Public initiatives like ‘Connected Industry 4.0’ are developing measures that allow the industrial fabric to benefit from the intensive use of ICT in all areas of its activity. These initiatives are linked to the term Industry 4.0, which refers to the challenge of carrying out the 4th Industrial Revolution through the transformation of industrial sector by the enabling technologies incorporation: 3D printing, robotization, sensors and embedded systems, augmented reality, artificial vision, predictive maintenance, cybersecurity, traceability, big data, etc.
Construction sector, as the industrial one, is immersed in a deep metamorphosis before the irruption of these new technologies. The economic crisis has been very intense in this market. As a strategy for its recovery, it must its particular revolution, taking full advantage of the opportunities offered by enabling technologies. For this reason, the ‘Construction 4.0’ concept appears as a necessity to digitize the construction through the incorporation of enabling technologies adapted to their particularities.
In this sector, it is the first time that a revolution is built ‘a priori’, which gives us the opportunity both to companies and to research centres to participate actively in the future.
In CARTIF, we work along this line by means of some projects that apply these technologies. In the case of the BIM (Building Information Modeling), which proposes to manage the complete cycle of the project through a digital 3D model, we develop improvements to include all the actor of the value chain.
With reference to 3D printing, a methodology that allows the construction of objects layer by layer, obtaining singular pieces or with complex geometries, CARTIF applies technologies to the direct printing on vertical surfaces for the rehabilitation of facades.
If we talk about robotization, besides the fact that making specific robots to certain tasks, adapt existing machines increasing their autonomy and safety of operators. In this line, we collaborate to develop monitoring and navigation technologies for the automatic guidance of machinery and to detect risks situations between machinery and operators.
With all these innovations, the future of construction is promising, if and when this research would be considered as an essential basis for its growth.
To a large extent, when driving on the road, our safety depends on the state of the pavement. Real-time information provided by embedded sensors can help us to take action before deterioration (risk) occurs. What can we do to power these autonomous sensors? Piezoelectric devices vs. wireless power transmission?
The fundamental objective of road pavement is to provide users with a quality service that meets their mobility needs during the lifetime for which it is designed. A situation of deterioration generates a greater risk of an accident, more driving discomfort, fuel consumption, vehicle deterioration, harmful emissions to the atmosphere…
In May 2016, the Spanish Road Association (AEC) published the report “Study on Conservation Investment Needs” to review the state of the Spanish road network. The report notes that the state of maintenance of roads continues to worsen. If this trend continues, before 2020 it will be necessary to rebuild a good part of the network.
I agree with the experts that the conservation of our roads cannot be left to chance: nor to depend on crisis situations that force the budget to be reduced or to wait for irreversible situations.
In these circumstances, it is necessary to continue developing new technologies and methodologies that support the management of infrastructures and that allow conserving and rehabilitating our road network at the lowest economic and environmental cost.
Instrumentation with sensors embedded in the pavement
Traffic and environment/weather conditions, aggravated by climate change problems, significantly affect the pave roads deterioration.
The number of axles, the load per axis, the vehicles speed…, affect the structural behavior of the pavement. Solar radiation, rainfall, thermal gradients, ice-melt cycles, melting salts used against ice or the spillage of oils and fuels, among other factors, have a significant impact on pavement life and fatigue.
Preventive maintenance is necessary based on information on the state of the pavement and aimed to prevent the occurrence of this deterioration or to correct it quickly through repair and maintenance.
Visual inspection and periodic auscultation are commonly used to assess the condition of a pavement. A dynamic alternative is the instrumentation with sensors embedded in the pavement. With continuous monitoring it is intended that those who make decisions can know, in real time, the status of the pavement.
Experiences such as those of the CENIT OASIS project, in which we collaborate with OHL Concesiones and GEOCISA, endorse this alternative, not without difficulties such as that the sensors overcome the aggressive conditions during the spread and the compaction, or feed the sensors along the lifetime of an asphalt pavement that is normally between 20 and 30 years.
In this second aspect, since wired power is not always available or to overcome the problems of wiring flexibility, a significant technological challenge is to embed autonomous sensors in the pavement with non-wired power supply and wireless communication. How to provide energy to the sensors without cables and during the lifetime of the pavement?
Piezoelectric devices vs. wireless power transmission?
Opposite to batteries power supply, which have a limited energy, requires a periodic replacement or recharge, the sensors can be powered with energy captured from the road itself, for example by means of piezoelectric devices.
At the end of the 19th century, Pierre and his brother Jacques Curie discover the piezoelectric effect, a phenomenon that occurs in certain crystals that when subjected to pressure or mechanical movement, electrical energy is generated. On the road, part of the vehicle’s energy is converted into vertical deformation of the pavement that can be transformed into electrical energy by piezoelectric devices. The amount of energy generated depends on the number of vehicles passing.
