Espais Verds

In Parc del Guinardó we find many pines, including stone pines (Pinus pinea) and Aleppo pines (Pinus halepensis), which bear pine cones as their fruit.

Pine cones respond naturally to varying levels of humidity by opening and closing. They do this by curving their scales in a two-layer structure. The first layer is made of lignin cell walls, which provide strength and firmness. The second component is cellulose, a flexible fibre.

In high humidity, the outer cells expand towards the core, pressing on the cone to close it. Conversely, in dry atmospheric conditions, the pine cone remains open, with curved scales, so that its seeds can be dispersed by the wind.

The Technical University of Munich has drawn inspiration from the movement of pine cone scales to develop a hydraulic "actuator" that responds to the humidity in the air.

The device is formed by two layers that absorb varying amounts of liquid to regulate the mechanical properties of the system. One layer contains cellulose, and the other maintains the system's structural integrity.

The actuator can be used to facilitate smart buildings' heat exchange with the environment, thus reducing energy consumption and costs.

Actuators are devices designed to regulate or change the power of a plant or automated system. They work by converting the energy generated by air, water or electricity into a type of motor action. They can be hydraulic (liquid-based), pneumatic (air-based) or thermal (heat-based).

Nests built by wood pigeons (Columba palumbus) or collared doves (Streptopelia decaocto) can often be found in trees. They are simple and easily visible. In contrast, the nests of certain other birds, such as the goldfinch (Carduelis carduelis), the greenfinch (Carduelis chloris) or the serin (Serinus serinus), are prime examples of bioengineering.

Each species, with its own unique evolutionary history and specific needs, has developed distinct ways to assemble these temporary cradles in which they nurture and protect their young.

The Beijing National Stadium, informally known as the “Bird’s Nest” and designed by the Swiss architects Jacques Herzog and Pierre de Meuron, was the centrepiece of the 2008 Olympic Games.

The architects drew inspiration from the design of a bird’s nest to devise a steel and concrete structure mirroring the entwined branches that characterise these natural constructions. Although seemingly random, the stadium's steel beams and columns are arranged in a balanced way, echoing the apparently casual but structurally sound construction of a bird’s nest.

The structure's steel roof and façade, which are separate from the concrete framework, enhance its resemblance to a nest while providing practical benefits, which include its earthquake-proof properties. 

Parc del Guinardó is home to several bat species, such as the common pipistrelle (Pipistrellus pipistrellus) and the soprano pipistrelle (Pipistrellus pygmaeus). These animals typically wake up at dusk and come out to feed on insects. Bat boxes have been installed in some parks to attract them, as they can eat large numbers of mosquitoes.

Bats use echolocation to find prey and avoid obstacles as they fly. They do this by emitting sound signals from their mouth and nose. The sound signal travels through the air, bounces off the object in question and returns to the bat, providing it with information about its shape and location. In essence, bats use their ears to "see" the world around them, in a similar way to how ships use sonar.

A sound sensor developed by researchers at Virginia Tech uses machine learning to obtain a more precise interpretation of incoming sound waves.

The device comprises an artificial bat ear and a microphone. When it hears a sound, the ear rotates and directs the sound waves towards the microphone. The microphone is connected to a system featuring a deep neural network that is capable of learning sounds. The sensor can pinpoint noise within half a degree, with greater precision than humans, who can detect sound within seven degrees. The device can be used for both medical and surveillance/security applications.

There are many plant species with whorled leaves in Parc del Guinardó. Two of these, the oleander (Nerium oleander) and the glossy abelia (Abelia grandiflora) have a double-twisted internal structure.

In the oleander plants, you can see nearby, you'll notice a pattern of three leaves per level. This structure makes them more robust and ensures that all parts of the plant receive nourishment. Inside the branch, whose core is filled with sap and protected by bark, twists in a corkscrew shape to deliver nutrients to the leaves on every level. A cross-section of one of these branches would reveal the two geometric shapes behind this column: equilateral triangles and hexagons. The hexagons are formed by rotating an equilateral triangle in accordance with the principles of double-twist columns.

From here, you can admire the Sagrada Família. Much of Gaudí's work drew inspiration from nature. An example of this is the tree-column in the basilica, a new type of column, known as the double-twist column, devised by Gaudí himself. Its structure mirrors that of many plants, such as the oleander.

The main reasons that led Gaudí to create tree columns with branches and offshoots were those aspects of their structure. Inside the basilica, the columns are evocative of a dense forest. Gaudí wanted to create an environment conducive to contemplation and inner peace, akin to the effect of light filtering through the leaves and the spaces between the trees in a forest.

Parc del Guinardó is home to several species of dragonflies, such as the common darter (Sympetrum striolatum), which can often be seen in the dry meadows of the Mediterranean region.

