Tham khảo tài liệu 'mobile robots current trends part 7', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | A Micro Mobile Robot with Suction Cups in the Abdominal Cavity for NOTES 169 According to the value of the judge function h the rotation of the stepping motors for Guide-tube L R U left right up-down wire respectively were determined. That is the robot would keep moving until h a. In the case h 0 the motor would rotate to move forward while in the case h 0 . the case that the rear suction cup goes over its target the motor would rotate to move backward. Fig. 20. An illustration for the moving forward motion in Phase 3 Fig. 21. The lift-up operation of the rear suction cup Phase 4 The purpose of Phase 4 is to adsorb the rear suction cup to the moving surface. Since when released at the end of Phase3 the rear housing with the rear suction cup would drop down by its weight there is a deflection of the wires and guide-tubes in the beginning of the Phase 170 Mobile Robots - Current Trends 4. Basically the operation that could lift the rear suction cup up to the moving surface is required. However by using Wire U only the front suction cup could be lifted up towards the moving surface as shown in Fig. 5. In this study we employed a motion shown in Fig. 21 to achieve the same effect. That is by fixing all three guide-tubes and pulling back all the Wire L R and U the deflection could be deleted or at least decreased. Certainly by this operation the front housing will receive a pulling force which would affect the adsorption of the front suction cup to the moving surface. Although the experiment results would show that the feasibility of this operation in the near future a new mechanism should be designed improve lift-up of the rear suction cup. Except the lift-up operation the other sensing and operation are just the same as the Phase 2. The effect of parameters and experiment setting-up It is clear that the two parameter Df and a would influence the behavior of the robot. The parameter a determines the accuracy of the robot. In the experiment the a was set as .