Materials for soft and bio-inspired robotics can be completely sustainable, according to a review published in Advanced Materials in 2020. The researchers argue that all robot components can be made out of sustainable materials, including actuators, energy storage, and electronics.
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Electronic and robotic appliances are becoming ever more integrated into daily life. Digital and biological spheres – once mediated through programming languages and graphic user interfaces (GUIs) – are more closely connected than they ever have been before, and this union is still getting stronger.
But the benefits of increased integration with robotics and digital technology come at the cost of our worldwide sustainability goals.
Robotic and electronic technology increases energy demands, contributing to greenhouse gas emissions and energy insecurity.
Devices also often require rare-earth metals and minerals that cause significant environmental damage when they are extracted and processed – not to mention the social impact of metal and mineral extraction operations in unstable and poor regions.
Finally, improper disposal of robotic and electronic devices pollutes the environment with materials that often take thousands of years to degrade, sometimes emitting toxic substances throughout that process.
But soft, bio-inspired robotics and electronics – which are designed to mirror performance and capabilities found in natural systems – can also mirror natural organisms in terms of their ecological footprint.
Microbots working in biohybrid machines in living organisms and actuators that are resilient yet entirely biodegradable are just a few examples of bio-inspired robotics that could transform our relationship with technology and our environment in decades to come.
The World Demands a Circular Economy
Sustainable robotics will largely depend on the success of the circular economy movement currently sweeping through manufacturing, logistics, retail, and waste management around the world.
Disposable electronic devices make up a sharply rising percentage of landfill waste, currently representing about 100,000 tons of waste every day. Consumer electronics and appliances are generally sent to landfills when they reach their end of life due to the variety of product designs and material compositions that make recycling prohibitively tricky.
When these devices are in landfill sites, the rare and often toxic materials used to manufacture them create an additional environmental threat.
Closing this linear economy model (from material extraction to production, retail, consumer use, and finally to a landfill site) into a circular loop will rely on easy to recycle design for new devices, low-cost materials that can be reused, and biodegradable or transient systems.
Bionic engineering takes inspiration from the natural world and applies it to new artificial devices, systems, and processes. In the world of robotics, bionic engineering is currently a focus of considerable research.
Natural systems can inspire safer human-machine interactions, swarm intelligence and movement, and untethered autonomous operation. In nature, a diverse range of solutions to these problems exists – which can all be mined for engineering ideas in the next generation of robots.
Soft, lightweight robot forms already replicate animals’ efficient energy management and fluent movement through space. In the future, this kind of design will be applied to materials and end-of-life cycle considerations in robotics development.
Examples of this new approach to design include soft healthcare machines designed to help elderly people with their daily functions. Robots used to harvest crops could then become compost in the field where they worked, recycling the energy in their materials for more calories next season.
Transient behavior already exists as well. Elastic pneumatic actuators, wound patching millibots that work in living organisms, drug delivery swarms of nanobots, and small gripper robots controlled by engineered muscle tissue are all examples of robotic systems inspired by natural transience.
This means their components and materials can be reabsorbed into living organisms like the human body once their tasks are complete. Devices using this technology are mostly employed in the biomedical sector, although sustainable energy storage also develops and exploits transience in synthetic materials.
The Question of Sufficiency
The paper touches on the question of sufficiency in sustainability projects. Rather than maximizing efficiency, manufacturers, builders, and developers should instead ask if new products or activities are sufficient: are they necessary?
Suppose the benefits of new products or systems outweigh the environmental costs of developing and producing them. In that case, sufficiency still has a role to play in ensuring as little harm is caused to the environment as possible.
Minimizing material requirements for new technology is a key engineering challenge but can be highly impactful on the sustainability of new technologies. Lightweight materials, compact designs, additive rather than subtractive manufacturing processes, and systems optimized to minimize waste contribute to reducing the total environmental impact of new products.
This change may already be in the making, with so-called “avoided carbon” beginning to emerge as an alternative concept to “embodied carbon” in carbon credit schemes and sustainable development guidelines.
But really emphasizing the question of sufficiency requires a radical change to the worldwide economy that would prioritize sustainability and collective good over individual profits.
Learn more about the role robotics can play in tackling climate change here.
References and Further Reading
Awere, E. et al. (2020). E-waste recycling and public exposure to organic compounds in developing countries: a review of recycling practices and toxicity levels in Ghana. Environmental Technology Reviews. Available at: https://doi.org/10.1080/21622515.2020.1714749.
Hartmann, F., M. Baumgartner, and M. Kaltenbrunner (2020). Becoming Sustainable, The New Frontier in Soft Robotics. Advanced Materials. Available at: https://doi.org/10.1002/adma.202004413.
Yang, G-Z., et al. (2018). The grand challenges of Science Robotics. Science Robotics. Available at: https://doi.org/10.1126/scirobotics.aar7650.