Abstract: To solve some problems such as force unbalance of walking-wheels and easy to get off line existing in traditional dual-arms inspection robot walk along transmission line, the walking-wheels' force models of traditional dual-arms inspection robot and dual-arms inspection robot with flexible-cable were established respectively. Compared with traditional dual-arms inspection robot, the two walking-wheels' force of robot with flexible-cable were more balance and walking-wheel couldn't get off line with line angle increasing. Walking wheels' force conditions of two kinds of robots walking along line were simulated based on virtual prototype technology with the same parameters. Simulation results show that traditional robot would walk with single arm while line angle gradually increased to 28°, yet robot with flexible-cable still walked with two arms while line angle gradually increased to 37°. Therefore, the structural design of dual-arms inspection robot with flexible-cable has obvious advantages in walking along line, and it has stronger adaptive capacity for long-span transmission line with the bigger angle.