diff --git a/src/body/Body.h b/src/body/Body.h
index dbacc55d..337b9df1 100644
--- a/src/body/Body.h
+++ b/src/body/Body.h
@@ -218,11 +218,14 @@ inline void Body::setIsSleeping(bool isSleeping) {
         }
     }
 
-    mIsSleeping = isSleeping;
+    if (mIsSleeping != isSleeping) {
 
-    RP3D_LOG(mLogger, Logger::Level::Information, Logger::Category::Body,
+        mIsSleeping = isSleeping;
+
+        RP3D_LOG(mLogger, Logger::Level::Information, Logger::Category::Body,
              "Body " + std::to_string(mID) + ": Set isSleeping=" +
              (mIsSleeping ? "true" : "false"));
+    }
 }
 
 // Return a pointer to the user data attached to this body
diff --git a/src/body/CollisionBody.cpp b/src/body/CollisionBody.cpp
index f7e7fe1d..62c035ff 100644
--- a/src/body/CollisionBody.cpp
+++ b/src/body/CollisionBody.cpp
@@ -109,6 +109,10 @@ ProxyShape* CollisionBody::addCollisionShape(CollisionShape* collisionShape,
     RP3D_LOG(mLogger, Logger::Level::Information, Logger::Category::Body,
              "Body " + std::to_string(mID) + ": Proxy shape " + std::to_string(proxyShape->getBroadPhaseId()) + " added to body");
 
+    RP3D_LOG(mLogger, Logger::Level::Information, Logger::Category::ProxyShape,
+             "ProxyShape " + std::to_string(proxyShape->getBroadPhaseId()) + ":  collisionShape=" +
+             proxyShape->getCollisionShape()->to_string());
+
     // Return a pointer to the collision shape
     return proxyShape;
 }
diff --git a/src/body/RigidBody.cpp b/src/body/RigidBody.cpp
index 3791c9d9..4a05010b 100644
--- a/src/body/RigidBody.cpp
+++ b/src/body/RigidBody.cpp
@@ -310,6 +310,10 @@ ProxyShape* RigidBody::addCollisionShape(CollisionShape* collisionShape,
     RP3D_LOG(mLogger, Logger::Level::Information, Logger::Category::Body,
              "Body " + std::to_string(mID) + ": Proxy shape " + std::to_string(proxyShape->getBroadPhaseId()) + " added to body");
 
+    RP3D_LOG(mLogger, Logger::Level::Information, Logger::Category::ProxyShape,
+             "ProxyShape " + std::to_string(proxyShape->getBroadPhaseId()) + ":  collisionShape=" +
+             proxyShape->getCollisionShape()->to_string());
+
     // Return a pointer to the proxy collision shape
     return proxyShape;
 }
diff --git a/src/collision/shapes/BoxShape.h b/src/collision/shapes/BoxShape.h
index b1128582..7e5fba31 100644
--- a/src/collision/shapes/BoxShape.h
+++ b/src/collision/shapes/BoxShape.h
@@ -231,7 +231,7 @@ inline Vector3 BoxShape::getCentroid() const {
 
 // Return the string representation of the shape
 inline std::string BoxShape::to_string() const {
-    return "BoxShape {extents=" + mExtent.to_string() + "}";
+    return "BoxShape{extents=" + mExtent.to_string() + "}";
 }
 
 // Return the number of half-edges of the polyhedron
diff --git a/src/collision/shapes/CapsuleShape.h b/src/collision/shapes/CapsuleShape.h
index decf6474..c595da77 100644
--- a/src/collision/shapes/CapsuleShape.h
+++ b/src/collision/shapes/CapsuleShape.h
@@ -178,7 +178,7 @@ inline Vector3 CapsuleShape::getLocalSupportPointWithoutMargin(const Vector3& di
 
 // Return the string representation of the shape
 inline std::string CapsuleShape::to_string() const {
-    return "CapsuleShape {halfHeight=" + std::to_string(mHalfHeight) + ", radius=" + std::to_string(getRadius()) + "}";
+    return "CapsuleShape{halfHeight=" + std::to_string(mHalfHeight) + ", radius=" + std::to_string(getRadius()) + "}";
 }
 
 }
diff --git a/src/collision/shapes/ConcaveMeshShape.cpp b/src/collision/shapes/ConcaveMeshShape.cpp
index a6cfcb9c..21677154 100644
--- a/src/collision/shapes/ConcaveMeshShape.cpp
+++ b/src/collision/shapes/ConcaveMeshShape.cpp
@@ -221,7 +221,7 @@ std::string ConcaveMeshShape::to_string() const {
 
     std::stringstream ss;
 
