Wave-powered unmanned surface vessels (USV) could be used for maritime rights and law enforcement, researchers said, as Beijing faces heightened tensions in contested waters including the South China Sea. Writing in the latest issue of Naval and Merchant Ships, owned by China State Shipbuilding Corporation, Chen Xin and Chen Ruimiao said the self-powered vessels could be “of great value” to the sustainable management of distant waters. By converting vertical wave motion into forward thrust using