Hi Peiyao,
Yes, use the UploadRecordings command to create a trial that will send the recordings. You can pass "noblock" as the second parameter if you don’t want each upload request to slow down your experiment (take a look at the example script). Just make sure you’re using at least PennController 1.8, as the command was introduced with that release.
Also, using "noblock" will most likely have the requests generated by the UploadRecordings trials complete during a subsequent trial, so the lines added to the results file once upload is complete will be associated with whatever trial is currently running, instead of with their corresponding UploadRecordings trial.
Jeremy