Optical distance sensor for moving heavy loads

  • Im letzten Bauabschnitt wird ein Brü-ckensegment verschoben (Quelle: Syrinx Industrial Electronics, www.syrinx.nl)

  • Die Bauarbeiten finden in 50 m Höhe statt (Quelle: Syrinx Industrial Electronics, www.syrinx.nl)

  • Das Laser-Distanzmessgerät ODSL 30 überzeugt durch sein integriertes Display (Quelle: Leuze electronic)

  • Die großen Reichweiten stellen besondere Anforderungen an die Applikation (Quelle: Syrinx Industrial Electronics, www.syrinx.nl)

  • Die Montageplatte mit dem Sensor wird mit Magnet angebracht und ausgerichtet (Quelle: Syrinx Industrial Electronics, www.syrinx.nl)

  • Hydraulische Elemente verschieben die Brückenteile (Quelle: Syrinx Industrial Electronics, www.syrinx.nl)

  • Die Distanzen bei der Brückenbewegung werden vom ODSL 96B erfasst (Quelle: Syrinx Industrial Electronics, www.syrinx.nl)

  • Schnittstelle zum Notebook: die Messbox, an der alle Sensoren angeschlossen werden können (Quelle: Syrinx Industrial Electronics, www.syrinx.nl)

  • Syrinx Industrial Electronics hat sich um die gesamte Visualisierung gekümmert (Quelle: Syrinx Industrial Electronics, www.syrinx.nl)

Moving bridges with Leuze electronic

ODSL laser sensors measure distances as the Oakland Bay Bridge is moved within the scope of an extensive repair

Leuze electronic BV of Waardenburg (Netherlands) and Syrinx Industrial Electronics, also of the Netherlands, play an important role in the construction of the Bay Bridge in San Francisco in the U.S. state of California.

The Oakland Bay Bridge connects Oakland and San Francisco. Every day, 300,000 vehicles travel over this important, five-lane, double-deck toll bridge. Following the severe earthquake in San Francisco in 1989, it was decided to replace part of the link between Oakland and San Francisco with a new bridge. To realize this connection, it was necessary to temporarily move part of the old, existing bridge (expected to be completed by 2013) in order to make space for the construction of the new bridge.

The final construction step in the realization of this detour was the separation of a 100 m long, 3200-ton section and the subsequent moving of this section of the bridge (Figure 1). Afterward, a new, 3600-ton bridge section was pushed into the resulting gap to complete the detour section—all at a height of 50 m (Figure 2). This work was performed on Labor Day weekend in 2009 and had to be completed within three days.

In the spring of 2009, Syrinx Industrial Electronics was contracted by Mammoet, the well-known Dutch specialist for transport and assembly solutions in the heavy-load sector, to develop a central monitoring system for this project. The system was to allow all movements to be displayed on a large, 42-inch screen as the bridge parts were moved.

Decision for laser distance sensors from Leuze electronic

A total of 31 laser distance sensors and 16 pressure sensors were used. For the monitoring of this challenging project, Syrinx Industrial Electronics chose the ODSL laser distance sensors from Leuze electronic. Decisive here was their precision, robust design and the display on the ODSL 30, which allows measurement values to be read on the spot (Figure 3). As a result, it was not necessary to constantly run back to the central laptop to make adjustments during installation. Considering the large distances (Figure 4), this saved considerable time. Affixed to a mounting plate, the Leuze electronic sensors could be easily applied and positioned through the use of strong magnets (Figure 5).

Measurement of both small and large distances while moving the bridge

During the move, the bridge was pushed upward at four points approximately 30 cm and then moved laterally by means of hydraulic winches with a stroke of 1.5 m (Figure 6). The height and position of the various hydraulic winches were converted to 4 to 20 mA measurement signals with the aid of the Leuze electronic ODSL 96B laser distance sensors (Figure 7).

The horizontal movement was over a distance of approx. 30 m and was measured with Leuze ODSL 30 laser distance sensors. This model was chosen on account of its RS485 output. Syrinx Industrial Electronics constructed a converter box for this output to convert the RS485 information to an exact, 16-bit analog signal of 4 to 20 mA. In this way, it was possible to attain even greater precision over the entire measurement range up to 50 m.

In addition to the converter boxes, Syrinx Industrial Electronics also developed eight measurement boxes to which all laser distance sensors and the used pressure sensors could be connected (Figure 8). Together, all of the measurement boxes formed the complete measurement network that was connected to the laptop. The laptop was then connected to the 42-inch monitor, on which the processes could be visualized, as Syrinx Industrial Electronics also programmed a solution for the complete visualization for this project (Figure 9).

Toegepaste producten

  • Branche/vakgebied

    Building/transportation industry

  • Taakomschrijving


  • Applicatie

    Optical distance sensor for moving heavy loads