In order to solve the problems that the injury, hemorrhage, infection and edema of the brain tissue caused by brain electrodes implantation for aquatic animal robots, a light stimulation device and an optical control experiment method for carp robots are proposed in this paper. According to the shape of the carp skull, the device is a structure of Chinese character " 王” cut by a printed circuit board which can provide three groups of A, B and C bridge platforms for the light stimulation source. The two ends of a bridge in every group are welded with a jumper board, and the light emitting diodes (LED) are inserted into the jumper boards as the light stimulation source, and all negative poles of the jumper boards are connected to the console by the wire. A LED light can be replaced by another LED light according to the need of the wavelength of the LED light, and various combinations of the light stimulation modes can be also selected. This device was mounted on the carp robot’s head, the carp robot was placed in a water maze, and the optical control experiment method was observed to control the forward movement and steering movement of the carp robots (n = 10) under the dark light condition. The results showed that the success rates of the three groups of red light control experiments were 53%–87%, and the success rates of the three groups of blue light control experiments were 50%–80%. This study shows that the apparatus and the method are feasible.
In order to accurately implant the brain electrodes of carp robot for positioning and navigation, the three-dimensional model of brain structure and brain electrodes is to be proposed in the study. In this study, the tungsten electrodes were implanted into the cerebellum of a carp with the aid of brain stereotaxic instrument. The brain motor areas were found and their three-dimensional coordinate values were obtained by the aquatic electricity stimulation experiments and the underwater control experiments. The carp brain and the brain electrodes were imaged by 3.0 T magnetic resonance imaging instrument, and the three-dimensional reconstruction of carp brain and brain electrodes was carried out by the 3D-DOCTOR software and the Mimics software. The results showed that the brain motor areas and their coordinate values were accurate. The relative spatial position relationships between brain electrodes and brain tissue, brain tissue and skull surface could be observed by the three-dimensional reconstruction map of brain tissue and brain electrodes which reconstructed the three-dimensional structure of brain. The anatomical position of the three-dimensional reconstructed brain tissue in magnetic resonance image and the relationship between brain tissue and skull surface could be observed through the three-dimensional reconstruction comprehensive display map of brain tissue. The three-dimensional reconstruction model in this study can provide a navigation tool for brain electrodes implantation.
In order to study the effect of light with different wavelengths on the motion behavior of carp robots, phototaxis experiment, anatomical experiment, light control experiment and speed measurement experiment were carried out in this study. Blue, green, yellow and red light with different wavelength were used to conduct phototaxis experiments on carp to observe their movement behavior. By dissecting the skull bones of the carp to determine the appropriate location to carry the light control device, we independently developed a light control carrying device which was suitable for any illumination intensity environment. The experiment of the light-controlled carp robots was carried out. The motion behavior of the carp robot was checked by using computer binocular stereo vision technology. The motion trajectory of the carp robot was tracked and obtained by applying kernel correlation filter (KCF) algorithm. The motion velocity of the carp robot at different wavelengths was calculated according to their motion trajectory. The results showed that carps’ sensitivity to different light changed from strong to weak in the order of blue, red, yellow and green, so that using light with different wavelengths to control the speed of the carp robot has certain laws to follow. A new method to avoid brain damage in carp robots control can be provided in this study.