Most manufacturing floors now days have overhead cable drops. Can be cable with junction boxes and a drop at every lane or so, then the cart will have a female connector cable that will connect to the dropped cable and connect to, typically, an ERP system or SAS, something like that.
But WiFi should work.... what is the issue with it? Speed or latency? A decent WiFi network can have excess capacity relative to your provider. Test the root speed and latency of the provider first, make sure they are not haircutting your service. A speedtest like ookla gives you the Ping first, thats the latency that typically kills live audio and video.