The 21-year-old said goodbye to his colleagues and supervisor Kenneth Long. Right before he left, he told Long he was going to make it a two-day drive and stop one night to camp out.
Except Robbi, a happy-go-lucky kayaker from Orleans, California, never made it to orientation the next day.
The SearchGas station surveillance footage in Garden Valley, Idaho, shows what appears to be Robbi's green 1997 Subaru Legacy with the California plate 6 CCP 540, according to ABC News. His cell phone was picked up in the nearby town of Lowman.
He tied two kayaks to the roof of his car before he hit the road. "His parents are confident that it's his car," Sheriff Ben Roeber of the Boise County Sheriff's Office tells PEOPLE. "Even though it looks like it only has one kayak on top of it. We are still pursuing it."
Robbi's family members and friends have flown to Idaho to help with the search.
"There are two routes to get to Missoula," Roeber says. "Either one will lead you through small towns and then periods of 40 to 50 miles with no resources. We are concentrating our search on the areas that are hard to see from the highway."
When the police pinged his cell phone last Friday, they were not able to get an exact location because they only have one cell phone tower in that area. There has also been no credit-card activity.
"This is not a kid that was going to go on a solo trip throughout the woods," says Roeber. "So it's obviously very concerning when he was going from point A to point B and never showed up at point B."
A Facebook page called Finding Lucius has been founded to help with the search and share information. A GoFundMe page was also created to raise money for search efforts.
'Out of Character'"He is a very responsible and thoughtful kid," Long tells PEOPLE. "It is very out of character for him to just blow off school and not tell anyone."
He describes Robbi as a hard worker, eager to learn and always happy.
"He has one of those infectious personalities that makes you smile. He was always early to work and was very responsible and thoughtful."
His friends couldn't agree more.
"He is from the mountains, grew up outdoors and was so ready to explore," Jonathan Cizmar, 27, who went to Feather River College with Robbi tells PEOPLE. "He is so smart politically and analytically. I don't know half as much as he does and he's a lot younger."
The last time Cizmar saw Robbi was when he turned 21 a few months ago. They went out with just a couple people and had a laid back night.
"I don't know what happened to him and that's the problem. He is always on the ball so this just doesn't make sense," Cizmar says.