Developments of two novel types of underwater crawling microrobots

In this paper, in order to deal with the resistance of friction caused by rough surface of the ground in underwater condition, we designed a novel type of underwater microrobot utilizing two segments of ICPF (ionic conducting polymer film) actuators. We have carried out the experiments in two methods. Firstly, the displacement matrix in water of an ICPF actuator sample, which is same as the actuator utilized on microrobot in dimension, has been measured with different input signals. With the matrix, a speed matrix has been calculated out. To modify the matrix, the trajectory and force characteristic of ICPF actuator have been researched. Secondly, the speed matrix has also been measured on a special underwater tramroad directly. The result shows that this crawling method has a good performance on rough surface. When the signal is 1 Hz and 10V, the microrobot could arrive at a top speed of 7 mm/s on a kind of special tramroad. Compared with the two speed figures, the curves are similar in shapes, but values are not exactly the same, especially when the frequency is over 3 Hz. The phenomenon has been analyzed and another kinematics method is researched. Based on the method, another microrobot with one ICPF actuator is designed and carried out. The successor shows a good speed performance on smooth surface when the frequency is between 25 Hz and 55 Hz. The top speed on smooth plastic surface could be over 9 mm/s when the frequency is between 35 Hz and 45 Hz. And the theoretical speed model is also researched.