian.changeSize(1,6);
+    auxJacobian.changeSize(nbAuxConstraints, 12);
+    auxLowerBounds.changeSize(nbAuxConstraints);
+    auxUpperBounds.changeSize(nbAuxConstraints);
+    auxErrorValues.changeSize(nbAuxConstraints);
+
     body1Jacobian = Matrix(1, 6);
     body2Jacobian = Matrix(1, 6);
     auxJacobian = Matrix(nbAuxConstraints, 12);
diff --git a/sources/reactphysics3d/engine/PhysicsEngine.cpp b/sources/reactphysics3d/engine/PhysicsEngine.cpp
index c87b4682..22445aec 100644
--- a/sources/reactphysics3d/engine/PhysicsEngine.cpp
+++ b/sources/reactphysics3d/engine/PhysicsEngine.cpp
@@ -86,10 +86,8 @@ void PhysicsEngine::updateCollision() {
 
     // While the time accumulator is not empty
     while(timer.getAccumulator() >= timer.getTimeStep().getValue()) {
-
         // Compute the collision detection
         if (collisionDetection.computeCollisionDetection()) {
-
             // TODO : Delete this ----------------------------------------------------------
             for (std::vector<Constraint*>::iterator it = world->getConstraintsBeginIterator(); it != world->getConstraintsEndIterator(); ++it) {
                 RigidBody* rigidBody1 = dynamic_cast<RigidBody*>((*it)->getBody1());
diff --git a/sources/reactphysics3d/mathematics/Matrix.cpp b/sources/reactphysics3d/mathematics/Matrix.cpp
index 61219923..bb0e4938 100644
--- a/sources/reactphysics3d/mathematics/Matrix.cpp
+++ b/sources/reactphysics3d/mathematics/Matrix.cpp
@@ -27,7 +27,7 @@ using namespace reactphysics3d;
 // Constructor without argument
 Matrix::Matrix()
        :nbRow(0), nbColumn(0) {
-
+    array = 0;
 }
 
 // Constructor of the class Matrix
@@ -123,6 +123,28 @@ Matrix::~Matrix() {
     delete this->array;
 }
 
+void Matrix::changeSize(uint newNbRows, uint newNbColumns) {
+    if (array) {
+        // Destruction of the dynamic array
+        for(int i=0; i<nbRow; ++i) {
+            delete array[i];
+        }
+        delete this->array;
+    }
+
+    // Create the two dimensional dynamic array
+    array = new double*[newNbRows];
+
+    assert(array != 0);     // Array pointer musn't be null
+
+    for(int i=0; i<newNbRows; ++i) {
+        array[i] = new double[newNbColumns];
+    }
+
+    nbColumn = newNbColumns;
+    nbRow = newNbRows;
+}
+
 
 // Function that return the cofactor matrix by removing row i and column j
 Matrix Matrix::getCofactor(int i, int j) const throw(std::invalid_argument) {
diff --git a/sources/reactphysics3d/mathematics/Matrix.h b/sources/reactphysics3d/mathematics/Matrix.h
index 3c28cf4d..690e4bed 100644
--- a/sources/reactphysics3d/mathematics/Matrix.h
+++ b/sources/reactphysics3d/mathematics/Matrix.h
@@ -66,6 +66,7 @@ class Matrix {
         void fillInSubMatrix(unsigned int i, unsigned int j, const Matrix& subMatrix);                                  // Fill in a sub-matrix of the current matrix with another matrix
         void initWithValue(double value);                                                                               // Initialize all the matrix with the given value
         void display() const;                                                                                           // TO DELETE
+        void changeSize(uint nbRows, uint nbColumns);
 
         // --- Overloaded operators --- //
         Matrix operator+(const Matrix& matrix2) const throw(MathematicsException);                                      // Overloaded operator for addition
diff --git a/sources/reactphysics3d/mathematics/Vector.cpp b/sources/reactphysics3d/mathematics/Vector.cpp
index 32154a1c..319d1273 100644
--- a/sources/reactphysics3d/mathematics/Vector.cpp
+++ b/sources/reactphysics3d/mathematics/Vector.cpp
@@ -26,7 +26,7 @@ using namespace reactphysics3d;
 // Constructor without argument
 Vector::Vector()
        :nbComponent(0) {
-
+    tab = 0;
 }
 
 // Constructor of the class Vector
@@ -148,6 +148,20 @@ Vector Vector::crossProduct(const Vector& vector) const throw(MathematicsExcepti
     }
 }
 
+void Vector::changeSize(uint newSize) {
+    if (tab) {
+         delete[] tab;
+    }
+
+    nbComponent = newSize;
+    tab = new double[nbComponent];
+
+    // Fill the array with the value of the vector
+    for (int i=0; i<nbComponent; ++i) {
+        tab[i] = 0.0;
+    }
+}
+
 // Overloaded operator for addition
 Vector Vector::operator+(const Vector& vector) const throw(MathematicsException) {
     // Check the size of the two vectors
diff --git a/sources/reactphysics3d/mathematics/Vector.h b/sources/reactphysics3d/mathematics/Vector.h
index d4948767..8e5fbcc0 100644
--- a/sources/reactphysics3d/mathematics/Vector.h
+++ b/sources/reactphysics3d/mathematics/Vector.h
@@ -164,17 +164,6 @@ inline Vector operator*(double number, const Vector& vector) {
     return vector * number;
 }
 
-void Vector::changeSize(uint newSize) {
-    delete[] tab;
-    nbComponent = newSize;
-    tab = new double[nbComponent];
-
-    // Fill the array with the value of the vector
-    for (int i=0; i<nbComponent; ++i) {
-        tab[i] = 0.0;
-    }
-}
-
 } // End of the ReactPhysics3D namespace
 
 #endif
diff --git a/sources/reactphysics3d/mathematics/lcp/LCPSolver.h b/sources/reactphysics3d/mathematics/lcp/LCPSolver.h
index f343ffbb..df6f8320 100644
--- a/sources/reactphysics3d/mathematics/lcp/LCPSolver.h
+++ b/sources/reactphysics3d/mathematics/lcp/LCPSolver.h
@@ -73,7 +73,7 @@ inline void LCPSolver::setLambdaInit(const Vector& lambdaInit) {
 }
 
 // Set the maximum number of iterations
-void LCPSolver::setMaxIterations(uint maxIterations) {
+inline void LCPSolver::setMaxIterations(uint maxIterations) {
     assert(maxIterations > 0);
     this->maxIterations = maxIterations;
 }