When designing a vehicle or any other object that is required to move through the air, wind tunnels are commonly used to help perfect the characteristics of the air flow across the subject’s surfaces.

An acknowledged global expert in this field is East Sussex-based Ate Aerotech, which specialises in designing, manufacturing and installing wind tunnels and related test equipment for customers in a variety of industry sectors — including aerospace, motor-sport, automotive, defence and industrial research.

The Large Cartesian Flow Survey Systems supplied by Ate Aerotech offer a comprehensive solution for accurate wind-tunnel air-flow measurement.

They comprise a series of beams mounted on precision rails and a telescopic strut, all located inside the wind tunnel to accurately position a range of probes that measure parameters such as pressure, velocity, temperature or acoustic noise within the wind tunnel’s test section.

The probes are traversed around the model under test to survey user-selected locations, thus providing a profile of the measured parameters.

Before a wind-tunnel test is undertaken, it is vital to calibrate the positional accuracy of the system’s various movable elements, thereby enabling the company’s advanced control algorithms to precisely achieve the required profiles.

Faced with the need to perform 3-D metrology procedures in such a large-scale environment, Ate Aerospace recently searched for a precise non-contact co-ordinate measuring system that could provide high levels of calibration accuracy while also offering both ease and speed of use.

Having considered several options, the company purchased a VantageS Laser Tracker from Rugby-based Faro Technologies UK Ltd (www.faro.com) to be incorporated into one of its systems for a Chinese client.

The VantageS is designed to provide high levels of accuracy over long distances, allowing Ate Aerotech staff to undertake precise wind-tunnel calibration by accurately plotting the position of each of the system’s moving parts
at their start positions, and when each element is traversed throughout a predetermined grid pattern.

The resulting data allows micro adjustments to be made, so that the maximum accuracy potential of the system can be achieved.

Additional unit

As well as calibration tasks, many other uses have been found for the Faro Laser Tracker — so much so that Ate Aerotech bought a further unit for its own use.

As well as being used to verify the accuracy of fabricated parts and assemblies in-house, the portability of the Laser Tracker means that company staff can take it all over the world and quickly verify the accuracy of each new wind-tunnel installation.

Furthermore, Ate Aerotech now offers its customers a Faro VantageS as optional equipment with every wind-tunnel system it installs.

Ate Aerotech managing director Richard Mower said: “We are an ISO 9001-accredited company with a wealth of experience in designing, manufacturing and installing wind-tunnel test equipment.

“We provide highly accurate and cost-effective systems for a variety of applications and can deliver a wide range of standard ‘off the shelf’ products or tailor-made solutions that exactly meet our customers’ specific requirements.

“As part of our quest for constant improvements — and given the considerable size and volume of our wind-tunnel systems and our demanding accuracy standards — we recently searched for a non-contact measuring system that could provide highly precise 3-D dimensional readings over long distances.

“We found that the Faro VantageS could achieve readings accurate to 0.015mm throughout the volume of our wind tunnels, so we were happy to place an order.

“Moreover, as well as improving our accuracy capability, the unit’s speed is such that we have shortened the time required for our manufacturing, assembly, installation and system calibration tasks.”

Faro says that its Vantage range offers the only laser trackers that measure angle and distance with a single laser, thereby ensuring improved reliability, as the errors and drift associated with two-beam tracker technology are eliminated.

The VantageS, as purchased by Ate Aerotech, is intended for short- to long-range measurement applications (up to 80m); and with a fast data output rate of 1,000 points per second, it provides feedback for high-speed motion control and high-density scanning, making it ideal for automated applications.

The VantageS uses RemoteControls work-flow, which streamlines laser tracker operations and allows a single user to control functions such as live video feed and tracker movements from a mobile phone or tablet — from anywhere in the measurement area.

To further improve portability, continuous operation is available with ‘hot swappable’ battery packs that eliminate the need for an external AC power supply.

Rated at IP52 for dust- and water-resistance, the VantageS has been rigorously tested for resistance to shock, vibration, temperature cycles and humidity, so it can be used in industrial environments.