Pongsakorn Seekhao - Academia.edu (original) (raw)
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Papers by Pongsakorn Seekhao
Journal of Field Robotics
Mechatronics, 2020
This research focuses on the development of an electric bicycle robot which balances itself while... more This research focuses on the development of an electric bicycle robot which balances itself while moving at a constant forward speed. The bicycle robot is balanced by applying a pendulum mass moving together with heading steering to share the balancing load. The nonlinear dynamics model of a bicycle along with a pendulum is derived from the Euler-Lagrange equation of motion and nonholonomic constraints with respect to translation and rotation relative to the ground plane. This nonlinear model is then linearized around the upright position and combined with the DC motor model to obtain the completed linearized dynamics model. The robot's prototype is designed and built. The linear quadratic regulator (LQR) is implemented on the system to control its balance. The simulation results show that, by varying the control weighting matrix to increase the use of the pendulum's input, the system obtains better performance in both balancing and straight-line path tracking. In addition, the state weighting matrix can be varied to further improve the path tracking performance while still keeping the stability. Real experimental results are also in line with the simulation results.
ABSTRACT Most computer numerical control (CNC) machines used in Thai industry are imported. With ... more ABSTRACT Most computer numerical control (CNC) machines used in Thai industry are imported. With regular maintenance, these CNC machines could last up to 10 years. After that, the owners would either purchase a new machine or upgrade the old model; the later process is widely known as ldquoretrofitting.rdquo However, purchasing a new CNC machine is a big financial burden for small-to-medium enterprises (SMEs) whereas retrofitting usually do not cost much less because most CNC machines are developed based on closed technology. In addition, many models are discontinued after 10 years of service making retrofitting even more costly or nearly impossible. Such problem also permeates educational institutes such as Thai Vocational Technical Colleges, which usually own 5-10 CNC milling and turning machines per institute; that amounts to 400 machines in total that need retrofitting after 10 years of usage. Most of these machines require new industrial motion control cards which had been long discontinued. Hence, an industrial grade CNC motion control prototype system based on open architecture and modular technologies has been developed as a pioneer research project for retrofitting old milling machines for Vocational Technical Colleges.
Journal of Field Robotics
Mechatronics, 2020
This research focuses on the development of an electric bicycle robot which balances itself while... more This research focuses on the development of an electric bicycle robot which balances itself while moving at a constant forward speed. The bicycle robot is balanced by applying a pendulum mass moving together with heading steering to share the balancing load. The nonlinear dynamics model of a bicycle along with a pendulum is derived from the Euler-Lagrange equation of motion and nonholonomic constraints with respect to translation and rotation relative to the ground plane. This nonlinear model is then linearized around the upright position and combined with the DC motor model to obtain the completed linearized dynamics model. The robot's prototype is designed and built. The linear quadratic regulator (LQR) is implemented on the system to control its balance. The simulation results show that, by varying the control weighting matrix to increase the use of the pendulum's input, the system obtains better performance in both balancing and straight-line path tracking. In addition, the state weighting matrix can be varied to further improve the path tracking performance while still keeping the stability. Real experimental results are also in line with the simulation results.
ABSTRACT Most computer numerical control (CNC) machines used in Thai industry are imported. With ... more ABSTRACT Most computer numerical control (CNC) machines used in Thai industry are imported. With regular maintenance, these CNC machines could last up to 10 years. After that, the owners would either purchase a new machine or upgrade the old model; the later process is widely known as ldquoretrofitting.rdquo However, purchasing a new CNC machine is a big financial burden for small-to-medium enterprises (SMEs) whereas retrofitting usually do not cost much less because most CNC machines are developed based on closed technology. In addition, many models are discontinued after 10 years of service making retrofitting even more costly or nearly impossible. Such problem also permeates educational institutes such as Thai Vocational Technical Colleges, which usually own 5-10 CNC milling and turning machines per institute; that amounts to 400 machines in total that need retrofitting after 10 years of usage. Most of these machines require new industrial motion control cards which had been long discontinued. Hence, an industrial grade CNC motion control prototype system based on open architecture and modular technologies has been developed as a pioneer research project for retrofitting old milling machines for Vocational Technical Colleges.