Overview

When a multiple championship winning F1 team selected RUAG’s renowned aerodynamic balances for their wind tunnel based aerodynamic development, they needed an equally outstanding data acquisition hardware solution to match up.

We pioneered in-model data acquisition systems in the mid-nineties with our compact Mistral IJBs (Intelligent Junction Boxes), which included precise, accurate and high-resolution balance and strain gauge data acquisition modules. This meant we were ideally positioned to build the next generation of robust in-model instrumentation modules.

Challenge

RUAG is a Swiss Technology Company with a strong aerodynamic test and development department that builds and supplies a range of renowned aerodynamic balances. The outstanding precision, repeatability and accuracy of these balances is only realised if coupled with an equally exceptional data acquisition solution.

The Cosworth Mistral IJB system modules were behind all F1 constructor’s championships for over a decade since 2000. They offered unrivalled repeatability and stability which enabled motorsport customers around the world to find even minute incremental improvements.

The challenge was to build on that experience to create the next generation solution, harnessing the standard EtherCAT® real-time communications protocol for interoperability and optimal time synchronisation.

Solution

The Cosworth ESG16 was developed in 2015 and has since found enthusiastic customers in F1, as well as with Penske Racing for both their Indy and NASCAR programmes.

The compact yet rugged IP67 aluminium module offers 24-bit resolution and ratiometric measurement. With outstanding accuracy of +/- 0.03% and repeatability of +/- 0.06% FS over one year, the ESG16 delivers the performance demanded by leading motorsport teams.

By using the open and widely used industry standard EtherCAT® that offers high speed and sub-microsecond time synchronisation, the ESG16 interfaces with data acquisition systems, such as Cosworth’s Diablo software.

Technical Specifications

• 24-bit resolution
• Ratiometric measurement (six-wire connection) for optimal accuracy and stability
• Simultaneous sampling at up to 2kHz via Delta Sigma ADCs
• Sensitivity ranges between +/-0.24mV/V and +/-3.79mV/V, configurable per channel
• Accuracy better than +/-0.03% FS @ 25degC (typically +/-0.01%)
• Repeatability +/-0.06% FS over one year and operating temperature range
• Temperature dependency 5ppm/degC
• Wide operating temperature range -25 o C to +60 o C
• Compact (126 x 60 x 22mm), rugged IP67 aluminium housing
• Standard EtherCAT slave device, interoperable with any EtherCAT master

Each of the ESG16’s two input ports can digitise signals from one of:

• A six-component balance, with up to eight strain gauge full bridges plus two PT100 temperature sensors
• Two 3/4 component wing balances, sharing excitation and sense lines
• Four separate strain gauge full bridges, with independent excitation and sense lines