Posted to News on 3rd Jan 2007, 00:00
Industrial robots get touchy-feely for delicate tasks
Force/torque sensors can be used in almost any robotic application. They are in use at many of the major universities and also in research labs including Airbus, JET, JPL, Sandia, Los Alamos and Oak Ridge. Robots can achieve a higher level of performance and flexibility when equipped with force/torque sensors. They can also perform some tasks that would be otherwise impossible.
When choosing a sensor for robotic applications, several characteristics are of great importance. Robots are often crashed, so the sensor should have a very high overload rating. Robot applications require high positional precision, so the force/torque sensor should be very stiff. A force/torque sensor should also have a large measurement range, good resolution and a low-noise output.
TIA's product portfolio incudes the ATI range of force/torque sensors that has been developed and manufactured since 1983, resulting in a very large installed base within industry and research. Maximum torque sensing ranges vary from +/-0.5Nm to +/-1400Nm. Six-axis sensors typically use strain gauge technology to convert force and moment loads into electrical signals. The ATI range uses silicon strain gauges because of their low-noise output and high gauge factor, or sensitivity. This results in a sensor with very high overload protection and low noise. The design of a six-axis force/torque sensor is essentially the same whether the sensor is 17mm or 330mm in diameter. A central hub is attached to the sensor's outer wall by three beams. Each beam has four silicon strain gauges wired as two half-bridges. The sensor outputs six channels of raw strain gauge data.
