Modeling and control of the three degrees-of-freedom parallel manipulated robotic sensor head

Download

index.pdf

Date

2014

Author

Öğücü, Muhammed Orkun

Metadata

Show full item record

Item Usage Stats

259
views

443
downloads

Legged robot platforms have distinct advantages over wheels in rough terrain and provide better mobility. Also in many applications, including military reconnaissance, disaster relief, hazardous site inspection, search and rescue applications benefit from the legged robots which is capable of moving safely at high speeds through rough natural terrain. However, with the increasing speed, fundamental difficulties like dynamic and mechanical limitations as well as control and computational limitations arise. Also sensor uncertainty and limited terrain data can result in unexpected and dangerous situations. At such situations, the data obtained by a single sensor may not be reliable. To provide certain and robust information, it is conventional that to integrate multiple sensor data which is known as sensor fusion. Gyroscopes and accelerometers are frequently used motion sensors at robotic applications. However, these sensors can only provide an accurate solution for a short period of time because of integration drift. To correct these bias errors, cameras are frequently used in robotics applications with integration of accelerometer and gyro data. However, vision sensors are considerably sensitive to shocks and instantaneous movements especially at high speed and accelerations resulted with motion blur effect. Due to the limited performance of deblurring methods, it is crucial to avoid the captured images affecting from visual disturbances. In this thesis, head stabilization problem of SensoRHex mobile robot platform which is dynamically stable autonomous hexapod robot with six compliant legs will be examined. Thesis works can be categorized into two groups; Sensing and Control. Accelerometer and gyroscope data will be integrated with camera data according to the sensor fusion algorithms. These sensory data will be used to estimate state space vector partially. At the final stage of the sensing works is disturbance and signal characterization. Control strategy will be determined after the examination of disturbance characteristics. But there are intuitive ideas about the disturbances which presence of predictable cyclic characteristic due to the compliant legs and passive filters which the camera will be mounted on. In that case, model predictive control can be used as a controller structure. Anyhow, it would be a good challenge to compare the different control strategies according to the performance evaluation by considering the effects of passive filter parameters. After selecting the control strategy, it can be attended to solve the main problem of thesis works; head stabilization. For this purpose, the primary objective is to maintain the state vector of the camera which attached to the head, as close as possible to the origin.

Subject Keywords

Robots, Robots, Intelligent sensors., Robotics.

URI

http://etd.lib.metu.edu.tr/upload/12618282/index.pdf
https://hdl.handle.net/11511/24296

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Single and multi-frame motion deblurring for legged robots: characterization using a novel fd-aroc performance metric and a comprehensive motion-blur dataset Gültekin, Gökhan Koray; Saranlı, Afşar; Department of Electrical and Electronics Engineering (2016) Dexterous legged robots are agile platforms that can move on variable terrain at high speeds. The locomotion of these legged platforms causes oscillations of the robot body which become more severe depending on the surface and locomotion speed. Camera sensors mounted on such platforms experience the same disturbances, hence resulting in motion blur. This is a corruption of the image and results in loss of information which in turn causes degradation or loss of important image features. Most of the studies i...
Optimal control of a half circular compliant legged monopod Özkan Aydın, Yasemin; Leblebicioğlu, Mehmet Kemal; Saranlı, Afşar; Department of Electrical and Electronics Engineering (2013) Legged robots have complex architecture because of their nonlinear dynamics and unpredictable ground contact characteristics. They can be also dynamically stable and exhibit dynamically dexterous behaviors like running, jumping, flipping which require complex plant models that may sometimes be difficult to build. In this thesis, we focused on half circular compliant legged monopod that can be considered as a reduced-order dynamical model for the hexapod robot, called RHex. The main objective of this thesis ...
Intelligent gait control of a multilegged robot used in rescue operations Karalarlı, Emre; Erkmen, Aydan Müşerref; Erkmen, İsmet; Department of Electrical and Electronics Engineering (2003) In this thesis work an intelligent controller based on a gait synthesizer for a hexapod robot used in rescue operations is developed. The gait synthesizer draws decisions from insect-inspired gait patterns to the changing needs of the terrain and that of rescue. It is composed of three modules responsible for selecting a new gait, evaluating the current gait, and modifying the recommended gait according to the internal reinforcements of past time steps. A Fuzzy Logic Controller is implemented in selecting t...
Synchronization of multiple serially actuated robotic legs using virtual damping control Özen, Merve; Saranlı, Uluç; Department of Computer Engineering (2018) Even though one-legged models have been found to be a useful fundamental basis for understanding and controlling the dynamics of running, animals and physical robots alike often use multiple legs for additional support, dexterity, and stability. In general, the dynamics of such multi-legged morphologies are more complex and their control is more difficult. A common problem in this context is to achieve a particular phase relationship between periodic oscillations of different legs, resulting in different lo...
A behavior based robot control system using neuro-fuzzy approach Öğüt, Demet; Alpaslan, Ferda Nur; Department of Computer Engineering (2003) In autonomous navigation of mobile robots the dynamic environment is a source of problems. Because it is not possible to model all the possible conditions, the key point in the robot control is to design a system that is adaptable to different conditions and robust in dynamic environments. This study presents a reactive control system for a Khepera robot with the ability to navigate in a dynamic environment for reaching goal objects. The main motivation of this research is to design a robot control, which i...

Citation Formats

M. O. Öğücü, “Modeling and control of the three degrees-of-freedom parallel manipulated robotic sensor head,” Ph.D. - Doctoral Program, Middle East Technical University, 2014.