Data loss due to simultaneous transmission in ZigBee

I'm designing a multi-agent robotic application, where robots communicate through ZigBee modules. If two (or more) robots send their data simultaneously (at the same time) will it cause data loss at the receiver?

Consider multiple senders and one re开发者_JAVA百科ceiver (where senders send data simultenously and receiver receives them and perform certain tasks).

If you are using a full ZigBee stack (something like XBee, Freescale, etc.), it should handle checking for a clear channel before sending as well as resending data if there is failure. Our networks have hundreds of ZigBee nodes and we very, very rarely see any data loss.