In the CIEN REPARA 2.0 project we have choosed another method, investigating, in collaboration with Sacyr Construcción, Acciona Infraestructuras, Repsol, Fractalia, CHM, Censo, Solid Forest and Inzamac, the recharge of the autonomous sensors batteries by mean of wireless power transmission.
Also at the end of the 19th century, Nikola Tesla proposed what is known as “Tesla effect”, variations in magnetic flux have the ability to transmit electricity at a distance without needing solid support or some kind of wire. On the road, the batteries of the sensors will be recharged periodically, according to their power needs (mainly defined by the data transmission). Energy transfer has a limited range.
Actually, the efficiency of both technologies is a critical point.
Curie vs. Tesla? Indeed, confronting these technologies (using “versus” with the meaning of “against”) is not a lucky expression. Both technologies open up a world of opportunities for new applications. Are they also complementary? Which is your opinion?
In July 2015 we were surprised by the news that a robot kills factory worker after picking him up and crushing him against a metal plate at Volkswagen plant in Baunatal (Germany). They insisted the death was a result of human error and not any malfunction on the part of the robot. A Volkswagen spokesman stressed that “the robot was not one of the new generation of lightweight collaborative robots that work side-by-side with workers on the production line and forgo safety cages”.
The application of robots in industrial processes is widespread in industry (mainly automotive), where they perform a multitude of tasks, mostly sequential, repetitive and at high speed. Accidents caused by robots are highly unusual. Many robot accidents do not occur under normal operating conditions but, instead during programming, maintenance, repair, testing, setup, or adjustment. During many of these operations the operator, programmer, or corrective maintenance worker may temporarily be within the robot’s working envelope where unintended operations could result in injuries. During normal operation, robots are confined in safety cages precisely to prevent incidents in contact with humans.
Without adequate safety measures traditional industrial robots can cause serious accidents to people by crushing and trapping (occur when a worker’s limb or other body part can be trapped between a robot’s arm and other peripheral equipment, or the worker may be physically driven into and crushed by other peripheral equipment; it can be deadly, as in the case of Baunatal), collision or impact (occur when a robot’s movements become unpredictable and a worker is struck by the robot) or by projection of materials (occur when parts of the robot , tool or product handled, breaks and fly off and hits a worker).
By rules applicable throughout the EU, it has been mandatory to provide a sufficiently large security perimeter to the entire workspace of the industrial robot that prevents access to the robot when in operation. When it will be necessary to enter to this area, the worker must perform some action to stop the robot, facilitating the access. Harmonised standards ISO 10218-1 and ISO 10218-2, “Safety requirements for industrial robots”, contain the minimum requirements for safe operation of these industrial robots.
This “separation” between workers and robots in an industrial environment is weakened through collaborative robots already available on the market (Universal Robots family of robots, ABB’s YuMi, KUKA’s LBR iiwa…) and the new technical specification ISO/TS 15066:2016, “Collaborative Robots”, that specifies the safety requirements for collaborative industrial robot systems and the work environment. The standard describes different concepts of collaboration and requirements needed to achieve them. The ISO standard also points out that the collaborative operation is a developing field and the new technical specification is likely to evolve in future editions.
Collaborative robots are designed to operate in a shared workspacewith workers without the need for conventional protections, safety cages or safety barriers. The main premise in the design of these robots is the safety of workers (Asimov’s first law of robotics: “a robot will not harm a human being”). These robots are designed to work side by side with workers.
The proximity of workers and robots requires a great safety design based on a combination of mechanical design and control measures, both the manipulator and the workspace. So rather than talking about collaborative robots, in CARTIF we prefer to speak of safe collaboration spaces (collaborative spaces). Besides the robot is safe, so it is the applications and working environments.
To ensure safety can be used different technologies and security measures. Lightweight manipulatorswithout shearing or cutting points, with rounded geometries, smooth surfaces and deformable or elastic components. Speed, acceleration and power can be limited. Current, force, torque sensors can be integrated to detect collisions. Real-time movement of the robot can be adjusted with proximity and tactile sensors. In order to be “aware of the collaborative space” it can be added visual systems based on 2D/3D computer vision technologies.
Usually, collaborative robots are similar to traditional industrial robots but smaller, lighter, less fast and powerful, cheaper and easier to install and configure. These robots do not need to be fast or powerful as they are specially designed to interact with workers. As experts say, in a collaborative space, the worker can bring skills, flexibility and, above all, ability to identify, understand and solve problems, and the robot provides repeatability, accuracy and endurance. Nevertheless, the ISO/TS 15066:2016 standard does not limit the capabilities of the robot in collaborative applications.