Drives & Controls July / August 2022

38 n TRANSPORTATION July/August 2022 www.drivesncontrols.com All-plastic bike will need no maintenance A t the recent Hannover Messe, igus unveiled what it claims is the world's first urban bicycle made entirely from recycled plastics – from the frame, to the bearings and the toothed belt. Commercial models are due to go on sale by the end of the year including a version made mainly of recycled plastics that were originally intended to be used once. As well as being environmentally friendly, igus claims that these bikes will also be easier to own than others. They can be left outdoors in any weather and cleaned in seconds using a garden hose. “As all components are made of plastic, no part of the bike rusts, even the gears,” points out igus’ CEO, Frank Blase. Every part of the bike is made from lightweight, lubrication-free high- performance plastics – from the two- component ball bearings in the wheels, to the plain bearings in the seat post, brake levers and pedals. All have solid lubricants built in and ensure dry, low-friction operation, without any lubricating oil. Sand, dust and dirt cannot accumulate. Blasé first had the idea for the bicycle – known as the igus:bike – during a beach holiday. Talking to employees of a bicycle rental company, he discovered a major problem with beach bikes. Because they are exposed continuously to sand, wind and saltwater, they may last only three months before needing to be replaced. Their maintenance and replacement can be expensive and time-consuming. A team of engineers in igus’ laboratories has been working on the components in cooperation with a Dutch bicycle start-up, MTRL. Proven igus technologies have been adapted for the new application. MTRL has already put 400 plastic-framed bicycles with plastic frames and wheels onto Dutch roads. It will start production and sale of a child version of new plastic bike, as well as an adult bicycle for cities, by the end of this year. Other versions, such as an e-bike, are planned. The first prototype frames and wheels were made from old fishing nets. In the future, the all-plastic bicycles will be available made either from new plastics at a price of around €1,200, or entirely from recycled materials for about €200 more. MTRL is planning to set up manufacturing facilities near landfill site around the world. igus does not plan to produce bicycles itself but to sell components to bike-makers around the world. It has set up an online platform that will offer bicycle manufacturers the opportunity to advance the technology together. The site will show the status and progress of all components and invite players to participate. “We want to enable the bicycle industry to produce plastic bikes,” says Blase. The platform is intended to become a contact point for manufacturers who want to build a plastic bicycle and for all manufacturers of suitable components, such as plastic frames, wheels, drives, and pinions. The platform is already hosting initial corporate collaborations. One example is Helix.eco for recycled plastics. Many more will follow. “We have lots more ideas, such as installing condition monitoring using igus smart plastics,”Blase adds.“That would let you use your smartphone to see how many more thousands of kilometres the bike can take. That will hopefully convince many people who are still sceptical about plastic. The engineering plastic specialist igus has developed an all-plastic bicycle which can be made from recycled plastics. As well as being environmentally friendly, the rust-free bike can left outdoors and cleaned easily using a garden hose. Igus contends that its robust, durable urban bike is the first to be made entirely of plastic Key components Each of the components needed to create an all- plastic bike posed its own challenges. For example, the idea of bicycle gears made of plastic was regarded as being unthinkable for a long time.“We have made the impossible possible and developed an all-plastic planetary gearbox with a high efficiency,”says igus CEO, Frank Blase. The two- speed gearbox is based, in part, on technologies that igus developed for the joints in its ReBeL cobot kits. It has few components, is maintenance-free, durable, lightweight and quiet. As with other components, solid lubricants are built in. Designing a freewheel made entirely of plastic was another challenge because these components need to be extremely stable, as well as fully movable. Integrated solid lubricants reduce maintenance compared to conventional bicycles, where freewheels need to be relubricated continuously. The metal-free wheel bearings contain lubricant- and maintenance-free xiros plastic ball bearings, which are wear-resistant, resilient and quiet. Bicycles place heavy demand on their cranks which have to absorb all of the force that the cyclist applies to the pedals. The plastic bike’s lightweight crank is corrosion-resistant. The rimbrake mechanisms are made entirely of plastic and are compatible with standard brake pads. In addition to the items developed by igus, the bike uses 100% plastic frame and wheels from MRTL. Each frame will contain a“material passport” chip, allowing it to be bought back at the end of its life a turned into new frames and wheels. Instead of high-maintenance bicycle chains, the plastic bikes will be propelled using carbon- reinforced belts , developed by Gates, which never need lubrication and are almost maintenance-free.