Shirou Sanada

The science officer aboard Yamato, Sanada is earnest and dedicated, his ideas frequently saving the ship from destruction. His limbs are bionic, the result of a childhood accident which claimed the life of his sister and left him bitterly resentful of science's arrogance. He was a classmate of Mamoru Kodai, and blames himself for not having repaired the Yukikaze properly before it went into battle. When Susumu Kodai becomes acting captain, Sanada is frequently a source of advice. Sanada is the elder spokesperson for the crew after the deaths of Okita and Engineer Tokugawa.

His Japanese name comes from real-life daimyo Sanada Masayuki. In 2199, he is also the XO (Executive Officer), second to Captain Juuzou Okita.

In the 2199 remake Sanada is the First Officer of the Yamato, and he does not mention anything to indicate the existence of his bionic limbs. Also, unlike the original series, where he blamed himself for the repair work of the Yukikaze, Sanada in 2199 felt guilty for Mamoru Kodai due to the fact that he did not inform Kodai that Operation M was actually a suicide mission to distract the Gamilas.

(Source: Yamato Wiki)