Modeling and Control of Artificial Swimming Bladder Enabled by IPMC Water Electrolysis

2018 ◽  
Author(s):  
Alicia Keow ◽  
Zheng Chen
Keyword(s):  
Pid Controller ◽  
Tap Water ◽  
Deep Ocean ◽  
Water Electrolysis ◽  
Open Loop ◽  
Metal Composite ◽  
Gas Generation ◽  
Underwater Robots ◽  
Depth Control ◽  
Buoyancy Control

Underwater robots with buoyancy control capability are highly desirable in deep ocean exploration for underwater environment monitoring and intelligent collection. In this paper, a prototype of buoyancy control device powered by ionic polymer metal composite (IPMC) is developed. An IPMC is used for enhancing the water electrolysis of tap water and separating the gases produced. The produced hydrogen and oxygen gases are stored in two separate chambers. Collection of these gases increase the volume of water displaced by the device, hence, increases its buoyancy. Two solenoid valves are used to control the release of gases to decrease the device’s buoyancy. Using a dynamic model developed in our previous work, the parameters of the model are identified through an open-loop test. A PID controller is then designed for close-loop depth control. The PID controller uses the error in depth to estimate the desired gas generation/releasing rate. It then calculates the duty cycle of the pulse-width modulation (PWM) signal used for driving the solenoid valves. The closed-loop depth control is verified both through simulation and real-time experiment, showing satisfactory results.

Buoyancy Control Device Enabled by Reversible Proton Exchange Membrane Fuel Cells for Fine Depth Control

2020 ◽  
Vol 143 (3) ◽  
Author(s):  
Jalal Yazji ◽  
Alicia Li Jen Keow ◽  
Hamza Zaidi ◽  
Luke T. Torres ◽  
Christopher Leroy ◽  
...  
Keyword(s):  
Fuel Cells ◽  
Dynamic Model ◽  
Proton Exchange Membrane ◽  
Water Electrolysis ◽  
Control Device ◽  
Proton Exchange ◽  
Underwater Robots ◽  
Neutral Buoyancy ◽  
Depth Control ◽  
Buoyancy Control

Abstract Fine buoyancy control is essential for underwater robots to maintain neutral buoyancy despite dynamic changes in environmental conditions. This paper introduces a novel buoyancy control system that uses reversible fuel cells (RFC) as a mass-to-volume engine to change the underwater robots' buoyancy. The RFC uses both the water electrolysis process and fuel cell reaction to produce and consume gases in a flexible bladder for volume change. Unlike conventional actuators such as motors and pistons used in buoyancy control, this mechanism is silent, compact, and energy-efficient. A dynamic model that described the dynamics of the RFC-enabled buoyancy change is presented. Then, a proportional-derivative (PD) controller is designed to position the device at any depth underwater. A prototype device is built to validate the dynamic model and the performance of the feedback controller. Experimental results demonstrate a fine depth control performance with 4 cm accuracy and 90 s settling time. The compact buoyancy design is readily integrable with small underwater robots for fine depth change allowing the robots to save actuation energy.

Design and control of 2-DoF joystick using MR-fluid rotary actuator

2021 ◽  
pp. 1045389X2110639
Author(s):  
Bao Tri Diep ◽  
Quoc Hung Nguyen ◽  
Thanh Danh Le
Keyword(s):  
Pid Controller ◽  
Force Feedback ◽  
Control Method ◽  
Open Loop ◽  
Friction Torque ◽  
Feedback Controls ◽  
Loop Control ◽  
Fuzzy Logic Algorithm ◽  
Experimental Apparatus ◽  
Close Loop Control

The purpose of this paper is to design a control algorithm for a 2-DoF rotary joystick model. Firstly, the structure of the joystick, which composes of two magneto-rheological fluid actuators (shorten MRFA) with optimal configuration coupled perpendicularly by the gimbal mechanism to generate the friction torque for each independent rotary movement, is introduced. The control strategy of the designed joystick is then suggested. Really, because of two independent rotary movements, it is necessary to design two corresponding controllers. Due to hysteresis and nonlinear dynamic characteristics of the MRFA, controllers based an accurate dynamic model are difficult to realize. Hence, to release this issue, the proposed controller (named self-turning fuzzy controllers-STFC) will be built through the fuzzy logic algorithm in which the parameters of controllers are learned and trained online by Levenberg-Marquardt training algorithm. Finally, an experimental apparatus will be constructed to assess the effectiveness of the force feedback controls. Herein, three experimental cases are performed to compare the control performance of open-loop and close-loop control method, where the former is done through relationship between the force at the knob and the current supplied to coil while the latter is realized based on the proposed controller and PID controller. The experimental results provide strongly the ability of the proposed controller, meaning that the STFC is robust and tracks well the desirable force with high accuracy compared with both the PID controller and the open-loop control method.

scholarly journals Electromechanical Characterization and Locomotion Control of IPMC BioMicroRobot

2013 ◽  
Vol 2013 ◽  
pp. 1-17 ◽  
Author(s):  
Martin J.-D. Otis
Keyword(s):  
Degrees Of Freedom ◽  
Three Dimensional ◽  
Water Electrolysis ◽  
Laser Vibrometer ◽  
Metal Composite ◽  
Current Consumption ◽  
Polymer Metal ◽  
Multiple Frequencies ◽  
Electromechanical Characterization

