Pandu Sandi Pratama

Development and controller design of wheeled-type pipe inspection robot

A wheeled-type pipe inspection robot designed to work in 300 to 500 mm diameter pipe with multiple elbows is introduced in this paper. The robot consists of two modules-active module and passive module. Each module has three wheel configurations with different mechanism to expand the wheels. A proportional integral derivative controller is designed for the robot to follow reference linear velocity and reference angular velocity. Simulations and experiments are conducted to verify performances of the proposed controlled robot. The results demonstrate that the robot with the designed controller can work well by following the reference velocity.

Experimental Comparison of A* and D* Lite Path Planning Algorithms for Differential Drive Automated Guided Vehicle

Nowadays there are some path planning algorithms for mobile robot which have been documented and explained individually in detail such as A*, LPA*, D* and D* Lite. However, there is still a lack of a comparative analysis of these algorithms. Therefore, in this paper a research of comparing A* and D* Lite algorithm for AGV’s path planning is conducted by using simulation and experiment. The goal is to compare the characteristic of each algorithm when they are applied in a real differential drive AGV and give the reader a guide in choosing algorithms for their own planning domains. The emphasis of this comparison is on the computation time of generating trajectory and the distance of the generated trajectory. The simulation and experimental results show that generally D* Lite can plan the shorter path with faster computation time than A*. However, there are some cases when D* Lite is less effective than A*. It means which of the algorithms should be chosen depends on the requirement of the system.

Trajectory Tracking Algorithm for Automatic Guided Vehicle Based on Adaptive Backstepping Control Method

This paper proposes trajectory tracking algorithm for differential drive type of Automatic Guided Vehicle (AGV) system with the unknown wheel radii using adaptive backstepping control method. To guarantee the tracking errors go to zero, backstepping control method is proposed. By choosing appropriate Lyapunov function based on its kinematic modeling, system stability is guaranteed and a control law can be obtained. In this paper, the unknown radii of left and right wheels caused by uneven load distribution or manufacturing imperfection are considered. To solve this problem, an adaptive law is proposed to estimate the changing of wheels radii. The simulation and experimental results show that the proposed controller successfully estimates the unknown parameters and tracks the reference trajectories.

Adaptive Backstepping Control Design for Trajectory Tracking of Automatic Guided Vehicles

This paper is to design an adaptive trajectory tracking controller for an Automatic Guided Vehicle (AGV) to track the desired reference trajectory with unknown slip. To do this task, the followings are done. Firstly, system description and mathematical modelings of a differential drive AGV system are presented. Kinematic model of AGV is derived based on the wheel configuration and the nonholonomic constraint. Dynamic model of AGV is obtained from the Lagrangian formula. Secondly, an adaptive backstepping trajectory tracking controller is designed. By choosing appropriate Lyapunov function based on its kinematic modeling of AGV system with unknown slip parameter stability is guaranteed, a control law and an update law to estimate the unknown slip parameter can be obtained. The simulation and experimental results show that the proposed controller successfully estimates the unknown parameters and tracks a reference trajectory.

Object following control of six-legged robot using Kinect camera.

This paper proposes a vision-based object following system for the six-legged robot using Kinect camera. To do this task, the followings are done. First, for image processing, a Kinect camera is installed on the six-legged robot. The interesting moving object is detected by a color-based object detection method. The local coordinates of the detected object are obtained to provide the position of the object. Second, the backstepping method using Lyapunov function is adopted to design a controller for the six-legged robot to achieve object following. Finally, the simulation and experimental results are presented to show the effectiveness of the proposed control method.

Path replanning and controller design for trajectory tracking of automated guided vehicles

This paper proposes D* Lite algorithm and controller design based on backstepping method for automated guided vehicles. The D* Lite algorithm is to replan a path for automated guided vehicle to avoid obstacles in the work environment such as objects that are stationary, moving, known and unknown. The designed controller is for the automated guided vehicle to track the replanned path. To do this task, the followings are done: system modeling, path replanning development and controller design. Simulations and experiments are conducted for verification of the proposed algorithm and controller. The simulation and experimental results show that the proposed algorithm and controller work well by enabling the automated guided vehicle to replan the path that passes unknown obstacle and track the planned trajectory with very small errors.

