New drive concepts and amazing forms of movement have always played an important role in our Bionic Learning Network. With the BionicWheelBot, a walking robot with very special properties has emerged, inspired by the cartwheeling spider.
The biological inspiration for the BionicWheelBot is the cartwheeling spider (Cebrennus rechenbergi). It lives in the Erg Chebbi desert on the edge of the Sahara. Professor Ingo Rechenberg, a bionics professor at TU Berlin, discovered it there in 2008. The cartwheeling spider can walk like other spiders. However, this spider can also propel itself forwards with a combined sequence of somersaulting and rolling on the ground.
This allows it to adapt perfectly to its environment. On level ground, it is twice as fast in its rolling mode as when walking. However, on uneven ground, it is normally better for it to take individual steps. This means that it can move safely and efficiently in the desert, where it encounters both types of terrain.
Since he discovered the spider, Prof. Rechenberg has been working on transferring its movement patterns into technology. Studies into the behavior of the spider led to the construction of various robots which can move on difficult terrain. For the BionicWheelBot, the Berlin scientist has now further developed the kinematics and the drive concept together with our bionics team.
In order to start rolling, the BionicWheelBot bends three legs each on the left and right of its body to make a wheel. The two legs that are folded in whilst walking then extend, push the rolled-up spider off the ground and continuously push it forwards as it rolls. This prevents the BionicWheelBot from grinding to a halt and ensures that it can move itself forwards even on rough terrain. Like its natural role model, the artificial spider is much faster in rolling mode than when walking. The robot can even cope with uphill gradients of up to five per cent.