Log Scanner

How to improve your performance

LogScanner™ is a log analysis tool that provides insight into how to improve your performance on the racecourse. It can read Ockam, Expedition and NMEA0183 log files and show them in ways that lets you find out what happened:

• Where your performance was above and below par
• Why the performance was below par
  • Bad and/or inconsistent sail trim and steering
  • Ability to hit target speed
  • Wind shear & gradient
  • Calibration issues
• How well and consistently you tack
  • The tack score – Distance Lost to windward (DLw). This number is used by the OS5 BET diagram which tells you whether or not to tack on shifts.
  • Steering profile
  • Sail trim
  • Acceleration
• How well you called the laylines. Especially whether you had to pinch, or worse yet, short-tack to make the mark.
• Where you went the wrong way based on what the wind and current did

Features

Chart view

The LogScanner chart view shows you where you went and what the wind and current were doing. Items include;

• The boat location and its heading
• Numerics of your choice
• Wind and current vectors (the red and blue arrows)
• Performance percentage (the red/green line)
• The amount of time gained/lost for each leg (the blue dots)

You can zoom in and out, and move the boat around the course by clicking on the chart. The stripchart remains in sync with the boat’s location.

Strip view

The stripchart view shows the variables over time. Any number of variables can be included on up to 4 strips. An important part of the strip view is the Events items. Here you see a tack event along with its analysis.

The tack analysis provides metrics of exactly what happened during the tack.

• DLw (Distance Lost to weather). This is the bottom line metric – the amount of distance to weather the tack cost.
• The true wind stats including shear and wiggle (the indicator of how good your calibration is).
• The timing marks; head to wind, the point of lowest boatspeed and highest true wind angle on the new tack (and how much), and the length of the tack.

RaceCam™

RaceCam is a video camera and processing application that records and analyzes a video of your race. There are many ways to record the video for processing, such as a GoPro or “IP” Surveillance camera.

• Having a video of your race aids in finding out why what happened happened.
• In addition to finding out what happened, having a video of your race can be useful in a protest.

LogScanner report

LogScanner produces a word document summarizing the log file and its events. Each leg’s performance summary, analyzed tacks and any added notes are listed.

Since it is a word document, you can edit it to add commentary after LogScanner produces it.

Race analysis

Since the LogScanner output is produced by a robot and not a knowledgeable human, it doesn’t include any insights. That’s your job. You can add notes to the log and they will be included in the report. Otherwise, the report is just a bunch of measurements and pictures.

The development of LogScanner is an ongoing process, and describing how it works and how to find those insights you are looking for means we will break the how-to into separate posts.

Next post…

LogScanner posts

• RaceCam video
• How to load a log file
• Getting started with analysis
• Looking at tacks
• Checking laylines
• RaceCam
• GeoGons
• LRgons
• Using LogScanner