Kinematic analysis-based comparative study and development of modified Theo Jansen linkage (MTJL)

In the field of leg robotics, the Theo Jansen linkage is widely popular due to its scalable design and deterministic foot trajectory. In this article, the author has modified and analysed the Theo Jansen linkage to achieve better step height and stride length. The proposed modified Theo Jansen linkage (MTJL) consists of two ternary links and five binary links compared to the conventional Theo Jansen linkage (CTJL) which consists of twelve binary links including a crank link. In order to identify the optimized step height and stride length, several iterations are performed by varying the dimensions of the links, and each iteration is analysed for smooth foot locus trajectory, step height, and stride length to conclude the result. The iteration showing smooth foot locus trajectory, and maximum step height and stride length are selected for further study where it is compared with the CTJL and Theo Jansen linkages (JLs) developed by the other researchers. The result shows that the MTJL has a better step height and stride length compared to JLs as well as CTJL.