An approximate robotics algorithm to assemble a loop between two helices

We have developed an algorithm to assemble a loop in between two helices using the idea of the cyclic coordinate descent (CCD) that is an inverse kinematics approach in the field of robotics. Our method is a variant of the original CCD. It uses both the forward walk and the backward walk with different targets. A test of 20 cases suggests that the minimum root mean square deviation to native for the 500 assembled loops is comparable to that of the original CCD method but less number of the loops is needed. The results of the test suggest that the number of walks needed to reach the required accuracy can be significantly smaller than 50, the maximum number allowed in our method.