Dirt-resistant spherical bearings in robots for weed control

• What was needed: igubal® Spherical plain bearings
• Requirements: the use in fields required spherical plain bearings that are resistant to dirt and dust as well as robust; at the same time, the customer was looking for a cost-effective and lightweight solution
• Industry: Agriculture
• Success for the customer: igubal® Spherical plain bearings are resistant to media, UV rays, radioactive radiation, dirt and dust; unlike metal rod ends, they are able to absorb vibrations; in addition, polymer spherical plain bearings are up to 80 per cent lighter than metal bearings, which also had a positive impact on energy consumption in this application

EcoRobotix develops, manufactures and distributes innovative agricultural machinery. The aim is to offer accurate, safe, reliable and affordable robotic solutions that simplify farmers' lives and produce healthy food. The start-up company's first in-house development is a weeding robot that travels autonomously across fields and destroys weeds in a targeted manner.
The robot weighs around 130 kilograms, moves independently, orientates and positions itself using GPS and a camera. An image capture system recognises whether and where the weeds are located.
The robot is equipped with an RTK GPS for exact positioning. It is fully controlled and configured using a smartphone application. And solar operation makes the robot completely self-sufficient in terms of energy supply, even when the sky is overcast.
Once the robot has identified a weed, it sprays a microdose of herbicide onto the weed with pinpoint accuracy using two robot arms. Rod ends are used to ensure that the two robot arms have the desired manoeuvrability. Because they are used in fields, they need to be protected against dirt and dust and robust. The customer was also looking for a lightweight and economical solution.

The spherical plain bearings used in the robot arm are igubal® rod ends, which are corrosion-free and can withstand temperatures from -40 to +200 degrees Celsius. They are also resistant to media, UV rays, radioactive radiation, dirt and dust. And unlike their metal counterparts, the rod ends are able to absorb vibrations. The igubal® rod ends are ideal for this application because they are lightweight, cost-effective and very robust.
Once installed, the tribo-polymer bearings require no further attention - thanks to their lubricant-free design, maintenance is no longer necessary. Unlike lubricated metal bearings, no resin or paste-like mixtures are formed that bind dirt to the bearing point. Even with extreme contamination, the plain bearings of the igubal® bearing elements do not require a seal. This applies to both fine dust and coarse dirt. Apart from this, polymer spherical plain bearings are up to 80 per cent lighter than metal bearings. In this case, twelve rod ends are fitted per robot arm, which equates to 24 such rod ends for two arms. This significantly supports the lightweight constructions and at the same time reduces energy consumption, which in this case was an important criterion for the customer due to the solar operation.