robot rotate 90 degrees right or left

Hi

how could I make a robot rotate 90 degrees right or left? or any other angle...

the robot will be used indoors and has 4 wheels...

which sensor would be indicated?

Thanks

mateusguilherme:
which sensor would be indicated?

I'm not sure what you mean here but sensors sense things. They don't make things move. Motors or servos make things move. If you want 90 degrees in either direction then it sounds to me like you are looking for a servo.

Gyro?

Gyro seems to be a good solution... thanks

gyros have long term drift, but for short-term manoeuvres will be pretty good.