Path following - How I do I stick to the path but increase speed and thus velocity of a moving object?

            Vector3 position_Final = Vector3.Zero;
 
            // If the object is at the current destination node
            if (AI.AtNode(debug_Polygon[0].Position, nodes[node_Index]))
            {
                // Increase the node index
                node_Index++;
            }
 
            // Find next node
            Vector3 node = nodes[node_Index];
 
            Vector3 position_Start = debug_Polygon[0].Position;
 
            // Find the direction to the next node based on the object's position
            Vector3 node_Direction_To = node - position_Start;
            
            // Distance must be calculated from NON normalized direction
            float node_Distance_To = node_Direction_To.LengthSquared();
 
            // Now normalize the direction to the next node (for smooth movement)
            node_Direction_To.Normalize();
 
            // Set final position to current object position
            position_Final = position_Start;
 
            // Calculate the final position based on direction to the next node and object's speed
            position_Final += node_Direction_To * speed * (float)gameTime.ElapsedGameTime.TotalSeconds;
 
            // Calculate the distance travelled this frame
            float object_Distance_Travelled = (position_Final - position_Start).LengthSquared();
 
            // If the distance from the object's original position to its new position is greater than the distance to the next node
            // [I.e. The object has overshot the node by a certain distance]
            if (object_Distance_Travelled > node_Distance_To)
            {
                float object_Distance_Remaining = object_Distance_Travelled - node_Distance_To;
                Console.WriteLine("Overshot node by " + object_Distance_Remaining);
 
                // Set position to current node
                position_Start = nodes[node_Index];
 
                // Find the next node (ONLY IF NOT FINAL NODE)
                node_Index++;
                node = nodes[node_Index];
 
                // Find the direction to the next node based on the object's position
                node_Direction_To = node - position_Start;
 
                // Distance must be calculated from NON normalized direction
                node_Distance_To = node_Direction_To.LengthSquared();
 
                // Now normalize the direction to the next node (for smooth movement)
                node_Direction_To.Normalize();
 
                // Set final position to current object position
                position_Final = position_Start;
 
                // FIND NEW DISTANCE BASED ON: object_Distance_Remaining
                position_Final += ?????
            }

                                              

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