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Submarine gliders are specialized systems used in applications such as environmental monitoring of marine fauna, in the oil industry, among others. The glider launch and capture is a costly process that requires substantial technological and human resources, so the orderly and error-free storage of data is of fundamental importance due to the subsequent analysis. The amount of information being obtained from the seabed is increasing, this leads to the need to develop robust and low-cost ad-hocsystems for this type of application. The challenge is the integration of the different software layers in the storage system because the monitored variables must be ordered according to different glider operations such as calibration data update and navigation. Additionally, to avoid data corruption in the memory chip, error control coding must be used. The goal of this paper is to present a novel design of different layers of software integrated into a datalogger: reception, error control, and storage logic for the different glider operations. The design of the datalogger is based on a NAND flash memory chip and an MSP430 microcontroller. To correct bit-flipping errors, a BCH code that corrects 4 errors for every 255 bits is implemented into the microcontroller. The design and evaluation are performed for different glider operations, and for different lengths and correction capabilities of the BCH module. A test to calculate the storage time has been carried out. This test shows that in the case of 256 bytes per sample, at 30 samples per minute, and 1 GB of storage capacity, it is possible to collect data from the glider sensors for 84 days. The results obtained show that our device is a useful option for storing underwater sensor data due to its real-time storage, power consumption, small size, easy integration, and its reliability, where the bit error rate BER is of 2.4 ×10−11.

This paper describes the mechanical considerations, electronic architecture and the control strategies of an Autonomous Underwater Vehicle (AUV) Kay Juul H. Real time experiments for pitch and roll control are presented. The applied control technique was the sliding PID control, which main advantages are: second order sliding mode control, model free control and avoids the chattering effect. Satisfactory real time results were obtained for pitch and roll regulation. The contribution of this work is the use of the Sliding PID control in a hybrid glider, this nonlinear control technique has been used in many complex systems including underwater ROVs (Remotely Operated Vehicle).

For decades, PID (Proportional + Integral + Derivative)-like controllers have been successfully used in academia and industry for many kinds of plants. This is thanks to its simplicity and suitable performance in linear or linearized plants, and under certain conditions, in nonlinear ones. A number of PID controller gains tuning approaches have been proposed in the literature in the last decades; most of them off-line techniques. However, in those cases wherein plants are subject to continuous parametric changes or external disturbances, online gains tuning is a desirable choice. This is the case of modular underwater ROVs (Remotely Operated Vehicles) where parameters (weight, buoyancy, added mass, among others) change according to the tool it is fitted with. In practice, some amount of time is dedicated to tune the PID gains of a ROV. Once the best set of gains has been achieved the ROV is ready to work. However, when the vehicle changes its tool or it is subject to ocean currents, its performance deteriorates since the fixed set of gains is no longer valid for the new conditions. Thus, an online PID gains tuning algorithm should be implemented to overcome this problem. In this paper, an auto-tune PID-like controller based on Neural Networks (NN) is proposed. The NN plays the role of automatically estimating the suitable set of PID gains that achieves stability of the system. The NN adjusts online the controller gains that attain the smaller position tracking error. Simulation results are given considering an underactuated 6 DOF (degrees of freedom) underwater ROV. Real time experiments on an underactuated mini ROV are conducted to show the effectiveness of the proposed scheme.

In this paper we describe the mechanical and electronic design of KAY JUUL, an academic underwater glider, we also show the results from experimental tests developed in a pool. A Sliding PD Control scheme have been applied in the system, due to we don't know the parameters of the KAY JUUL yet, the control output variables were selected based on simulation results and theoretical analysis of the ROGUE, an academic glider developed by Princeton University. Satisfactory results were expected, have been achieved and are presented here.