-    ss << "ConcaveMeshShape {" << std::endl;
+    ss << "ConcaveMeshShape{" << std::endl;
     ss << "nbSubparts=" << mTriangleMesh->getNbSubparts() << std::endl;
 
     // Vertices array
diff --git a/src/collision/shapes/ConvexMeshShape.cpp b/src/collision/shapes/ConvexMeshShape.cpp
index 3dadfee4..01cb9dc6 100644
--- a/src/collision/shapes/ConvexMeshShape.cpp
+++ b/src/collision/shapes/ConvexMeshShape.cpp
@@ -206,7 +206,7 @@ bool ConvexMeshShape::testPointInside(const Vector3& localPoint, ProxyShape* pro
 std::string ConvexMeshShape::to_string() const {
 
     std::stringstream ss;
-    ss << "ConvexMeshShape {" << std::endl;
+    ss << "ConvexMeshShape{" << std::endl;
     ss << "nbVertices=" << mPolyhedronMesh->getNbVertices() << std::endl;
     ss << "nbFaces=" << mPolyhedronMesh->getNbFaces() << std::endl;
 
diff --git a/src/collision/shapes/HeightFieldShape.cpp b/src/collision/shapes/HeightFieldShape.cpp
index 0136c881..37d73005 100644
--- a/src/collision/shapes/HeightFieldShape.cpp
+++ b/src/collision/shapes/HeightFieldShape.cpp
@@ -303,16 +303,16 @@ std::string HeightFieldShape::to_string() const {
 
     std::stringstream ss;
 
-    ss << "HeightFieldShape {" << std::endl;
+    ss << "HeightFieldShape{" << std::endl;
 
     ss << "nbColumns=" << mNbColumns << std::endl;
-    ss << "nbRows=" << mNbRows << std::endl;
-    ss << "width=" << mWidth << std::endl;
-    ss << "length=" << mLength << std::endl;
-    ss << "minHeight=" << mMinHeight << std::endl;
-    ss << "maxHeight=" << mMaxHeight << std::endl;
-    ss << "upAxis=" << mUpAxis << std::endl;
-    ss << "integerHeightScale=" << mIntegerHeightScale << std::endl;
+    ss << ", nbRows=" << mNbRows << std::endl;
+    ss << ", width=" << mWidth << std::endl;
+    ss << ", length=" << mLength << std::endl;
+    ss << ", minHeight=" << mMinHeight << std::endl;
+    ss << ", maxHeight=" << mMaxHeight << std::endl;
+    ss << ", upAxis=" << mUpAxis << std::endl;
+    ss << ", integerHeightScale=" << mIntegerHeightScale << std::endl;
     ss << "}";
 
     return ss.str();
diff --git a/src/collision/shapes/SphereShape.h b/src/collision/shapes/SphereShape.h
index 01e2001e..baebf6e1 100644
--- a/src/collision/shapes/SphereShape.h
+++ b/src/collision/shapes/SphereShape.h
@@ -175,7 +175,7 @@ inline bool SphereShape::testPointInside(const Vector3& localPoint, ProxyShape*
 
 // Return the string representation of the shape
 inline std::string SphereShape::to_string() const {
-    return "SphereShape { radius=" + std::to_string(getRadius()) + "}";
+    return "SphereShape{radius=" + std::to_string(getRadius()) + "}";
 }
 
 }
diff --git a/src/collision/shapes/TriangleShape.h b/src/collision/shapes/TriangleShape.h
index 23a55c38..87ae5398 100644
--- a/src/collision/shapes/TriangleShape.h
+++ b/src/collision/shapes/TriangleShape.h
@@ -317,7 +317,7 @@ inline void TriangleShape::setRaycastTestType(TriangleRaycastSide testType) {
 
 // Return the string representation of the shape
 inline std::string TriangleShape::to_string() const {
-    return "TriangleShape {v1=" + mPoints[0].to_string() + ", v2=" + mPoints[1].to_string() + "," +
+    return "TriangleShape{v1=" + mPoints[0].to_string() + ", v2=" + mPoints[1].to_string() + "," +
             "v3=" + mPoints[2].to_string() + "}";
 }
 
diff --git a/src/constraint/BallAndSocketJoint.h b/src/constraint/BallAndSocketJoint.h
index ed66320f..33260bfb 100644
--- a/src/constraint/BallAndSocketJoint.h
+++ b/src/constraint/BallAndSocketJoint.h
@@ -133,6 +133,9 @@ class BallAndSocketJoint : public Joint {
         /// Deleted copy-constructor
         BallAndSocketJoint(const BallAndSocketJoint& constraint) = delete;
 