Path planning algorithm to minimize an overlapped path and turning number for an underwater mining robot

This paper considers the problem of minimizing an overlapped path and turning number to cover an uneven terrain ocean floor for an underwater mining robot. The purpose of this algorithm is to generate the shortest path to travel through the entire given bathymetric map with minimum overlapping path and minimum turning number based on binary map, cell decomposition, minimal sum of altitude method and depth-first search algorithm. To do this task, the following tasks are performed. Firstly, a binary map is obtained by applying threshold to the high slope regions of the ocean floor. Secondly, Morse cell decomposition method is applied to divide the whole area of work space into cells in the vertical and horizontal directions. To minimize the turning number, a minimal sum of altitude method is applied to the combination of vertical and horizontal cell decompositions. Finally, the coverage order is calculated by depth-first search algorithm. The simulation result shows that the proposed method generates the short coverage path with minimum overlapping, minimum turning number and fast coverage time compared to vertical and horizontal cell decomposition methods.

Walking Gait Planning Using Central Pattern Generators for Hexapod Walking Robot

This paper presents walking gait planning using a Central Pattern Generator (CPG) for a hexapod walking robot. Our CPG network model is introduced based on the Matsuoka’s neural oscillators, which is known as a neural network that generates rhythmic movements. Different output waveform can be obtained by setting the parameters of the model differently. To do this task, the followings are done. First, a CPGs network based on six Matsuoka oscillators to control the hip joint angle of the hexapod walking robot is built. Second, a mapping function to establish the relation between knee joint angle, ankle joint and hip joint is designed. Third, three kinds of gaits such as walking gait with five leg support, quadruped support gait and tripod support gait are generated by simulation. Finally, gait transition is presented by replacing the connection weight matrix of the model. Simulation results show that CPG can transition different gaits smoothly.

Fault detection algorithm for automatic guided vehicle based on multiple positioning modules.

This paper presents implementation and experimental validation of fault detection algorithm for sensors and motors of Automatic Guided Vehicle (AGV) system based on multiple positioning modules. In this paper, firstly the system description and mathematical model of differential drive AGV system are described. Then, characteristics of each positioning modules are explained. On the next step, the fault detection based on multiple positioning modules is proposed. The fault detection method uses two or more positioning systems and compares them to detect unexpected deviation effected by drift or different characteristics of each positioning systems. For fault detection algorithm, an Extended Kalman Filter (EKF) is used. EKF calculates the measurement probability distribution of the AGV position for nonlinear models driven by Gaussian noise. Using the probability distribution of innovation obtained from EKF, it is possible to test if the measured data are fit with the models. When the faults such as sensors malfunction, wheel slip or motor broken, the models will not be valid and the innovation will not be Gaussian and white. The pairwise differences between the estimated positions obtained from sensors are called as residue. Fault isolation is obtained by examining the biggest residue. Finally, to demonstrate the capability of the proposed algorithm, the algorithm is implemented on a differential drive AGV system, which uses encoder, laser scanner, and laser navigation system to obtain position information. The experimental result shows that the proposed algorithm successfully detects faults when the faults occur.

Diameter-Adjustable Controller Design of Wheel Type Pipe Inspection Robot Using Fuzzy Logic Control Method

To make the pipe-inspection robot move inside the specific dimension pipeline, the crucial problem is to adjust the diameter of the robot inside the pipeline. This paper proposes a fuzzy logic controller design method for diameter control of a wheeled-type pipe inspection robot. To do this task, the following steps are executed. Firstly, a wheeled-type pipe inspection robot that can work in 150–250 mm radius pipeline is developed. The robot is developed with two modules: active module and passive module such that each module has three wheel configurations with different mechanism to expand the wheels. Secondly, kinematic models of 4 bar linkage of the robot and dc motor are presented. Thirdly, the PI controller and the fuzzy logic controller are presented for the robot to track the given robot diameter. Finally, simulation is performed to verify the performance of two proposed control methods. The results show that the proposed fuzzy logic controller can track the reference diameter better than using PI controller.