Many manufacturers who produce inertial measurement units (IMUs) continue to test and calibrate them using a device called a two-axis table. These devices offer a degree of affordability, thanks to a mathematical “trick” that allows an IMU’s six degrees of freedom to be excited with the table’s two degrees of freedom. However, these two-axis tables also come with an additional idiosyncrasy: they have a lower rate capacity on the outer axis than the inner axis.
While determined engineers may have used these legacy tables to meet past testing requirements, new generations of IMUs almost always require their gyroscopes to be tested at rates that exceed the capabilities of a two-axis system (on its outer axis). While manufacturers began to contact Ideal Aerosmith for help in overcoming this challenge, some of them simply did not have the time or resources to replace their two-axis tables.
One question kept coming up: Would it be possible to retrofit existing two-axis tables with the capabilities to effectively test and calibrate newer IMUs?