For a long time, PID-like controllers have been successfully used in academic and industrial tasks. This is thanks to its simplicity and suitable performance in linear or linearized plants, and under certain conditions, in nonlinear ones. A number of PID controller gains tuning approaches have been proposed in the literature in the last decades; most of them off-line techniques. However, in those cases wherein plants are subject to continuous parametric changes or external disturbances, online gains tuning is a need. This is the case of modular underwater ROVs (Remotely Operated Vehicles) where parameters (weight, buoyancy, added mass, among others) change according to the tool they are fitted with. In practice, some amount of time is dedicated to tune the PID gains of a ROV. Once the best set of gains has been achieved the ROV is ready to work. However, when the vehicle changes its tool or it is subject to ocean currents, its performance deteriorates since the fixed set of gains is no longer valid for the new conditions. Thus, an online PID gains tuning algorithm should be implemented to overcome this problem. In this paper, an auto-tuned PID-like controller based on Neural Networks (NN) is proposed. The NN plays the role of automatically estimating the suitable set of PID gains that achieves stability of the system. The NN adjusts online the controller gains that attain the smaller position tracking error. Simulation results are given considering an underactuated 6 DOF (degrees of freedom) underwater ROV. Real time experiments on an underactuated mini ROV are conducted to show the effectiveness of the proposed scheme.

New technological advancements in the communication channel of time delay teleoperation systems have attracted a lot of attention, which have produced recently new control schemes, under a variety of conditions, including unknown (either constant or varying) time delay and parametric uncertainty. In this paper, a well-known model free, exact differentiator, is used to estimate the full state along with a chattering free second order sliding mode controller to guarantee robust impedance tracking under constant, but unknown, time delay of nonlinear multi-degree of freedom (n - DOF) robots. In addition, a new nominal reference is tailored in order to introduce a change of coordinates in the slave closed-loop dynamics. Experimental results, that validate the predicted behavior, are presented and discussed using the Phantom Premium 1.0 as the master robot and the Catalyst-5 virtual model as the slave robot, whose dynamics is solved online.

The response of the ROGUE underwater glider controlled by a scheme called Sliding PD control is shown and described. This control law has been widely used in robot manipulators, quadrotors and underwater ROV's. This is a model-free and chattering-free controller that makes motion robust to disturbance and uncertainty. The ROGUE dynamic model calculated on the vertical plane take into account a ballast tank fixed at the buoyancy center, a movable mass capable of motion just along the longitudinal axis and eliminates the offset static point mass. These considerations simplify significantly the equations of motion. Through simulation results this nonlinear controller demonstrates that it ensures a steady glide by directly controlling the movable mass position along with the ballast mass.

This paper was developed by the Department of Automatic Control, CINVESTAV in collaboration with the Center for engineering and Industrial Development CIDESI, Queretaro. This document involves the design and construction of a hybrid underwater Glider. The control objective is to follow a trajectory that is currently implemented by commercial gliders. The dynamic model is used to propose a control strategy based on functions of energy. The used control strategy used is an adaptive control, known as the algorithm of Slotine-Li in its Adaptive version and for the stability proof a candidate Lyapunov function was used. Finally it should be mentioned that we have results on simulation and real-time experiments. In addition the Gliders model is expressed in a matrix form.

This paper presents a dual-user teleoperation scheme to perform a collaborative task using n-DOF nonlinear manipulators as masters and slave. Impedance controllers for the manipulators are implemented in order to achieve a desired dynamic behavior depending on the user's necessities. Furthermore, a sliding mode controller is introduced to cope with the time delay in the communication channels and the uncertainty in the slave. Since the slave teleoperator is in contact with a rigid environment, the slave controller requires a free of chattering control strategy, which makes first order sliding mode teleoperation control unsuitable. Then a higher order sliding mode based impedance controller is proposed to guarantee robust impedance tracking under constant, but unknown time delay. Therefore, a position scaling factor is incorporated to deal with the different workspaces among masters and slave. The validity of the proposed control scheme is demonstrated via experimentation on a 3-DOF dual-user teleoperation system. While the haptic devices Phantom Premium 1.0A and a Phantom Omni are used as masters, a virtual industrial manipulator Catalyst-5 is used as slave. The dual-user system is tested not only in presence of constant unknown time delay in each of the communication channels but also in free and constrained motion regime.

The underwater vehicle control has two problems to deal with: parametric uncertainty and unknown disturbance. Sliding Mode Control (SMC) effectively addresses these issues and is therefore a viable choice for controlling underwater vehicles. On the other hand, this method is known to be susceptible to chatter, which is a high frequency signal induced by the switching control. In this paper a new control methodology called Model-free High Order Sliding Modes Control (HOSMC) is introduced. HOSMC principal characteristic is that it keeps the main advantages of the standard SMC, removing the chattering effects, this advantage is achieved without model knowledge. Simulation results considering the complete 6 DoF (Degrees of Freedom) hydrodynamic model of an underactuated robot, subject to ocean currents, are presented. Real time experiments of a 1 DoF underwater system are conducted to show control effectiveness.

