Ming-Shyan Wang, Seng-Chi Chen, Wei-Chin Fang and Po-Hsiang Chuang
Extensive efforts have been conducted on the improvement of torque ripple in switched reluctance motor (SRM) drive. The purpose of this paper is to estimate initial on time of…
Abstract
Purpose
Extensive efforts have been conducted on the improvement of torque ripple in switched reluctance motor (SRM) drive. The purpose of this paper is to estimate initial on time of pulse-width modulation (PWM) and turn-off angle using the motor speed and rotor angle by fuzzy logic.
Design/methodology/approach
A fuzzy logic control together with the PWM technique and turn-off angle are used to improve torque ripple and dynamic response.
Findings
After determining initial on time of PWM, the rise slope of phase current is increased.
Research limitations/implications
Future work will consider to increase the complex of the fuzzy control to adaptively tune parameters and achieve excellent results.
Practical implications
The experimental results of the proposed method are presented to show the effectiveness.
Originality/value
This paper achieves SRM control by one special PWM technique which is seldom studied.
Details
Keywords
Jenq-Ruey Horng, Ming-Shyan Wang, Tai-Rung Lai and Sergiu Berinde
Extensive efforts have been conducted on the elimination of position sensors in servomotor control. The purpose of this paper is to aim at estimating the servomotor speed without…
Abstract
Purpose
Extensive efforts have been conducted on the elimination of position sensors in servomotor control. The purpose of this paper is to aim at estimating the servomotor speed without using position sensors and the knowledge of its parameters by artificial neural networks (ANNs).
Design/methodology/approach
A neural speed observer based on the Elman neural network (NN) structure takes only motor voltages and currents as inputs.
Findings
After offline NNs training, the observer is incorporated into a DSP-based drive and sensorless control is achieved.
Research limitations/implications
Future work will consider to reduce the computation time for NNs training and to adaptively tune parameters on line.
Practical implications
The experimental results of the proposed method are presented to show the effectiveness.
Originality/value
This paper achieves sensorless servomotor control by ANNs which are seldom studied.
Details
Keywords
Nino Pereira, Fernando Ribeiro, Gil Lopes, Daniel Whitney and Jorge Lino
The purpose of this paper is to present the methodology and the results on the design and development of an autonomous, golf ball picking robot, for driving ranges.
Abstract
Purpose
The purpose of this paper is to present the methodology and the results on the design and development of an autonomous, golf ball picking robot, for driving ranges.
Design/methodology/approach
The strategy followed to develop a commercial product is presented, based on prior identification requirements, which consist of picking up golf balls on a driving range in a safe and efficient way.
Findings
A fully working prototype robot has been developed. It uses two driving wheels and a third cast wheel, and pushes a standard gang which collects the balls from the ground. A hybrid information system was implemented in order to provide a statistically relevant prediction of golf balls location, to optimize the path the robot has to follow in order to reduce time and cost. Autonomous navigation was developed and tested on a simulation environment.
Research limitations/implications
Preliminary results showed that the new path planning algorithm Twin‐RRT* is able to form closed loop trajectories and improve the result over time. Kinematic constraints were already taken into account on the algorithm. This sampling based algorithm has potential usage in solving other TPP (Travelling Purchaser Problem) related problems.
Practical implications
The prototype feasibility is being tested in real driving ranges. It has autonomy of up to 8 h per day. It is capable of collecting up to 1,200 balls in one single journey. It weighs 130 kg and is capable of climbing slopes of up to 22°. The maximum speed is 8 km/h and the robot takes 140 min to completely sweep a 25,000 m2 field at 7.2 km/h (2 m/s) average speed.
Social implications
There are about 30,000 golf practice fields, of which 18,000 are located in the USA and Canada. In some countries the golf industry represents more than 15 per cent of tourism GNP. In a typical practice field, about 10,000 balls have to be picked up every day.
Originality/value
An important contribution of this paper is the algorithm for path planning in order to optimize the ball pick up task, reducing time and cost. There are two patents are pending concerning the technological novelties of this work.