Free Shipping but still use UPS

Is there a way to allow customers to get Free shipping and hikashop still be able to use UPS as the shipping method(or any other Shipping provider actually)?

So basically the user will select UPS but not be charged for shipping, however still communicate with UPS's api and process the order like normal.

Hi,

UPS and USPS plugins have been develop by external people who share their code with the community.
Theses plugins does not support rules like the manual shipping plugin does.

I am afraid that the present solution would be to modify the UPS plugin in order to but new rules into.
Best way would be to duplicate the plugin in order to have an another plugin name (so it would be possible to update HikaShop without loosing modifications).

Regards,