Seven-functional underwater mechanical arm system

The invention aims to provide a seven-functional underwater mechanical arm system. The seven-functional underwater mechanical arm system comprises a paw, a wrist, a first joint, a second joint, a third joint, a fourth joint and a fifth joint, wherein the first joint comprises a base and a first hydraulic cylinder; the second joint comprises a first connecting rod and a second hydraulic cylinder; the third joint comprises a second connecting rod and a third hydraulic cylinder; the fourth joint comprises a third connecting rod and a fourth hydraulic cylinder; the fifth joint comprises a fourth connecting rod and a fifth hydraulic cylinder; the paw comprises a front wrist end, a first finger end, a second finger end, a first main connecting rod, a second main connecting rod, a first auxiliary connecting rod, a second auxiliary connecting rod and a sixth hydraulic cylinder; the wrist comprises a connecting piece, a rotary motor and a fifth connecting rod. The seven-functional underwater mechanical arm system is simple and compact in structure and high in loading capacity, has seven degrees of freedom, and has higher applicability to deep sea exploration and corresponding seabed operation; the mechanical paw is detachable and replaceable.