Easy calibration for portable measurement arm

A key advantage of the specification of the Polar 3D articulated measuring arm is the capability for the operator to perform quick and simple on-site calibration using a verification artefact.

A key advantage gained from the specification of the Polar 3D articulated measuring arm, developed and marketed by OGP UK, is the capability for the operator to perform quick and simple on-site calibration using a verification artefact.

In addition, with the ability to monitor ambient temperature, the arm will automatically warn operators of any change during the measuring cycle, so they can quickly remodel and zero-out the arm's 39 different parameters against the simple step by step calibration procedure.

Polar, which is available with 2000 or 3000mm diameter spherical operating volumes, is believed the only measuring arm of its type to include an artefact in the carrying case as part of the 'ready to measure' package.

This is advantageous because it instils total confidence to the operator that the arm is able to maintain its 140-micron accuracy tolerance throughout the spherical operating volumes.

The test procedure takes around 2min while the probe is contacted with the datum cones of the artefact and the arm exercised around which allows the software to compute and account for changes of angle and lengths of the arm.

Polar is then ready to go with optimised measuring accuracy.

Polar is totally portable and its carrying case will easily fit into the boot of a car.

The package includes a laptop PC which contains calibration and operational software with accredited algorithms and the artefact.

The measuring arm is ideal for tasks such as on-machine measurement or the local checking of components as diverse as large castings, mouldings and dies, exhaust systems and pipe bends, automotive panels and chassis, aerospace structures, assemblies and calibration fixtures.

It can also check features such as geometric relationships avoiding the need for strip-down or the logistics of transport to a conventional measuring facility.

Also included within the software specification is the capability to reverse engineer data from unknown shapes with output able to interface with all native CAD formats.

Polar comprises three articulated or universal joints which connect two tubular lightweight arms from the base to the measuring probe holder.

This assembly creates six degrees of freedom allowing the probe to be manipulated by the operator within its respective spherical radius of 1000 or 1500mm, according to the model specified.

The award-winning Polar has been progressively developed by OGP UK to improve its measuring capability.

Now incorporated within each joint of the arm are specially developed rotary encoders by the world-leader in encoder technology, Heidenhain of Germany.

These encoders not only keep the arm slim and therefore lighter, they enable higher accuracy and repeatability to be achieved over long periods of measurement.

Polar is rugged and weighs just 8.5kg.

It can also be specified with a choice of software to suit the intended use.

Back to top