+        /// Return a string representation
+        virtual std::string to_string() const override;
+
         /// Deleted assignment operator
         BallAndSocketJoint& operator=(const BallAndSocketJoint& constraint) = delete;
 };
@@ -142,6 +145,12 @@ inline size_t BallAndSocketJoint::getSizeInBytes() const {
     return sizeof(BallAndSocketJoint);
 }
 
+// Return a string representation
+inline std::string BallAndSocketJoint::to_string() const {
+    return "BallAndSocketJoint{ localAnchorPointBody1=" + mLocalAnchorPointBody1.to_string() +
+            ", localAnchorPointBody2=" + mLocalAnchorPointBody2.to_string() + "}";
+}
+
 }
 
 #endif
diff --git a/src/constraint/FixedJoint.h b/src/constraint/FixedJoint.h
index 45fe1185..bc472cfa 100644
--- a/src/constraint/FixedJoint.h
+++ b/src/constraint/FixedJoint.h
@@ -144,6 +144,9 @@ class FixedJoint : public Joint {
         /// Deleted copy-constructor
         FixedJoint(const FixedJoint& constraint) = delete;
 
+        /// Return a string representation
+        virtual std::string to_string() const override;
+
         /// Deleted assignment operator
         FixedJoint& operator=(const FixedJoint& constraint) = delete;
 };
@@ -153,6 +156,14 @@ inline size_t FixedJoint::getSizeInBytes() const {
     return sizeof(FixedJoint);
 }
 
+// Return a string representation
+inline std::string FixedJoint::to_string() const {
+    return "FixedJoint{ localAnchorPointBody1=" + mLocalAnchorPointBody1.to_string() +
+                        ", localAnchorPointBody2=" + mLocalAnchorPointBody2.to_string() +
+                        ", initOrientationDifferenceInv=" + mInitOrientationDifferenceInv.to_string() +
+                        "}";
+}
+
 }
 
 #endif
diff --git a/src/constraint/HingeJoint.cpp b/src/constraint/HingeJoint.cpp
index 990e7be1..bccd0cb1 100644
--- a/src/constraint/HingeJoint.cpp
+++ b/src/constraint/HingeJoint.cpp
@@ -42,8 +42,8 @@ HingeJoint::HingeJoint(uint id, const HingeJointInfo& jointInfo)
              mIsLowerLimitViolated(false), mIsUpperLimitViolated(false),
              mMotorSpeed(jointInfo.motorSpeed), mMaxMotorTorque(jointInfo.maxMotorTorque) {
 
-    assert(mLowerLimit <= 0 && mLowerLimit >= -2.0 * PI);
-    assert(mUpperLimit >= 0 && mUpperLimit <= 2.0 * PI);
+    assert(mLowerLimit <= decimal(0) && mLowerLimit >= decimal(-2.0) * PI);
+    assert(mUpperLimit >= decimal(0) && mUpperLimit <= decimal(2.0) * PI);
 
     // Compute the local-space anchor point for each body
     Transform transform1 = mBody1->getTransform();
diff --git a/src/constraint/HingeJoint.h b/src/constraint/HingeJoint.h
index fbcfeacf..435064d2 100644
--- a/src/constraint/HingeJoint.h
+++ b/src/constraint/HingeJoint.h
@@ -336,6 +336,9 @@ class HingeJoint : public Joint {
 
         /// Return the intensity of the current torque applied for the joint motor
         decimal getMotorTorque(decimal timeStep) const;
+
+        /// Return a string representation
+        virtual std::string to_string() const override;
 };
 
 // Return true if the limits of the joint are enabled
@@ -400,6 +403,17 @@ inline size_t HingeJoint::getSizeInBytes() const {
     return sizeof(HingeJoint);
 }
 
+// Return a string representation
+inline std::string HingeJoint::to_string() const {
+    return "HingeJoint{ lowerLimit=" + std::to_string(mLowerLimit) + ", upperLimit=" + std::to_string(mUpperLimit) +
+            "localAnchorPointBody1=" + mLocalAnchorPointBody1.to_string() + ", localAnchorPointBody2=" +
+            mLocalAnchorPointBody2.to_string() + ", hingeLocalAxisBody1=" + mHingeLocalAxisBody1.to_string() +
+            ", hingeLocalAxisBody2=" + mHingeLocalAxisBody2.to_string() + ", initOrientationDifferenceInv=" +
+            mInitOrientationDifferenceInv.to_string() + ", motorSpeed=" + std::to_string(mMotorSpeed) +
+            ", maxMotorTorque=" + std::to_string(mMaxMotorTorque) + ", isLimitEnabled=" +
+            (mIsLimitEnabled ? "true" : "false") + ", isMotorEnabled=" + (mIsMotorEnabled ? "true" : "false") + "}";
+}
+
 }
 
 
diff --git a/src/constraint/Joint.h b/src/constraint/Joint.h
index 10d1680e..92c413da 100644
--- a/src/constraint/Joint.h
+++ b/src/constraint/Joint.h
@@ -204,6 +204,9 @@ class Joint {
         /// Return the id of the joint
         uint getId() const;
 
