Grimes, who missed almost all of last season with an Achilles tendon injury, has signed a one-year contract with the Miami Dolphins.
Grimes started 28 games for the Atlanta Falcons in 2010-11 but was hurt in the opener last year. He was undrafted and broke into the NFL with the Falcons in 2007. Grimes, who has 13 career interceptions, will compete for a starting job with the Dolphins. They lost Sean Smith via free agency to the Kansas City Chiefs.

Louis, still rehabilitating from a season-ending knee injury last November, has signed with the Miami Dolphins.
The 6-foot-3, 320-pound Louis spent the past four seasons with the Chicago Bears, where he made 28 starts at guard and tackle. They drafted him in the seventh round in 2009. Louis tore the anterior cruciate ligament in his left knee and missed the final five games of the season.

Garner has re-signed with the Miami Dolphins. The signing announced Tuesday comes barely 24 hours after tackle Jake Long, the overall No. 1 draft pick in 2008, left a hole in the line by signing with the St. Louis Rams. Garner started four games last year.
The 6-foot-7, 325-pound Garner is entering his sixth NFL season. He has played at all five positions on the line, with five starts at left guard, four at right tackle and four at right guard. Garner originally was a seventh-round draft choice of the New York Jets in 2008.

Gibson has signed with the Miami Dolphins, giving young quarterback Ryan Tannehill a third new target through free agency.
Gibson, who signed Friday, spent the past four seasons with the St. Louis Rams, where he made 38 starts. Last year he had 51 receptions for a career-high 691 yards and five touchdowns while starting 13 games.