Power line inspection and maintenance are fields of application where robotics has yet to be introduced. This paper presents the dynamic model and control of a 5 dof (degrees of freedom) dual-arm hanging robot manipulator. Prior to the construction of a prototype, it is worthwhile and necessary to model and analyze the robot performance, by means of numerical simulation, under conditions closer to reality, such as wind currents, joint and contact friction, sampling time, train gear and actuator dynamics, control strategies, among others. For the sake of simplicity, and without loss of generality, the inspection robot is considered as an open kinematics chain, wherein one of its extremities is fixed to the line and the other one is free to move. Based on the Euler-Lagrange formalism, the accomplished model is non-linear, fully actuated, and nonredundant, with rigid links and joints. Validity of the dynamic model is verified through numerical simulations by using Matlab-Simulink.

Underwater robots have had a significant contribution in the inspection, maintenance and repair of underwater structures related to the power and oil industry. Underwater robots have a big potential application in Mexico due to, the two federal Mexican companies related with the power and oil are in constant expansion. CIDESI is working in two projects (Shadow water ROV and Deep water ROV) related to visual inspection ROVs applied to the power and oil industries. Visual inspection is the essential application for a ROV, and it is used into the tasks; underwater structure inspection (dams included), underwater oil production system inspection and underwater pipeline inspection. This applied research paper firstly gives a brief instruction of the two Mexican companies related with the power and oil. Subsequently a description of the objectives and main characteristics of the developed hallow and deep water ROVs are presented and finally a general conclusions and future work is listed.

The underwater vehicle control has two problems to deal with; parametric uncertainty and unknown disturbance. Sliding Mode Control (SMC) effectively addresses these issues and is therefore a viable choice for controlling underwater vehicles. On the other hand, this method is known to be susceptible to chatter, which is a high frequency signal induced by the switching control. In this paper a new control methodology called Model-free High Order Sliding Modes Control (HOSMC) is introduced. HOSMC principal characteristic is that it keeps the main advantages of the standard SMC, removing the chattering effects, this advantage is achieved without model knowledge. Real time experiments in a 1 DOF (Degree Of Freedom) underwater system are conducted to show control effectiveness. Finally, a comparative study regarding PID control and conventional SMC is given.

This paper describes both the design and technical integration of a deep water ROV (Remotely Operated Vehicle) that is able to employ visual inspection in deep water, as well as to take samples with an underwater arm. Visual inspection is the essential application for a ROV, which is useful for; underwater structure inspection, underwater oil production systems inspection and underwater pipeline inspection. This paper mainly describes the ROV design, and explains in general manner other elements; such as the SCU, LARS and TMS. It is important to mention that the design phase is complete and it was financed by PEMEX (Federal Mexican Oil Company). The project has stalled, since we are waiting for the financial support from PEMEX for the system construction. A future objective is the design and construction of Work-Class ROVs, which can be used to perform PEMEX specific tasks.

Remotely Operated Vehicles (ROV's) have had significant contributions in the inspection, maintenance and repair of underwater structures, related to the oil industry, especially in deep waters, not easily accessible to humans. An important capability for industrial ROVs is the dynamic positioning or station-keeping (the vehicle's ability to maintain the same position with respect to the structure, at all times). It is important to remind that underwater environment is highly dynamic, presenting significant disturbances to the vehicle in the form of underwater currents, interaction with waves in shallow water applications, for instance. Additionally, the main difficulties associated with underwater control are the parametric uncertainties (as added mass, hydrodynamic coefficients, etc.). Sliding mode techniques effectively address these issues and are therefore viable choices for controlling underwater vehicles. On the other hand, these methods are known to be susceptible to chatter, which is a high frequency signal induced by control switches. In order to avoid this problem a High Order Sliding Mode Control (HOSMC) is proposed. HOSMC principal characteristic is that it keeps the main advantages of the standard SMC, removing the chattering effects. Furthermore, the proposed control is a model free control which does not require neither the dynamics nor any knowledge of the parameters, besides its exponential convergenge to the desired trajectory. From now on, the proposed controller is called sliding PD. The proposed control is verified through some numerical simulations wherein the KAXAN ROV dynamics and parameters are taken into account. The KAXAN ROV is actually under development at CIDESI, Mexico. This vehicle has a height of 0.60 m, a length of 1.1 m, a width of 0.80 m and a weight of 80 kg. Its maximum working depth is 120 meters, figure 1 shows a picture of the ROV. KAXAN in mexican Maya dialect means "the seeker".

