Ensuring data integrity performance of speed log sensors
Nortek modified the speed log by installing a higher-specification AHRS to help the team measure the orientation of the sensor relative to the water. The sensor’s attitude is important when measuring forward velocity and the AC75’s orthogonal drift sideways (leeway). Nortek also modified the firmware to allow the speed log to measure at up to 50 knots. Throughout this process Nortek supported Ineos Team UK in planning and executing the installation of the speed logs, along with technical support for the devices and analysis to ensure data integrity and quantify the performance of the sensors.
The two speed log sensors successfully provided velocity measurement relative to different layers in the water column below the AC75 foils. “This was data that had never previously been collected on a foiling America’s Cup boat. Unfortunately, the insights to boat performance will remain confidential to the team,” explains Mark Chisnell.
“We’re very happy to have had Nortek as a partner in this project. The Nortek Speed log is an impressive technical achievement. Having accurate knowledge of the inflow vector to the lifting foils has given the team new insights into the boat’s dynamic behavior and performance,” says Nick Holroyd, Technical Director at Ineos Team UK.
Building on a tradition of marine problem-solving
Nortek has a long tradition of solving technically challenging problems in the marine environment.
“Team Ineos UK approached Nortek knowing that we had been down a similar path before. However, the challenge presented was to measure speed through water accurately from a foiling sailing machine – something that has not been done before now,” says Torstein Pedersen, Development Engineer at Nortek.
The success of this solution was very much cooperative: Nortek provided the modified electronics and operational advice, while the Team Ineos UK technical team ensured an optimized installation in the foil.
“We are familiar with an iterative process for these custom solutions, but in this instance I think we were all surprised how well it worked right out of the gate. When we now watch the Britannia yacht tearing across the ocean surface, balanced merely on the foils, it is hard to believe that there is a little speed log just below the surface pinging away and answering questions,” Pedersen adds.