hi i would like some assistance i have a project that i would like to build where it is a waring system for a car where it will detect other vehicles and warns the driver in advance using a camera and a lcd screen.
wrong category
A project with specifications, parts, drawings, code, functions and power, or something a multi-billiard-Euro company developed for an automobile?
Start with what you know... continue with what you learned... add what you need for help.
Those exist today in several forms. Do you plan on selling this? Do you have any background in automotive requirements, regulations, etc.
Your topic has been moved to a more suitable category of the forum. There is no emergency in this and it's not related to COVID-19.
Hi, @sie123
Welcome to the forum.
Can you please tell us your electronics, programming, arduino, hardware experience?
Thanks.. Tom.. 
Do you have any specifications for the other vehicles that will be detected? What will other vehicles look like to the warning system? How much time will be allowed for the detection?
hi Paul
the vehicles im talking about is the special ones that sits on the side of the road with windows at the back that type
Is there something missing in translation?
Tom...
Recognising g a car with a camera is not an easy task.
You need to specify what you are trying to do in detail .
Is this a school project ?
I really suspect the OP is looking for a "radar detector" and is trying to describe an officer in a parked car using radar gun to monitor vehicle speed.
hi
not its not im a fully qualified electronics repairs engineer and its a project that i would like help me
hi paul
its a speed camera van i would like to achieve a visual system to detect the van before it can detect you and warn you
Do you not understand that by the time you detect the radar signal from the van, you have already been detected and photographed?
For me it is quite clear ( can't qualify how clear )!
Electronic countermeasures. You receive the pulse sent by the transmitter, manipulate the pulse to suit your needs, amplify the pulse and transmit back to the receiver. The amplified return will be selected over the original (weaker) return by the receiver as the valid return. Things you might try: Drive at or below the speed limit.
hi Paul
with that it would be tested and adjusted until its right
this is why you would use a high res camera on the device
Are you thinking to put a parabolic dish and a 10gHz receiver to detect the radar. That is the only difference between a normal van and one used for radar speed control.
Useless. The trick is to find the fastest guy on the road, pull up next to him for a sec then overtake him then let off the gas a little so you slow down.
Let him overtake you to fly past and catch the radar trap.
I call these fools my "Judas Cars"