Kruse Controls’ New Calibration Screens Make RTK GPS Easy to Set Up

Jay Wise of Kruse Controls has added a user-friendly series of calibration screens to the company’s dredge positioning and logging package in use by J.F. Brennan on the Fox River Remediation in Wisconsin.

The software screens allow the operator to enter dimensions and other calibration parameters of the dredge ladder and instrumentation at the beginning of the project.

RTK (real time kinematic) Global Positioning System uses signals from a GPS base station transmitter located on a known point, such as a monument or other pre-surveyed position, to a receiver on the dredge. This establishes the real time xyz location and heading of the ladder trunnion. The parameters the operator enters into the Kruse Controls software are the fixed dimensions of the ladder and calibration configurations for the analog sensors (instrumentation). The software takes all these fixed dimensions and instrumentation signals and calculates their positions and thus the position of the bottom of the cutter, and transmits the xyz coordinates of the cutter continuously to the DredgePack® software, which displays all the positions on an operator’s screen.

The new user-friendly screens are the latest improvement Wise has made on the system, which he first installed in 2006. (See “Brennan Assembles Specialized Dredges and Equipment for Fox River Remediation,” IDR, May/June 2006.) Each improvement is available to all Kruse Controls customers, and can be customized for individual dredges.

The software for the Fox River is for swinging ladder, articulated ladder dredges, which Dredging Supply Company built in 2005 for Brennan to use in that project. The articulated ladders bend two feet behind the cutter to allow the cutter to enter the material at a small angle and to dredge in water less than 20 inches deep. The swivel point where the ladder bends is called the knuckle, and Kruse Controls included this moving part in the equation for figuring the cutter position.

Kruse Controls uses Wonderware software, an off-the-shelf product widely used for HMI (human-machine interface) in the manufacturing industry. It must be coded for each application, and Kruse Controls programmed it to perform the complicated mathematics involved in calculating the position of the cutter, using the offsets from the trunnion of each of the parts. They developed the graphics by hand.

Wise enjoys this process, especially when he goes to start-ups and sees the customers and operators light up when they see the features.“I’m having a lot of fun,” he said.