[Help] communication with 3 Arduinos (Seriel, Canbus)

Hi Guys i need your help.

I have a Projekt with a lot of simple Sensors and with 3 Arduinos. My idea is that one Arduino is a Master and the other two Arduinos are the Slaves, BUT the Slaves talk back to the Master with the updated values or with other values.

I dont know how i can make this communication happend. I tried wireless over Radio but the Receiver cant talk without a Timing parallel with two Transmitters.

The next idea was a Serial communication (TX,RX) but is this possible to code with the sensor values exchange?

Another idea was a CanbusShield. Whats your experience with that one?

Thank you for your help! (sorry for the bad english)

Best regards from Germany

I tried wireless over Radio but the Receiver cant talk without a Timing parallel with two Transmitters.

What? I can call you on your cell phone, from my cell phone, and neither of our phones needs to know anything about the time, or any timing, on the other phone.

The next idea was a Serial communication (TX,RX) but is this possible to code with the sensor values exchange?

Of course. The serial port is used to send, and receive bytes. ALL data is made of bytes.

Another idea was a CanbusShield. Whats your experience with that one?

Adding another complete layer of complexity is not warranted.