Skip to main content

On-Board Automatic Welding for Ship Erection - Phase 2

Objective


The main results of the project are constituted of:

- A lightweight European anthropomorphic manipulator & relevant controller, the first in Europe having a mass less then 50 Kg;

- The welding system prototype and experience gained during the application in a full scale mock-up during the site trials;

- Supervisor for high level control of a complex system composed of a mobile platform, robotic arm, vision system and welding equipment;

- Vision system based on laser line properly developed for this application providing high accuracy at short distance.

The trials performed inside the cell mock-up have demonstrated the functionality of the welding system and its capability to perform welds controlling the system from outside the working cell.
The developed prototype requires few specific improvements before the application in the industrial process, related the preparation of a database of welding parameters in order to have the possibility adjust them during the execution of the cell and improving in a such a way the quality of the welds.
Objectives and content
Welding operations on the edge of blocks and sections of
a ship in the dry-dock or in the slipway during the final
erection, especially as regards the interior of the ship,
are usually carried out manually. The working conditions
for the human operators are very uncomfortable and the
related costs are high. The shipyards are strongly
motivated to automate these operations to eliminate man
presence in the confined areas inside the ship. Whereas
welding robots exist and are already used in the
workshop, they have not been employed in the drydock/slipway. The main reasons are the difficulties to
access the cells and to move inside. The development of
a mobile robotic welding system to automate this phase of
the ship construction would result in the following
benefits (addressing the recommendation of the EC DG III
Maritime Industries' R&D Master Plan on competitive
engineering in Europe):
increase in the productivity by a factor of 3.6 by
increasing the welder's arc time in confined spaces and
the deposition rate
reduction by 10% of the assembling lead time in the
dry-dock/slipway, which is the bottleneck of the ship
production process, thus resulting in an increase of the
through-put (and of market share)
better quality of weld execution thanks to the
automated process, with reduction from 20% to 10% of the
defective welds to be reworked
improvement in quality of work life of the human
operators, with positive effects on the reduction of
absenteeism provoked by working in an unhealthy
environment (confined and contaminated by smoke). A
realistic operating target is to cover all the welds in
the central part of large-medium size ships,
characterised by a more uniform cell shape.
It is proposed to develop a robotic welding system at
industrial prototype level and consisting of:
a legged mobile platform, to reposition the welding
equipment all inside the cell
a lightweight manipulator, mounted on the platform, to
perform fine positioning of the welding torch
the welding equipment including power source, torch,
wire feeder, etc
a vision system to accurately measure the workspace
(weld location and shape), prior to welding
a control console to program and supervise the system
from outside the working cell a system to perform Quality
Control (QC) of the weld from remote.
The proposed development is the second step of an ongoing BRITE-Euram project named ROWER and having scope
limited to the welding of a single type of ship cells,
those of the double bottom, and making use of a non
optimal commercial manipulator manufactured in Japan.
The partnership is well complementary, featuring a wellbalanced mix of three developers and of four end users
(shipyards). The three developing Organisations are
multi-disciplinary and complementary with respect to the
scope of the project: Tecnomare (Co-ordinator of the
project) is an Italian leading company in remote
telemanipulation systems for hostile environments; IAI,
from Spain, has a considerable experience in the design
and development of mobile platforms, control systems;
Lund University, Sweden, has been working for several
years in research on welding and related NDT. The endusers include two large shipyard companies, Fincantieri
(Italy) and Astilleros Espanoles (Spain) and two medium
shipyards, ENVC (Portugal) and Karlskronavarvet (Sweden).

Coordinator

TECNOMARE SPA - SOCIETA PER LO SVILUPPO DELLE TECNOLOGIE MARINE
Address
San Marco 3584
30124 Venezia
Italy

Participants (5)

AESA - Astilleros Españoles SA
Spain
Address
14,Ochandiano 14
28023 Madrid
CONSEJO SUPERIOR DE INVESTIGACIONES CIENTIFICAS
Spain
Address
Km 22,8,Carretera De Campo Real Km 0,200
28500 Arganda Del Rey
Estaleiros Navais de Viana do Casteo S.A.
Portugal
Address
Avenida Da Praia Norte
4901 Viana Do Castelo
Fincantieri - Cantieri Navali Italiani SpA
Italy
Address
Via Delle Industrie 18
30175 Marghera Venezia
Lund University
Sweden
Address
1,Ole Roemers Vaeg 1
221 00 Lund