Industrial Computer Hardware


Servo terminals move a virtual ocean

August 2015 Industrial Computer Hardware

Norwegian oil company, Lundin Norway, recently presented its unique kinetic art creation at the ONS Energy Convention, the world’s largest offshore energy trade show. It comprised 529 Plexiglas tubes moving continuously together to simulate ocean waves and symbolised the constant search for oil under water off the Norwegian coast. The objective was to create a work of art that expressed the identity of Lundin Norway. This was a complex project, both artistically, mechanically and in terms of the control technology. Beckhoff supplied the control system for this engineering marvel.

The undulating virtual ocean waves were coloured from bright to saturated orange depending on the viewpoint and the density of the tubes staggered one behind the other. The multitude of overlapping translucent pipes created a moving landscape of organic, rock-like formations. If a person approached the installation, the virtual ocean landscape opened up. The tubes were driven to a safe position, allowing the viewer to ‘dive in’.

The mechanics and supporting structure consisted of a framework of 23 steel girders. Each steel girder was equipped with 23 honeycomb-shaped stainless steel housings, every one of which accommodated a Plexiglas tube, an AM8121 Beckhoff servomotor, a drive wheel and six support wheels for guidance, as well as a capacitive sensor for position compensation. A 3D depiction of an undulating sea was created based on a cleverly devised relationship between speed, tube diameter and the distance of the tubes from one another. These were implemented mechanically, with a total of 529 installed servomotors. The associated control electronics were located at both ends of the support structure and consisted of an EK1100 EtherCAT coupler and a set of I/O components. These included digital input terminals, servo terminals for controlling the servomotors and buffer capacitor terminals for stabilising the supply voltage.

A total of 10 200 connection points had to be processed, representing a challenge both mechanically and with regards to the control electronics. The compact design of the control and motion modules and the servo drives in a 12 mm terminal housing were a prerequisite for the successful technical implementation of the artistic concept.

The control system architecture encompassed three main components: the sensor and actuator level, consisting of EtherCAT terminals and specific safety sensors; the PLC level based on four C5102 industrial PCs, and the superordinate application level.

To enable the interaction between people and the kinetic sculpture, two overlapping sensor data levels were installed: a 40 m² capacitive sensor floor installed under the flooring and four K4W sensors (depth cameras) installed in each corner of the room. The higher-level control application was developed in openFrameworks. This provided a real-time model of the environment, for which a motion diagram was created to simulate the undulating movements.

The application communicated with the four IPC platforms, which also controlled the servomotors via TwinCAT ADS. Various open Frameworks add-ons were used. In addition to that the team of developers developed three new add-ons for ‘breaking the surface’. These were ofxMultipleKinect, controlling the display and alignment of several Kinect point clouds in the same co-ordinate system; ofxBeckhoffADS, facilitating the transmission of data between openFrameworks and the Beckhoff control platform; and ofxSensfloor, directing the communication and visualisation of sensfloor data in openFrameworks.

The set values of the motion diagram, which were programmed in C++, were imported into the TwinCAT NC PTP automation software via the ADS interface. In connection with the ultra-fast EtherCAT bus system and the servo terminals, the point-to-point axis positioning software calculated the position for each individual tube in a cycle time of 1 ms. An interpolating motion resulted, which the viewer perceived visually as natural undulation. If the sensors signalled a movement such as a person entering the ‘ocean’, then the axis positions of the undulation were overwritten. The position of the pipes in close proximity were adjusted to form a protective dome around the person moving around in the space. A thin metal ring attached on the inside of each tube gave a reference signal every time it passed the capitative sensor inside the drive unit. This made it easy and safe to double check and control the adjustment positioning algorithm which gave the exact position of the tube at any time.

To read the full story online visit http://motioncontrol.co.za/+beckhoff1

For more information contact Kenneth McPherson, Beckhoff Automation, +27 (0)11 795 2898, k.mcpherson@beckhoff.com, www.beckhoff.co.za



Credit(s)



Share this article:
Share via emailShare via LinkedInPrint this page

Further reading:

Tailor-made intralogistics solutions harness scalable control and drive technology
January 2020, Beckhoff Automation , System Integration & Control Systems Design
RO-BER Industrieroboter of Kamen, Germany, develops automation solutions based on area and linear gantry robots for intralogistics. These solutions, including the new Twin-Gantry robot system, are characterised ...

Read more...
Dome protects communication sticks
December 2019, Beckhoff Automation , Industrial Wireless
With the new CU8210-M001 cabinet dome, the USB port of an industrial PC can be fed out of the control cabinet and still be well protected. In this way, reliable and powerful wireless connections to the ...

Read more...
PC-based control decorates plastic lids and containers
December 2019, Beckhoff Automation , System Integration & Control Systems Design
In-mold labelling (IML) is ideally suited to meet today’s customer requirements in the plastics industry, especially in the packaging segment.

Read more...
New XTS functionality enables novel solutions in machine building
November 2019, Beckhoff Automation , Motion Control & Drives
XTS is a smart transport system of magnetically driven movers that travel along tracks consisting of motor modules and guide rails. A Beckhoff Industrial PC is able to control the movers independently ...

Read more...
Process 4.0 breakfast seminar series
November 2019, Beckhoff Automation, VEGA Controls SA , News
Beckhoff Automation recently partnered with VEGA to present another highly successful series of breakfast seminars at venues across the country, with the theme Process 4.0. Beckhoff managing director, ...

Read more...
PC-based control platform optimises water treatment product dosing
October 2019, Beckhoff Automation , System Integration & Control Systems Design
Clean water is vital in both consumer and commercial areas, including numerous industrial applications, such as mining, petroleum refining and groundwater remediation, in addition to residential applications

Read more...
Flexible communication across building and mobility applications
September 2019, Beckhoff Automation , System Integration & Control Systems Design
TwinCAT OPC UA connects research and innovation infrastructure on Empa campus.

Read more...
Process 4.0 Breakfast Seminar Series 2019
September 2019, Beckhoff Automation, VEGA Controls SA , News
Beckhoff Automation, in partnership with VEGA, are proud to present the second South African Process 4.0 Seminar for industry. The 2019 seminars are aimed at industry segments such as oil and gas production, ...

Read more...
20 years of PC control technology
August 2019, Beckhoff Automation , News
Looking back and looking forward: an interview with Hans Beckhoff, managing director, Beckhoff Automation.

Read more...
Artificial intelligence in packaging
August 2019, Beckhoff Automation , IT in Manufacturing
Beckhoff Automation’s Benjamin Bruns explains how the company has incorporated machine ­learning as a natural extension of its control platform.

Read more...