Robert P. Caren, 54, corporate vice president-technology, has been named corporate vice president-science and engineering of Lockheed Corp., effective Jan. 1. Caren will succeed Robert H. Wertheim, 65, who is retiring. Raymond Capiaux, 60, vice president and assistant general manager of the Lockheed Missiles & Space Systems Group's Astronautics division, will become vice president and general manager of the division and a corporate vice president. He will replace Robert M. Powell, 65, who is retiring. Corporate Assistant General Counsel Robert C. Gusman, 56, will also become assistant secretary. As assistant secretary, he will replace David B. Bowman, 58, whose promotion to vice president-secretary and assistant general counsel was announced in October.