This paper presents a novel design for a compact, lightweight 6-axis
force/torque sensor intended for use in legged robots. The design promotes easy
manufacturing and cost reduction, while introducing innovative calibration
methods that simplify the calibration process and minimize effort. The sensor's
advantages are achieved by streamlining the structure for durability,
implementing noncontact sensors, and providing a wider sensing range compared
to commercial sensors. To maintain a simple structure, the paper proposes a
force sensing scheme using photocouplers where the sensing elements are aligned
in-plane. This strategy enables all sensing elements to be fabricated on a
single printed circuit board, eliminating manual labor tasks such as bonding
and coating the sensing elements. The prototype sensor contains only four
parts, costs less than $250, and exhibits high response frequency and
performance. Traditional calibration methods present challenges, such as the
need for specialized equipment and extensive labor. To facilitate easy
calibration without the need for specialized equipment, a new method using
optimal control is proposed. To verify the feasibility of these ideas, a
prototype six-axis F/T sensor was manufactured. Its performance was evaluated
and compared to a reference F/T sensor and previous calibration methods.Comment: 12 pages, 13 figures, 9 table