I thought that USB002 is your printer port. Sorry for the confusion. First you need to map your printer to any of avilable printer port. To do that follow the step as given below
1. Open the Printer Property Page.
2. Go to the share / sharing tab. Check the Share button and give the one printer share name, and click on ok.
3. Open the Command Prompt CMD
4. Excute the given command
5. net use lpt1: \\computername\printersharename /persistent:yes
Here you are actually directly the lpt1 printer port to your USB print.
/persistent:yes means to map every time you login so no need to run this command every time.
After doing so you can easily run the dos command.
COPY /B test.txt LPT1