Roberts was an instructor at
St. Augustine's University in
Raleigh, North Carolina, from 1937 to 1939. He returned to St. Augustine's from 1941 to 1942 as an
associate professor of physics. and published technical papers and journal articles about microwave theory. He later founded three other Massachusetts-based microwave research companies: Bomac Labs in
Beverly, Metcom in
Salem, and Elcon Labs in
Peabody. In 1967, Roberts joined
NASA to become chief of its Microwave Laboratory at the
Electronics Research Center in
Cambridge, Massachusetts. Roberts was among the highest ranking African-American space program staff at NASA while the
Apollo program was underway. He told the
Bay State Banner that he had chosen to join NASA for the research opportunities, and because of its research facilities, which were more sophisticated than the ones at his companies. The Microwave Lab focused on microwave technology as applied to communications systems, and research topics included
microwave antennas and
solid state circuits. Roberts stayed at NASA until 1970, at which point he joined the
United States Department of Transportation to continue his microwave research at the
John A. Volpe National Transportation Systems Center. He spent several years researching the application of microwave technology to
air traffic control, before becoming the director of the Center in 1977. He retired in 1989. Roberts belonged to the
American Association for the Advancement of Science, the
American Physical Society, the
American Mathematical Society, the
American Institute of Aeronautics and Astronautics, and the
Society of Automotive Engineers. He was a fellow of the
Institute of Electrical and Electronics Engineers (IEEE), and for a time belonged to IEEE's Education Committee. Roberts also was a member of
Phi Beta Kappa. == Personal life ==