Their exceptional flying skills help them catch prey and escape their predators. They can turn quickly at high speeds and take off while carrying three times their own body weight.

Their wings are made of various adaptive materials, forming a very complex composite structure that enables them to fly with great efficiency and weightlessness. They consist of various types of veins that run through a thin membrane, providing structural integrity and enhancing the durability and efficiency of flight.

The wing is arranged in a zigzag pattern in profile, with the veins vertically offset from one another. This structure allows dragonflies to make slight changes to their wing shape as they fly, increasing lift and reducing the risk of breakage.

Drones can be useful for delivering essential supplies to dangerous or hard-to-reach areas. However, they are usually big and heavy, making them slower and less nimble.

An Australian university has developed a drone that features various mechanisms to enhance flight efficiency. One notable efficiency-enhancing feature is its large, lightweight and corrugated wings, which account for less than 2% of its total weight. These lightweight wings provide maximum control and enhance precision.

Another relevant aspect is the mechanism used to operate them, i.e. how the wings are moved. Their direct actuation, i.e. the fact that the wings are directly connected, results in improved control.

From this viewpoint, we can admire the city at the edge of the Mediterranean Sea. The sea is an ecosystem teeming with life. Algae are one of the lesser-known inhabitants of the ocean floor.

Seaweed has a remarkable ability to withstand internal wave forces. This is due to its flexibility and elasticity. Its stem has a flexible joint at the base, enabling it to bend and be gently moved by the currents instead of breaking.

This structural principle has led to the development of energy-generating systems that can adapt and harness the force of the waves.

A Canadian company has developed a system of floating blades and a flexible stem to harness energy from ocean waves. This energy system features three floating blades and a stem that responds to the movement of the waves.

This movement is converted into energy through an integrated conversion module that turns the movement of the waves into hydraulic pressure, causing a turbine to rotate and produce electricity.

Most energy is derived from the combustion of fossil fuels, which emit carbon dioxide and other greenhouse gases into the atmosphere. It is imperative that we identify alternative and renewable energy sources in the next few years to mitigate the effects of climate change.

This wooded part of the park is home to a few varieties of thistles, such as the purple milk thistle (Galactites tomentosa), the creeping thistle (Cirsium arvense) and the milk thistle (Silybum marianum).

Thistle seeds are covered in tiny hooks, which help them stick to animal fur. This allows the seeds to travel long distances before germinating, helping the plant spread out over a broader area. 

A textile company has drawn inspiration from thistle seeds, which are covered in tiny hooks that help them stick to the fur of mammals.

Just like thistle seeds, Velcro consists of one surface featuring small hooks and another covered in small loops. When the two are pressed together, the hooks engage with the loops, resulting in a strong connection between the two surfaces.

Common geckos (Tarentola mauritanica) can be found on many of the park's walls and surfaces.

They are members of the gecko family (Gekkonidae) and possess unique traits that set them apart from other reptiles. One of these is their ability to cling to all kinds of surfaces, even at steep angles (including ceilings), due to the adhesive suction pads on their feet. Their toes are covered in millions of tiny hair-like projections known as setae. These setae are further subdivided into hundreds of nanostructures ending in tiny discs known as spatulae, which are responsible for their ability to stick to surfaces.

There is a new adhesive technology in the market that emulates the way geckos' tendons work to produce a strong adhesive that, unlike traditional single-use adhesives, which leave a sticky patch after removal, leaves no residue.

This technology uses the concept of draping adhesion, which mimics the skin-bone-tendon structure of geckos' feet, to create a strong yet residue-free adhesive mechanism. It is made up of two components: a soft elastomer and a rigid fabric. The material, which can vary (as this is a technology rather than a specific material), can be tailored to specific surfaces and retain a high degree of elastic rigidity.

Parc del Guinardó is home to several species of ants, such as Camponotus cruentatus, Lasius niger, Messor barbarus and Formica lemani.

Ants have networks of trails between their nests and food sources. If a trail becomes unavailable, they retrace their steps and take the next most efficient route.

Ants emit pheromones as they walk along these pathways. As they gradually evaporate, they enable other ants to find the most recently used route.

Ants resolve a fundamental computational challenge: how to maintain a network of trails and find alternative paths to reroute disrupted connections. Conventional sampling methods do not keep track of previously sampled elements. This means that the program does not remember what it has already done and may, therefore, end up repeating the process.

Stanford University has developed a search algorithm inspired by ant trail networks, which operates using behaviour-based data. Rather than having a central manager, the algorithm relies on individuals managing the system.

The algorithm effectively deals with network disruptions, uses fewer computational resources and results in greater efficiency. It could be useful for search engine optimisation.