This paper presents the electromechanical characterization of Nafion-Pt microlegs for the development of an insect-like hexapod BioMicroRobot (BMR). BMR microlegs are built using quasi-cylindrical Nafion-Pt ionomeric polymer-metal composite (IPMC), which has 2.5 degrees of freedom. The specific manufacturing process using a laser excimer for one leg in three-dimensional configurations is discussed. Dynamic behavior and microleg characteristics have been measured in deionized water using a laser vibrometer. The use of the laser vibrometer shows the linear characteristics between the duty cycle of square wave input and displacement rate of the actuator at multiple frequencies. This linearity is used to design a servo-system in order to reproduce insect tripod walking. As well, BMR current consumption is an important parameter evaluated for each leg. Current passing throughout the IPMC membrane can result in water electrolysis. Four methods are explained for avoiding electrolysis. The hardware test bench for measurements is presented. The purpose of this design is to control a BMR for biomedical goals such as implantation into a human body. Experimental results for the proposed propulsion system are conclusive for this type of bioinspired BMR.

Model-Free PID Controller Based on Grey Wolf Optimizer for Hovering Autonomous Underwater Vehicle Depth Control

2020 ◽  
pp. 25-35
Author(s):  
Mohd Zaidi Mohd Tumari ◽  
Amar Faiz Zainal Abidin ◽  
Ahmad Anas Yusof ◽  
Mohd Shahrieel Mohd Aras ◽  
Nik Mohd Zaitul Akmal Mustapha ◽  
...  
Keyword(s):  
Pid Controller ◽  
Autonomous Underwater Vehicle ◽  
Underwater Vehicle ◽  
Grey Wolf Optimizer ◽  
Grey Wolf ◽  
Model Free ◽  
Depth Control

IMPROVEMENT OF QUADROTOR PERFORMANCE WITH FLIGHT CONTROL SYSTEM USING PARTICLE SWARM PROPORTIONAL-INTEGRAL-DERIVATIVE (PS-PID)

2017 ◽  
Vol 79 (6) ◽  
Author(s):  
Andi Adriansyah ◽  
Shamsudin H. M. Amin ◽  
Anwar Minarso ◽  
Eko Ihsanto
Keyword(s):  
Control System ◽  
Flight Control ◽  
Pid Controller ◽  
Rapid Development ◽  
Particle Swarm ◽  
Open Loop ◽  
Control Performance ◽  
Proportional Integral Derivative ◽  
Flight Control System ◽  
Advanced Control

The rapid development of microprocessor, electrical, sensors and advanced control technology make a quadrotor fast expansion. Unfortunately, a quadrotor is unstable and impossible to fly in fully open loop system. PID controller is one of methodology that has been proposed to control the flight control system. Unfortunately, adjustment of PID parameters for robust control performance is not easy and still problems. The paper proposed a flight controller system based on a PID controller. The PID parameters are tuned automatically using Particle Swarm Optimization (PSO). Objective of this method is to improve the flight control system performance. Several experiments have been performed. According to these experiments the proposed system able to generate optimal and reliable PID parameters for robust flight controller. The system also has 41.57 % improvement in settling time response.

Multivariable PID Controller for Unidentified Plant

1982 ◽  
Vol 104 (3) ◽  
pp. 270-274 ◽  
Author(s):  
S. Thompson
Keyword(s):  
Mathematical Model ◽  
Power Plant ◽  
Nuclear Power Plant ◽  
Pid Controller ◽  
Nuclear Power ◽  
Distillation Column ◽  
Open Loop ◽  
Pid Controllers ◽  
Simulation Studies ◽  
Plant Simulation

A procedure is presented for designing multivariable controllers for unidentified plant. It is assumed that the open-loop plant is stable and its response to step inputs are basically nonoscillatory. For such plant, no mathematical model is required in order to generate multivariable I, PI, or PID controllers. Method of tuning the controllers are also presented and demonstrated, first on a low order linear distillation column model, and finally on a high order, nonlinear, once-through boiler model typical of the type used in nuclear power plant simulation studies.

Depth Control of Underwater Robot with Metal Bellows Mechanism for Buoyancy Control Device Utilizing Phase Transition

2013 ◽  
Vol 25 (5) ◽  
pp. 795-803
Author(s):  
Koji Shibuya ◽  
◽  
Yukihiro Kishimoto ◽  
Sho Yoshii
Keyword(s):  
Phase Transition ◽  
Control Method ◽  
Control Device ◽  
Underwater Robot ◽  
Maximum Output ◽  
Depth Control ◽  
Metal Bellows ◽  
Control Devices ◽  
Target Depth ◽  
Buoyancy Control

The ultimate goal of this study is to develop a buoyancy control device that utilizes volume change due to phase transition of material between solid and liquid states. This paper describes the depth control method for an underwater robot fitted with the metal bellows buoyancy control devices that we have developed in this study. Four metal bellows buoyancy control devices are installed on an underwater robot. We first measured underwater robot buoyancy change and found that it agreed roughly with theoretical values. We then checked whether the robot could change buoyancy successively so that the robot rises or sinks as commanded. We then conducted a series of experiments on robot depth control in which if the robot depth is more than a certain distance different from the target depth, control devices are either heated or cooled at maximum output. If such a difference is within the threshold, proportional control is applied to develop output in proportion to the distance to the target depth. Experimental results showed that the underwater robot followed varied target depth with a steady-state deviation of a few cmor so, except in some cases of failure.

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