Fundamental Study On The Artificial Induction For Gekko Gecko's Locomotion

The motion ability of a modern mobile robot system in an un-structured environment lags far behind animals in stability, flexibility, robust, environmental adaptation and efficiency of energy sources. So, biological robotics, which is to modulate animal's locomotion and makes it like a robot, has become a new attractive direction in robotics researches.Animals have wonderful locomotion abilities, especially those that can move on three-dimensional, complex terrain. The remarkable motion capability of geckos has made them the hot spot for research. The lizard Gekko gecko, natively lived in south-west of China, such as Guangxi and Yunnan province, was chosen as the target animal and was studied for developing a bio-robot, because of its excellent locomotion abilities, higher load-carrying abilities. If we can modulate gekkos'locomotion just like the robo-rats, it will be a revolution of Three Dimensional Obstacle-Free (TDOF) robots!However, few literatures concerning the locomotion mechanism of this lizard have been found. Most research on gekko has been on its forebrain, especially the neuroanatomical functions. In order to reach our target, we must understand the brain structures of the Gekko's locomotion-related brain nucleus, their spatial distribution and the space-time patterns of their electroneurographic signals.In this study, we first introduced a stereotaxic method and developed an apparatus suitable for Gekko gecko. The allocation and operation of the head holder is accurate and simple, and the device is low in cost and compatible with standard stereotaxic instrument. Based on the stereotaxic technology established for geckos, we studied the key technology for making gekko's brain atlas, and applied the electrical stimulation to the lightly anesthetized gecko's middle brain to locate the motor nucleus in its brain. Our acute experimental results showed the most effective points of stimulation for induced locomotion were located at the midbrain tegmentum near the midline, suggesting gecko's midbrain is responsible for its locomotion. In the following awake studies, we delivered electrical stimulation through implanted electrodes at the certain regions of the gecko's midbrain, and successfully elicited its some basic motor patterns, such as turning right and left, and crawling forward et al. Further more, the horseradish peroxidase (HRP) method and chemical stimulation were used to studying the cytoarchitectonics in geko's midbrain. Similarly, the results suggested that the midbrain of gecko plays a key role in gekko's locomotor modulation.In short, the stereotaxic method and the designed head holder have established a fundamental work for gekko's brain research, and the research on gecko'midbrain enriched our understanding of its brain functions on locomotion modulation, and provided important information for artificial induction on gecko's locomotion.