An image processing algorithm based on the Fourier Transform Profilometry (FTP) method for 3D reconstruction purposes is presented. This method uses a global and local analysis for the phase unwrapping stage and obtains better results than using a simple unwrapping algorithm in the normal FTP method. A sinusoidal fringe pattern of known spatial frequency is firstly projected on a reference frame and an image is acquired. Then, the object of the shape to know is placed in front of the reference frame, and the same fringe pattern is projected. Once again another image is acquired. The projected pattern is distorted according to the shape of the object. Later, the modified Fourier Transform Profilometry method is applied to the acquired images. The digitized images contains the (x,y) pixels of the object including the fringe pattern, and the phase difference between the acquired images contains the z (height or depth) information. The novelty in the proposed method comes in the part of the unwrapping algorithm at the moment of obtaining the depth information by using the above mentioned combined analysis.

International audience; This paper proposes to introduce new control law algorithm based on high order sliding modes (HOSM) for dive control of the autonomous underwater vehicle (AUV) Taipan. A comparison with classical sliding mode (SM) is carried out as well. These control techniques are based on second order sliding modes. High order methods allow overcoming the chattering effect by removing the discontinuity of the control vector. We show that these high order controllers hold the properties of classical SM control laws and remove chattering problem. Another part of this paper is dedicated to compare SM vs. HOSM in Matlab simulations. These results underline the robustness of the HOSM at last.

The main purpose of this paper is to detect and follow the pipeline in sonar image. This work is performed in two steps. The first is to split a transformed line image of pipeline signal into regions of uniform texture using the gray level co-occurrence matrix method (GLCM) which is widely used in texture segmentation application. The second one addresses the unsupervised learning method based on the artificial neural networks (self-organizing map or SOM) used for determining the comparative model of pipeline from the image. To increase the performance of SOM, we propose a penalty function based on data histogram visualization for detecting the position of pipeline. After a brief review of both techniques (GLCM and SOM), we present our method and some results from several experiments on the real world data set.

International audience; The aim of this paper is to detect and follow the pipeline in sonar imagery. This work is performed in two steps. The first is to split an image (first experiment) or an transformed line image of pipeline image (second experiment) into regions of uniform texture using the Gray Level Co-occurrence Matrix Method (GLCM). The second addresses the unsupervised learning method based on the Artificial Neural Networks (Self-Organizing Map or SOM) used for determining the comparative model of pipeline from the image. To increase the performance of SOM, we propose a penalty function based on data histogram visualization for detecting the position of pipeline. After a brief review of both techniques (GLCM and SOM), we will present our methods and some results from several experiments on the real world data set

International audience; In this paper, a High Order Sliding Modes Control (HOSMC) is used to control TAIPAN, a torpedo shaped AUV from LIRMM, France. The implementation of a Second Order Sliding Mode controller in this system is the main contribution of this work. Sliding Mode Control (SMC) is adequate for controlling AUVs, since it offers robustness in the presence of uncertainties parameters and environmental disturbances, however the main drawback is the chattering effects that stimulates high frequency vibration that can damage the actuators. HOSMC control preserves the properties of standard SMC and removes the chattering effects. The design of Proportional Derived (PD), SMC and HOSMC controller for control TAIPAN depth are described. A comparative study between the control laws is presented. The nonlinear hydrodynamic model of TAIPAN is used in the numerical simulations. Simulation results, that enlighten performance of the automatic controllers are showed.

This paper describes the platform for a bilateral teleoperation where the master is a haptic device and the slave is a commercial small-sized underwater vehicle. The submarine will be instrumented, so that the electronics architecture can be upgrade at any time. With this new architecture it will be possible to program any advanced control scheme an the embedded. Also, position and velocity commands from the haptic interface to the small-sized underwater vehicle, will be send. Such that, when the force sensor, placed in the nose of the underwater vehicle, interacts with the environment, it will measure the force at the slave site and feed back it to the master robot.