Guest Article by Robo-dyne

Thanks to the recent innovations in electronics and mechatronics, the use of mobile robots and manipulators is becoming popular mostly in smart factories where robotic platforms are used to move heavy loads and for the storage of goods.

One of the questions that arise when developing a new mobile robot is: continuous tracks or wheels? When implementing a new industrial robotics application, it can be very difficult to correctly choose between wheels and tracks when you build a robot because each locomotion system provides different performances and outputs. The most important features to consider when you have to design a locomotion system are the traction, the driving system, for example, Ackermann or skid-steering, the maximum ground pressure and the suspension system.

If it is necessary to minimize the ground pressure, then it is necessary to choose a solution based on tracks since they are well suitable for soft surfaces. On the other side, wheels have a significant advantage in steering compared to tracks and this can be translated into a good manoeuvrability for the wheels. Robo-dyne is a robotics company that provides tracked and wheeled robots that can be customized depending on the final requirements; this is particularly useful for all that companies that need to develop high-level applications based on a mobile robotic platform and do not will to invest money and time to build the mobile base because they aim to focus on the final application.

Robo-dyne designed MaXXII-S which is the first electric mobile robot with skid-steering and rubber tracks powered by AGM Batteries and able to use an innovative undercarriage configuration which includes a large rear wheel and a couple of two smaller front idle wheels pointing forward. This configuration allows the robot to be able to keep its balance when additional tools, i.e., lawn mowers unit, weed cutter, rotary hoes, are mounted on its rear side and it can also overcome obstacles greater than the ⅔ of the diameter of the rear wheel since the upper front wheel leans on it providing area for extra grip. MaXXII-S is open source and runs with ROS and C++ libraries in order to support researchers all over the world to develop their industrial applications.

The center idle wheels provide a better pressure distribution on the ground. A passive suspension system is used to minimize the vibrations over the main frame caused by the tracks-terrain interactions. In particular, MaXXII-S adopts a set of three shock absorbers with preload adjustment in addition to the possibility to change the elastic coefficient in order to better adapt the system configuration depending on the terrain features. This electric skid-steering tracked mobile robot and its undercarriage is already available on the market finding use in a vast range of agricultural applications, such as plant monitoring or weed cutting, and also for industrial use to move goods in warehouses with uneven ground as also reported on the manufacturer’s official website robo-dyne.com.