TriNano: CMMs With Nanometer Uncertainty for a Micro Price
TriNano is a new nano/micro CMM to measure objects with sub-millimeter features in three dimensions and with nanometer uncertainty. Current micro CMMs comply with the Abbe principle in 2D or even in 3D, which is a preferred method to reach 3D nanometer uncertainty. Most of these CMMs are the result of academic research, in which the challenge is to achieve the lowest uncertainty over a large measurement range. This resulted in technologically advanced, but expensive systems.
Within the precision manufacturing industry a large measurement range often is not the most important factor. Most objects (or their molds) have dimensions of a few centimeters (lenses, watch base plates, small gears, etc.) and fit in a match box. From now on, a cost effective device is available to measure these items in true 3D (including sidewalls, steep slopes and undercuts) with nanometer uncertainty.
Working principle
In order to reach nanometer uncertainty while keeping the device cost efficient, a new working principle has been developed. This principle employs a moving work piece table and a stationary probe. The table moves in three directions by means of three identical linear translation stages. These stages are positioned orthogonally and in parallel (like a tripod). On each linear stage, the scale of an optical linear encoder is mounted. At the point of intersection of the measurement axes of these encoders the probe tip is located. As the orientation of the encoder scale does not vary with respect to the probe, the TriNano complies with the Abbe principle over its entire measurement range.
Besides the obvious cost savings when manufacturing three identical axis, this configuration enables fast measurements through its superior dynamical behavior. Furthermore, complying with the Abbe principle in 3D greatly reduces non repeatable errors and enables a TriNano N100 to reach a 3D uncertainty of 100 nanometer over its entire measuring range. Therefore, TriNano is an optimal solution in terms of cost price, speed and versatility for measurements on small features requiring 3D nanometer uncertainty.
More information
For more information (including a video of a TriNano N100), please visit www.trinano.eu.