2nd order IK engine is based on floating based kinematic method. The algorithm includes both numerical and analytical solutions. The walking control involves inverse kinematic, and Linear Quadratic State Incremental Control.
LQSI Control
A walking pattern generation methods with ZMP-COG (zero moment point – center of gravity) constraints. Some of the researchers used a neural-networks method , a central pattern generator, or a genetic algorithm to solve ZMP-COG pattern generation problems. However, the parameters used in those methods are too many, and the procedure to learn or to search them cost too much computation time., a
pattern generator that can allow COG height change is proposed. This pattern generator is based on an optimal control method with a
state-incremental performance index. It can solve sagittal and lateral COG
patterns with arbitrarily assigned COG height and ZMP trajectories in
real-time. Thus, dynamic walking with a natural COG trajectory on
height-changing surfaces can be achieved.