Humanoid Robotics

Abstract

Humanoid Robotics is a new and challenging research field which received significant attention since 1970s and will continue to play a central role in robotics research and in many applications of the 21 century. Regardless of the application area, one of the common problem tackled in humanoid robotics is the understanding of human like information processing and the underlying mechanism of the human brain in dealing with the real world. Considerable progress have been made in humanoid research resulting in a number of humanoid robots able to move and perform well designed tasks. Over the past decade in humanoid research, an emerging spectrum of science and engineering has emerged that leads to the development of highly advanced

Many researchers have contributed to biped locomotion on dynamic modeling, control, and gait synthesis and stability analysis. Among which, dynamic modelling is the basis in the study of a bipedal walking.

In [13] a dynamic model including the both Double support phase & single support phase and double impact are developed for the five link biped robot. Lagrangian formulations are used for deriving dynamic equations of Single support phase and double support phase. To solve the multiplier in double support dynamic equations, pseudo Jacobian will be formulated due to non-square Jacobian matrix. For the dynamic of impact, both the integration method and Newtonian method are used but only the detailed derivation using the Newtonian method is presented and the results from both the method are to be compared.

A bipedal robot has mechanism of movement as a human and it has capacity to operate in environments containing different kind of obstacles. However the dynamic of biped robot are highly nonlinear, complex and unstable. It is difficult to generate a human like bipedal motion. ZMP help to synthesize the walking patterns of biped robots and demonstrate a walking motion with actual robots. The ZMP point out dynamic stability of a biped

The prototype, name RABBIT, has four independent actuators; the axis between the torso and each thigh is actuated as is the axis of each knee. The actuator have been sized so that robot speeds compare well with the capabilities of humans. Many of the technical considerations that went into the design of the robot are summarized in [16]. The principal motivations for constructing the prototype were to study modelling, determination of optimal trajectories, limit cycles, stabilization of trajectories and the transition between walking running.

Conclusion

It is possible to convert a inadmissible path into admissible by changing the pattern parameters

ZMP is practically demonstrated in WL-10RD family of robots. Since then it is used in anthropomorphic systems and its stability is studied from different prospective including mathematical.

ZMP error in the trajectory generation can be reduce by an adjustment in the height of Center of Gravity. To change the height we change the parameters in the inverted pendulum mode.

In case of un-nominal walk of the robot, effects of un-nominal motion can be studied by changing the hip parameters. To reduce the weight on the hip joint with respect to minimum energy consumption we required to keep the hip at a high