I have an application where I wish to (eventually) auto-steer a competitive waterski boat in a straight line over approx. a 1200’ distance at up to 36mph (measurement/control duration is about 23 seconds). The straight line is between 8 pairs of buoys spaced about 9’ apart over the 1200’ distance. The end objective is to assure the boat is within +/- 2 inches of the straight line through the centerline of the course. Certified waterski tournament drivers are able to do close to this today and are measured by video cameras at each end of the lake the course is in with judges watching the live video at all times (and recording it in record tournaments). The locations of the buoys are fixed and can be accurately determined (in lat/long). The speed of the boat is already controlled with a GPS based system that is repeatable to +/- 10mSec over the course length so the velocity control aspect has been removed from the human boat driver. Here we are trying to remove the human from determining the course/heading of the boat driving.
At first I plan to capture the data and display it immediately following the boat’s pass through the course (replacing the analog video system used today). Eventually a closed loop system will be employed to auto-steer the boat to keep it precisely centered and on the straight line thru the center of the course. There will always be a driver in the boat who will relinquish control to the auto-steering system for the ~23 seconds boat is in the course.
So I have been studying IMU, AHRS, GPS, and autopilot systems to get a basis for developing such a system and have some hardware (ArduIMU, GPS, etc) on order to experiment and learn more about the subject. The problem is I am having trouble “getting started” in how to take the IMU and GPS data and apply it to the measurement phase of the project. I realize that actually controlling the rudder of the boat will be a huge challenge but will tackle that once an “error” signal can be generated.
Can anyone help me get started on this by providing suggestions, information, links, and other areas of study, etc.?
Thanks!
Al
PS I searched on ‘boat’ and read every post on the subject in this forum before making this new topic post.
Replies
OOk first, even with a super duper wamadyne survey differential type gps are you going to get within your 2" tolerance. It could be technically achievable, but the systems will probably cost way more than the boat. Regular gps is around a few meters accuracy.
Your best bet would be an optical system set up on the lake shore. Still would be very hard (expensive) to do.