This robot has several movable joints.
The moving parts need regular lubrication.
固定 means fixed or stationary, the opposite of 可動 which means capable of moving.
可動 means 'movable' and describes parts designed to shift, directly opposing the physically fixed sense of 不動.
稼働 (same reading かどう) means the operation or running of machinery, whereas 可動 describes the mere capability of being moved.
Compound of 可 (possible) and 動 (move), literally 'able to move'. The reading is on'yomi.