The Octagrabber.....
https://www.nasaspaceflight.com/2021...y-octagrabber/
SpaceX evolving fairing recovery plans, taking advantage of Octagrabber in pursuit of rapid reusability
.....On several missions, the “
Octagrabber” system on board both drone ships has made the difference between a successful recovery and losing a booster at sea.
On the morning of November 19, 2020, SpaceX’s
Falcon 9 core B1061 returned to Port Canaveral aboard the deck of drone ship
Just Read the Instructions. Just days before, B1061 and its second stage blasted the company’s first operational crewed mission,
Crew-1, to orbit.
As B1061 appeared over the horizon, it was immediately noticeable that something was wrong. As the drone ship neared port, it became apparent that the booster was secure on the deck but leaning almost 10 degrees.
Around one month later, core B1051, which had just supported the
SXM-7 mission, arrived in port with a similarly dire lean. This time, the lean was so bad that one of the booster’s four landing legs was not even resting on the drone ship’s deck.
Often battered by high seas, howling winds, and raging storms, the drone ships and their recovery crews face a difficult task during the several day journey to and from recovery zones at sea. Landed boosters are kept secure thanks to a massive white robot dubbed “Octagrabber.”....
When not needed to secure a booster, Octagrabber rests safely in its garage, hidden behind the drone ship’s blast wall.....
After a landing, Octagrabber rolls on its two massive treads from its garage and stops directly underneath the booster. Four arms then connect to Falcon 9’s base, called the octaweb. These arms connect to the same hold-down points used to secure the rocket to its launch pad before liftoff.
While Octagrabber is quite small compared to a Falcon 9 booster, it still provides a strong enough grip that prevents the booster from sliding or falling off the deck because a Falcon 9 is quite light after landing; now empty of fuel, most of the booster’s mass is at the bottom where the nine Merlin engines are located.
Octagrabber itself is very large and flat, providing a stable base for the rocket to be secured to versus resting solely on its landing legs.......