+        /// Return a string representation
+        virtual std::string to_string() const=0;
+
         // -------------------- Friendship -------------------- //
 
         friend class DynamicsWorld;
diff --git a/src/constraint/SliderJoint.cpp b/src/constraint/SliderJoint.cpp
index 174ddb67..839cc4dc 100644
--- a/src/constraint/SliderJoint.cpp
+++ b/src/constraint/SliderJoint.cpp
@@ -41,9 +41,9 @@ SliderJoint::SliderJoint(uint id, const SliderJointInfo& jointInfo)
               mIsUpperLimitViolated(false), mMotorSpeed(jointInfo.motorSpeed),
               mMaxMotorForce(jointInfo.maxMotorForce){
 
-    assert(mUpperLimit >= 0.0);
-    assert(mLowerLimit <= 0.0);
-    assert(mMaxMotorForce >= 0.0);
+    assert(mUpperLimit >= decimal(0.0));
+    assert(mLowerLimit <= decimal(0.0));
+    assert(mMaxMotorForce >= decimal(0.0));
 
     // Compute the local-space anchor point for each body
     const Transform& transform1 = mBody1->getTransform();
diff --git a/src/constraint/SliderJoint.h b/src/constraint/SliderJoint.h
index 3fd0035e..e6ae05dd 100644
--- a/src/constraint/SliderJoint.h
+++ b/src/constraint/SliderJoint.h
@@ -337,6 +337,9 @@ class SliderJoint : public Joint {
 
         /// Return the intensity of the current force applied for the joint motor
         decimal getMotorForce(decimal timeStep) const;
+
+        /// Return a string representation
+        virtual std::string to_string() const override;
 };
 
 // Return true if the limits or the joint are enabled
@@ -401,6 +404,17 @@ inline size_t SliderJoint::getSizeInBytes() const {
     return sizeof(SliderJoint);
 }
 
+// Return a string representation
+inline std::string SliderJoint::to_string() const {
+    return "SliderJoint{ lowerLimit=" + std::to_string(mLowerLimit) + ", upperLimit=" + std::to_string(mUpperLimit) +
+            "localAnchorPointBody1=" + mLocalAnchorPointBody1.to_string() + ", localAnchorPointBody2=" +
+            mLocalAnchorPointBody2.to_string() + ", sliderAxisBody1=" + mSliderAxisBody1.to_string() +
+            ", initOrientationDifferenceInv=" +
+            mInitOrientationDifferenceInv.to_string() + ", motorSpeed=" + std::to_string(mMotorSpeed) +
+            ", maxMotorForce=" + std::to_string(mMaxMotorForce) + ", isLimitEnabled=" +
+            (mIsLimitEnabled ? "true" : "false") + ", isMotorEnabled=" + (mIsMotorEnabled ? "true" : "false") + "}";
+}
+
 }
 
 #endif
diff --git a/src/engine/DynamicsWorld.cpp b/src/engine/DynamicsWorld.cpp
index 8fb71e08..8f06ca74 100644
--- a/src/engine/DynamicsWorld.cpp
+++ b/src/engine/DynamicsWorld.cpp
@@ -548,11 +548,13 @@ Joint* DynamicsWorld::createJoint(const JointInfo& jointInfo) {
     // Add the joint into the world
     mJoints.add(newJoint);
 
-    // Add the joint into the joint list of the bodies involved in the joint
-    addJointToBody(newJoint);
-
     RP3D_LOG(mLogger, Logger::Level::Information, Logger::Category::Joint,
              "Joint " + std::to_string(newJoint->getId()) + ": New joint created");
+    RP3D_LOG(mLogger, Logger::Level::Information, Logger::Category::Joint,
+             "Joint " + std::to_string(newJoint->getId()) + ": " + newJoint->to_string());
+
+    // Add the joint into the joint list of the bodies involved in the joint
+    addJointToBody(newJoint);
 
