## 4 Experiment of UA-CPGs Rolling-Gait Prototype  
To verify the applicability of the UA-CPGs oscillator control strategy in complex environments, an obstacle-crossing experiment was conducted with the snake-like robot prototype, navigating around transmission line obstacles. The control system design of the snake-like robot is shown in Figure 15, where each module corresponds to a drive motor at the joint. The CPG network is connected in a closed-loop via IIC communication. The direction of information transmission is based on the address of each MCU. The head module is equipped with a 2.4 GHz wireless communication module for receiving control signals from the upper computer. The flowchart of a single MCU is shown in Figure 16.  
The experimental snake-like robot prototype consists of 10 identical unit modules connected in series. The physical appearance of each unit is presented in Figure 17. A six-axis Inertial Measurement Unit (IMU) sensor is utilized. This sensor employs the SPI (Serial-Peripheral-Interface) communication protocol for its high-speed and straightforward data transfer to the robot's control system. To mitigate the impact of electromagnetic interference on sensor data, the wires connecting the IMU sensor are wrapped with a shielding layer. Embedded within the inner sleeve of each unit, the IMU sensor monitors the angles and speeds of both the pitching and rotating joints. This enables real-time tracking of joint  
Figure 14: Crawl speed variation of the snake-like robot. (**a**) Velocity curve of the UA-CPGs oscillators. (**b**) Velocity curve of the Hopf-CPGs oscillators. Figure 15: Schematic diagram of the snake-like robot control system. movements across the robot's body, ensuring accurate monitoring of its dynamic behavior during operation. The experimental environment is indoor, with no wind and no external interference. The diameter of the transmission cable is 50 mm, the initial winding arc \(\phi_{init}=4\pi\) rad, the initial winding deflection Angle \(\theta_{init}=58.0^{\circ}\), and the rotary joint Angle \(\phi_{init}=126^{\circ}\). The snake robot moves forward with a spiral winding rolling gait along the cable. Figure 18 shows the experimental diagram of the winding motion of the snake robot. In the experiment, the host computer generates motion control signals through the oscillator model and transmits the control commands to the servos. After receiving the instructions, the servo system executes the corresponding actions and provides feedback on the actual movement angles and speeds through the six-axis IMU sensor. During the movement, the magnetic sensors carried by the snake-like robot transmit data in real time to the control system. The system analyzes the data and continuously evaluates the current cable environment, adjusting the input parameters of the oscillators as needed. Through this adaptive control approach, the robot can precisely adjust its gait according to environmental changes, enabling smooth operation along the cable and successful obstacle crossing. Figure 16: MCU flow chat. Figure 17: Snake robot unit module entity. Figure 19a shows the angular-change curves of deflection joints 2, 6 and 10 during the winding motion of the snake robot for 5-32 s. Figure 19b shows the angular-change curves of rotary joints 2, 6 and 10 during the winding movement of the snake robot for 5-32 s. It can be found that during the movement of the snake robot, the angle of the pitching joint changes periodically, the rotating joint increases with the increase in time, and the change trend of the two joints is consistent with the simulation results in Figure 12.  
Figure 20 shows the velocity variation curve of the pitching joint 2 of the snake robot using a double-chain Hopf-CPGs oscillator and an UA-CPGs oscillator. It can be observed that the deflection joint noise control using the UA-CPGs controller is obviously better than the traditional Hopf-CPGs controller.