(Portland, OR)  --  Two people are facing charges in connection to an armed robbery in Troutdale.  Police arrested Joshua Vaughn Miller and Sandra Dee Miller early yesterday morning following a brief car chase on Interstate 84.  Police say the two entered the Safeway gas station on Cherry Park Road wearing masks and armed with a knife and a gun on Sunday and robbed the attendants.  Police later found their car abandoned on Southeast Bull Run Road in Clackamas County and used a K-9 unit to track them down and arrest them.