     // Return the pointer to the created joint
     return newJoint;
@@ -614,12 +616,20 @@ void DynamicsWorld::addJointToBody(Joint* joint) {
                                                                      joint->mBody1->mJointsList);
     joint->mBody1->mJointsList = jointListElement1;
 
+    RP3D_LOG(mLogger, Logger::Level::Information, Logger::Category::Body,
+             "Body " + std::to_string(joint->mBody1->getId()) + ": Joint " + std::to_string(joint->getId()) +
+             " added to body");
+
     // Add the joint at the beginning of the linked list of joints of the second body
     void* allocatedMemory2 = mMemoryManager.allocate(MemoryManager::AllocationType::Pool,
                                                      sizeof(JointListElement));
     JointListElement* jointListElement2 = new (allocatedMemory2) JointListElement(joint,
                                                                      joint->mBody2->mJointsList);
     joint->mBody2->mJointsList = jointListElement2;
+
+    RP3D_LOG(mLogger, Logger::Level::Information, Logger::Category::Body,
+             "Body " + std::to_string(joint->mBody2->getId()) + ": Joint " + std::to_string(joint->getId()) +
+             " added to body");
 }
 
 // Return the next available joint Id
diff --git a/src/utils/Logger.cpp b/src/utils/Logger.cpp
index 9410cc29..2b213020 100644
--- a/src/utils/Logger.cpp
+++ b/src/utils/Logger.cpp
@@ -96,11 +96,15 @@ void Logger::log(Level level, Category category, const std::string& message) {
     auto now = std::chrono::system_clock::now();
     auto time = std::chrono::system_clock::to_time_t(now);
 
+    mMutex.lock();
+
     // For each destination
     for (auto it = mDestinations.begin(); it != mDestinations.end(); ++it) {
 
         (*it)->write(time, message, level, category);
     }
+
+    mMutex.unlock();
 }
 
 #endif
diff --git a/src/utils/Logger.h b/src/utils/Logger.h
index 8ce51fb3..879909c7 100644
--- a/src/utils/Logger.h
+++ b/src/utils/Logger.h
@@ -35,6 +35,7 @@
 #include <fstream>
 #include <sstream>
 #include <iomanip>
+#include <mutex>
 
 /// ReactPhysics3D namespace
 namespace reactphysics3d {
@@ -140,7 +141,21 @@ class Logger {
                 /// Format a log message
                 virtual std::string format(const time_t& time, const std::string& message,
                                            Level level, Category category) override {
-                    return message;
+                    std::stringstream ss;
+
+                    // Time
+                    ss << std::put_time(std::localtime(&time), "%X") << " ";
+
+                    // Level
+                    ss << getLevelName(level) << " ";
+
+                    // Category
+                    ss << getCategoryName(category) << " ";
+
+                    // Message
+                    ss << message << std::endl;
+
+                    return ss.str();
                 }
         };
 
@@ -186,7 +201,7 @@ class Logger {
 
             std::string generateCSS() const {
                 return "body {"
-                       "  background-color: #f7f7f9;"
+                       "  background-color: #e6e6e6;"
                        "  font-family: SFMono-Regular,Menlo,Monaco,Consolas,'Liberation Mono','Courier New',monospace; "
                        "} "
                       "body > div { clear:both; } "
@@ -222,16 +237,16 @@ class Logger {
                         "max-width: 800px; "
                       "} "
                       ".body > .category, .body > .message { "
-                        "color: #8bc34a;"
+                        "color: #00994d;"
                       "} "
                       ".world > .category, .world > .message { "
-                        "color: #4f9fcf; "
+                        "color: #3477DB; "
                       "} "
                       ".joint .category, .joint > .message { "
-                        "color: #aa00ff; "
+                        "color: #bf8040; "
                       "} "
                       ".proxyshape .category, .proxyshape > .message { "
-                        "color: #009933; "
+                        "color: #9933ff; "
                       "} "
                       ".warning { "
                         "color: #ff9900 !important; "
@@ -392,8 +407,7 @@ class Logger {
 
                 /// Write a message into the output stream
                 virtual void write(const time_t& time, const std::string& message, Level level, Category category) override {
-                    mOutputStream << std::put_time(std::localtime(&time), "%Y-%m-%d %X") << ": ";
-                    mOutputStream << message << std::endl << std::flush;
+                    mOutputStream << formatter->format(time, message, level, category) << std::endl << std::flush;
                 }
         };
 
@@ -408,6 +422,9 @@ class Logger {
         /// Map a log format to the given formatter object
         Map<Format, Formatter*> mFormatters;
 
+        /// Mutex
+        std::mutex mMutex;
+
         // -------------------- Methods -------------------- //
 
         /// Return the corresponding formatter