What induces Gulliver to go on fourth voyage? Why does he employ recruit from Barbados? Why he repent this action?

After five months at home, Gulliver leaves his children and pregnant wife yet again to go on his fourth voyage, this time as captain. He tires of the monotony of family life in England. Not long into the trip, his crew mutinies, locking him into his cabin for a great deal of time and threatening to murder him. Eventually the crew, who plan to become pirates, drop Gulliver off on an unknown island