Precision Guidance for Raked Pile Driving: XP300 Deployment on the MASINDRA 72

ComNav Technology · Case Study

Project Overview

The MASINDRA 72 is a 72-meter steel piling vessel operating at a port in Malaysia. It is primarily deployed for piling works of offshore terminals and near-shore marine structures.

Conventional piling operations rely on manual stakeout and operator experience, whose accuracy is susceptible to ocean waves and sea winds. When performing complex raked pile installation, this method results in time-consuming vessel positioning and a high re-driving rate of foundation piles, thus lowering operational efficiency (Fig. 1)..

The project utilized the XP300 piling guidance system to complete the installation, commissioning, and accuracy verification of the equipment on the MASINDRA 72 piling vessel. Based on high-precision GNSS positioning, IMU technology, and ComNav's proprietary algorithms, the system enables precise vessel positioning and real-time monitoring of pile location and orientation throughout operations, meeting multi-angle piling requirements.

Given  that  the operation areas are mostly offshore regions without public network coverage, a local area network was established using outdoor wireless AP to allow the bow command personnel to  monitor  operational  processes  and  progress  in  real  time  via  screen sharing on tablets . This significantly shortened the on-site operation cycle, reduced labor costs, and provided a high-precision, highly efficient digital solution for offshore pile foundation construction.

Challenges and Solutions

Project Summary

Instruments

Software

• XPiling
• Survey Master

Project Procedure

1. Set up Base Station

An  N2  receiver  is  set  up  as a  base  station  at a  control  point,  configured  with  the SNlonglink  radio  protocol  to  broadcast  RTK  differential  data  to  the   piling  vessel tablet(Fig.   2).   The   N2   receiver   integrates   a   large-capacity   battery   and  a   high- performance transceiver  radio,  ready for  immediate  use  upon  setup  and  power-on, providing a continuous, stable, long-range differential data link for offshore pile driving operations.

2. Equipment Installation

Prior to installation, our project team conducted on-site discussions with the vessel crew regarding the mounting positions of the GNSS antennas and sensors, cable routing, and operational   procedures.   The  two   GNSS   antennas   are   mounted   on   top   of   the wheelhouse; the body sensor and Tablet 1 are installed inside the wheelhouse; Tablet 2 and the AP  unit  are  installed  in  the  bow  control  room;  and  the  hammer  sensor  is mounted on the left side of the pile frame (Fig. 3).

3. Measurement and Calibration

Prior to modeling, a total station is used to survey the main antenna, slave antenna, pile frame axis, and hammer center; the modeling parameters are then derived from the measured coordinates. Key parameters include the horizontal distances from the main antenna to the pile frame pivot (L1) and to the vessel center line (L2) (Fig. 4). The pitch and roll of the body sensor and hammer sensor are also calibrated.

Calibration sequence: Antenna Position → Antenna Measurement → Body Sensor Calibration → Hammer Measurement Calibration.

4. Elevation Guidance Setup

To  achieve  real-time  comparison  between the  target  pile  point  elevation  and the elevation of the bottom marking point of the pile frame mast during the construction process, the mast extension function can be used. Measure marking point with a total station and enter the calculated mast extension value into the software(Fig. 5). The reference position can be changed later as needed.

5. Guidance Operation

During operation, the main interface displays real-time deviations between the current pile  position  and  the   target  pile  position:  forward/backward,  left/right,  elevation guidance and elevation value,  along with  heading  and  hammer  verticality  guidance value.  And  the  verticality  guidance  includes  longitudinal  raked  angle  guidance  and transverse raked angle guidance(Fig. 6).

The operator maneuvers the vessel and adjusts the pile-frame attitude until all deviations fall within tolerance and the pile-frame pitch reaches the target value. Pile driving can then begin.

Accuracy Verification

To verify positioning accuracy, four target pile positions were selected within the work area. The vessel was navigated to each target position, and the piling results were exported from the software point library. The deviations at all four points were within the project's acceptable limits. The results are summarized below.

Conclusion