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Energy-efficient control of a screw-drive pipe robot with consideration of actuator's characteristics.

Li P, Ma S, Lyu C, Jiang X, Liu Y - Robotics Biomim (2016)

Bottom Line: Nevertheless, the energy is limited for the whole inspection task and cannot keep the inspection time too long.We also propose a velocity selection strategy that includes the actual velocity capacity of the motor, according to the velocity ratio [Formula: see text], to keep the robot working in safe region and decrease the energy dissipation.This selection strategy considers three situations of the velocity ratio [Formula: see text] and has a wide range of application.

View Article: PubMed Central - PubMed

Affiliation: School of Mechanical Engineering and Automation, Harbin Institute of Technology Shenzhen Graduate School, ShenZhen, 518055 China ; Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Shatin, Hong Kong China.

ABSTRACT

Pipe robots can perform inspection tasks to alleviate the damage caused by the pipe problems. Usually, the pipe robots carry batteries or use a power cable draining power from a vehicle that has many equipments for exploration. Nevertheless, the energy is limited for the whole inspection task and cannot keep the inspection time too long. In this paper, we use the total input energy as the cost function and a more accurate DC motor model to generate an optimal energy-efficient velocity control for a screw-drive pipe robot to make use of the limited energy in field environment. We also propose a velocity selection strategy that includes the actual velocity capacity of the motor, according to the velocity ratio [Formula: see text], to keep the robot working in safe region and decrease the energy dissipation. This selection strategy considers three situations of the velocity ratio [Formula: see text] and has a wide range of application. Simulations are conducted to compare the proposed method with the sinusoidal control and loss minimization control (minimization of copper losses of the motor), and results are discussed in this paper.

No MeSH data available.


Related in: MedlinePlus

Cruise start mode with  rad/s,  s. a Velocity comparison, b energy dissipation, c velocity constant versus velocity undulation, d energy dissipation
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Fig8: Cruise start mode with  rad/s,  s. a Velocity comparison, b energy dissipation, c velocity constant versus velocity undulation, d energy dissipation

Mentions: Figure 8 shows the results of the two methods within the same time interval to reach a same speed that the operator inputs. The velocity and energy dissipation of minimum energy control are both lower than that of loss minimization control that only considers . Figure 8c shows the two conditions after the robot reached the speed of the cruise start mode: One is that the robot keeps the velocity constant, and the other is that the robot’s speed varies (we use a sinusoidal function in this figure). Figure 8d shows that the velocity variation needs more energy to keep the robot moving than that of keeping the velocity invariable. Thus, it is better to keep the speed of the robot stable in the pipe in order to save energy in the field environments.Fig. 8


Energy-efficient control of a screw-drive pipe robot with consideration of actuator's characteristics.

Li P, Ma S, Lyu C, Jiang X, Liu Y - Robotics Biomim (2016)

Cruise start mode with  rad/s,  s. a Velocity comparison, b energy dissipation, c velocity constant versus velocity undulation, d energy dissipation
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4940445&req=5

Fig8: Cruise start mode with  rad/s,  s. a Velocity comparison, b energy dissipation, c velocity constant versus velocity undulation, d energy dissipation
Mentions: Figure 8 shows the results of the two methods within the same time interval to reach a same speed that the operator inputs. The velocity and energy dissipation of minimum energy control are both lower than that of loss minimization control that only considers . Figure 8c shows the two conditions after the robot reached the speed of the cruise start mode: One is that the robot keeps the velocity constant, and the other is that the robot’s speed varies (we use a sinusoidal function in this figure). Figure 8d shows that the velocity variation needs more energy to keep the robot moving than that of keeping the velocity invariable. Thus, it is better to keep the speed of the robot stable in the pipe in order to save energy in the field environments.Fig. 8

Bottom Line: Nevertheless, the energy is limited for the whole inspection task and cannot keep the inspection time too long.We also propose a velocity selection strategy that includes the actual velocity capacity of the motor, according to the velocity ratio [Formula: see text], to keep the robot working in safe region and decrease the energy dissipation.This selection strategy considers three situations of the velocity ratio [Formula: see text] and has a wide range of application.

View Article: PubMed Central - PubMed

Affiliation: School of Mechanical Engineering and Automation, Harbin Institute of Technology Shenzhen Graduate School, ShenZhen, 518055 China ; Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Shatin, Hong Kong China.

ABSTRACT

Pipe robots can perform inspection tasks to alleviate the damage caused by the pipe problems. Usually, the pipe robots carry batteries or use a power cable draining power from a vehicle that has many equipments for exploration. Nevertheless, the energy is limited for the whole inspection task and cannot keep the inspection time too long. In this paper, we use the total input energy as the cost function and a more accurate DC motor model to generate an optimal energy-efficient velocity control for a screw-drive pipe robot to make use of the limited energy in field environment. We also propose a velocity selection strategy that includes the actual velocity capacity of the motor, according to the velocity ratio [Formula: see text], to keep the robot working in safe region and decrease the energy dissipation. This selection strategy considers three situations of the velocity ratio [Formula: see text] and has a wide range of application. Simulations are conducted to compare the proposed method with the sinusoidal control and loss minimization control (minimization of copper losses of the motor), and results are discussed in this paper.

No MeSH data available.


Related in: MedlinePlus