Rapidly repositionable powered support arm

A repositionable, lockable support arm assembly for surgical and other tools includes a base arm having a lower end and an upper end, a distal arm having a proximal end and a distal end, and a centraljoint, typically a rotational joint, directly or indirectly linking the upper end of the base arm to the proximal end of the distal arm. A lower joint, typically a spherical joint, is positioned at the lower end of the base arm, and an upper joint, also typically a spherical joint, is located at the distal end of the distal arm, A locking mechanism is coupled to the base arm at a location above the lower joint and is configured to simultaneously deliver locking forces to the lower joint, to the rotational joint, and to the upper joint. The locking mechanism usually includes a powered, bilateral force generator for actuating the locking mechanism. 种用于外科手术工机具和其它工具的可重新定位的可锁定的支撑臂组件包括：基座臂，其具有下端和上端；远侧臂，其具有近端和远端；和中心接头(通常为旋转接头)，其将基座臂的上端直接或间接地联接于远侧臂的近端。下接头(通常为球形接头)位于基座臂的下端，并且上接头(同样通常为球形接头)位于远侧臂的远端。锁定机构于位于下接头的上方的位置处被联接于基座臂