Week 7 Challenge

SOLUTION :

We can from above image shows the force acting on a vehicle here are,

• Ftr = Tactive Force
• Fa = Aerodymanic drag resistant force
• Fg= Gradient Resistance force
• Fr = Rolling resistance force.

• Here the Tractive force is the force applied produced by the vehicle powertrain we will now see the quations of three main forces and will implement this by matlab Fcn block

Aerodynamic drag :

• Here Aerodyamic Drag is a force which the on coming air applies on a moving body.
• Its is the reistance offered by the air to the movement of the body.
• So when a car is moving it displaces the air However it affects the car's speed and performance
• It is the aerodynamiv drag or the friction offered by the air to a vehicle

Aerodynamic Drag= 1/2*p*Cd*A*V2

ROLLING RESISTANCE: It is the friction between the road and tire in a circular motion

Frr = M*g*mu*cos(u)

Force of aceelration :

• The acceleration force refers to the vehicle resistance to speed varitaions
• This force holds you back when you increase your speed and also moves you forward when you slow down in other words it means that you consume energy to acclerate up to as certain speed but can recover part of that energy when you decelerate allowing you to drive a certain distance without consuming fuel in equations it is simply written as
• F=m*a where m is mass and a is acceleration.

VEHICLE MODEL:

Inside View of vehicle block is shown below:

Drag force gradient force and rolling resistance force implemented using Fcb block

Working of MOdel:

The input to the vehicle block is tractive force this tractive force is teh force which is applied by the powertrain to the vehicle body we have given tractive force directly as a input its values are in newton.

The vehicle paramertes is loaded using mat files. The parameters value is shown below

Parameters value

Vehilce mass 1kg

Gravitation force 9.81

RR coefficient 1.25

Drag Coff 2.5

Grade or angle 0.

RESULTS: