Motor and preasure sensir

I am trying to develop a trap door..that revolves 90 degrees at a time.this is trigerred by a pressure sensor...can someone please assist me or point me in the right direction..... i want a sketch or assistance with one and the motors that i should utilise....please help this is for a school project....

Draw a picture of the mechanical arrangement and show the approximate dimensions and weight.

It sounds like you are a beginner at all of this. Start with the basics.

Step 1: Go through several beginner Arduino tutorials to learn how to write a sketch.
Step 2: Learn to connect and read the pressure sensor sending the reading to a serial monitor.
Step 3: Learn how to connect and drive a motor or servo
Step 4: Put it all together

We can help you with specific questions or problems, but if you want someone to design your whole system and write all the code put a request in Gigs and Collaboration and be prepared to pay someone.

The motor will totally depend on the torque required which will depend on the weight, dimensions and mechanism. A small doll house type of door can be controlled by a cheap RC servo, which would be very easy. A full size door will require a lot more torque and power.