Browsing by Author "Abeysiriwardhana, WASP"

Now showing 1 - 6 of 6

item: Thesis-Full-text
Active vibration suppression with disturbance force estimation
Abeysiriwardhana, WASP; Abeykoon, AMHS
Vibration is a basic phenomenon that has attached control engineering’s attention for many decades. Vibration rejection in control systems is implemented with passive, semi active and active vibration suppression systems. These methods commonly use multiple redundant sensors. Multiple sensor usage and complex control has implemented the cost of operation and complexity. Minimal sensor usage to provide vibration suppression within the commonly used acceleration or deflection observation could be used to reduce the complexity and the cost of the system. This dissertation proposes a novel methods which uses either the acceleration or motor deflection measurement based disturbance force observe for vibration observations and to suppress the vibrations with active vibration suppression. The proposed system is capable of estimating the disturbances and compensate disturbance using the only a acceleration or suppression deflection sensory data. Proposed system still could work as a traditional vibration suppression system in case of a failure to active system. Active for to be injected is calculated based on the disturbance forces acting on the sprung mass. A novel method is proposed for spring and damper parameter measurements with electromagnetic actuators which enhance the overall system performance. A Quarter car model is used to illustrate the adaptability, robustness, and the vibration suppression capabilities of the system. Performance of the active vibration suppressor and disturbance observer is measured using system simulations and practical results. Simulation and practical system responses provide evidence of robust vibration suppression capabilities of the proposed method under different conditions.
item: Conference-Full-text
Field based navigation for 3d obstacle avoidance
(IEEE, 2016-04) Wickramaratna, SD; Udage, AS; Jayasekara, RT; Kariyapperuma, DA; Abeysiriwardhana, WASP; Abeykoon, AMHS; Jayasekara, AGBP; Bandara, HMND; Amarasinghe, YWR
Mobile Robot Navigation techniques are important for path calculation towards a target, avoiding collisions in an unknown environment. The existing robot navigation techniques conclude a diverse spectrum of applications in 2D space. But navigation solutions in 3D space have been hardly addressed by the researchers for a combination of a mobile platform and a robot arm. This paper proposes a novel technique for navigation planning in 3D space for a combination of a mobile platform and a robot arm. The proposed method was derived using the field based navigation techniques to the robot end effector. Applicability of the proposed mathematical model was first derived and simulated for a 2D environment. Proposed mathematical model applicability in 3D space for a single obstacle environment and multiple obstacle environment was analyzed in this paper. The 3D model can be applied to a robot with end effector and the complete solution set was given to overcome the drawbacks of the system. The performance and applicability of the proposed navigation model is also confirmed using a Matlab simulation. The tuning of the model would create different path trajectories and these would be applicable for different types of environments. The proposed algorithm can be applied in a mobile robot platform with a robot arm and sensors to detect depth and position of robot.
item: Conference-Abstract
Simulation of active vibration suppression using internal motor sensing
Abeysiriwardhana, WASP; Abeykoon, AMHS
Suppression of unnecessary vibration is an important aspect in control system design. Passive, semi active, and active suspension systems are used in vehicles to suppress vibrations and theoretically active suspension systems provide superior performance than the prior two types. This paper proposes a novel method to suppress vibrations using internal motor sensing method. The proposed active vibration suppression system uses a reaction force observer to measure and suppress vibrations acting on the system without using environmental sensors. The motor forcer acceleration and a current sensor measurements are used by the reaction force observer to measure the vibration forces in the system. The proposed system performed system performance, robustness, and applicability is evaluated using quarter car suspension system model. The proposed system is simulated for different conditions to measure the system vibration suppression capabilities. The simulation results provide evidence of robust vibration suppression capabilities and applicability of the controller for real world applications.
item: Conference-Abstract
Simulation of brake by wire system with dynamic force control
Abeysiriwardhana, WASP; Abeykoon, AMHS
By wire technology is recently developed to improve the reliability, safety, and performance of vehicular drive technology. Brake system is the most important control system for vehicle safety. By wire technology development has encouraged the development of brake by wire systems to reduce traditional mechanical and hydraulic systems usage in automobiles. This paper proposes a novel brake by wire controller that uses a reaction force based bilateral motor controlling method. The proposed system uses two linear actuators with disturbance observer and reaction force observers to provide pedal force amplification and pedal retraction capabilities. The system includes a force controller to provide pedal feel to drivers. Electro mechanical brake position control is used to provide the brake force. The proposed system is simulated for different conditions to measure the performance and robustness. The simulation results provide evidence for robustness, force amplification, and pedal and brake retraction capabilities of the system.
item: Conference-Abstract
Simulation on active vibration suppression using virtual spring-damper combination
(2014-06-19) Abeyrathna, PAMMB; Abeysiriwardhana, WASP; Amarasinghe, SW; Ariyasinghe, WMSL; Abeykoon, AMHS
Active suspension is an emerging technology used to improve the contact, comfort and control of vehicles and in other vibration suppression applications. Different methods are used to control the actuator force exerted between the sprung mass and unsprung mass in order to achieve the active suspension. Most of the other research areas have introduced LQR controllers, Fuzzy logic controller methodologies. But this paper presents a control method based on a virtual spring-damper combination. A linear motor model is expected to be used as the actuator in realizing the values of the virtual spring damper. The simulation results show the sprung mass displacement with and without the active suspension when subjected to a large disturbance. The success and the limitations of the proposed virtual spring-damper combination are discussed with the simulation results.
item: Conference-Full-text
Vibro-haptic white cane with enhanced vibro sensitivity
(Institute of Electrical and Electronics Engineers, Inc., 2018-09) Abeysiriwardhana, WASP; Ruwanthika, RMM; Abeykoon, AMHS; Samarasinghe, R; Abeygunawardana, S
The traditional white cane allows blind persons to understand the environment by tapping the white cane against the objects. It has limited capabilities in detecting objects far from the person. Available electronic blind navigation systems require wearable devices that would cause discomfort to the blind person. This paper proposes a low cost but yet a rugged vibro-haptic white cane to be used as a navigational aid for the blind community. The proposed system allows a blind person to understand distant environment with haptic sensations without any additional wearable devices. The frequency of vibration utilized as the sensation of distance. Proposed device was tested with blind middle school students. The proposed controller was modified accordingly to create a linear distance perception.