Journal of Food, Agriculture and Environment




Vol 9, Issue 2,2011
Online ISSN: 1459-0263
Print ISSN: 1459-0255


Electro-hydraulic control system for precision guidance of a row crop cultivator with position feedback via LVDT


Author(s):

Javad Robati 1, Hossein Navid 2, Iraj Hasanzadeh 3, Mahdi Rezaei 4

Recieved Date: 2010-12-10, Accepted Date: 2011-03-27

Abstract:

Precision guidance of agricultural implements is one of the goals that followed by precision agriculture systems. Despite of using low volume spraying techniques, mechanical control of weed using row crop hoes is still utilized by a significant number of farmers. In this paper, an electro-hydraulic control system was designed to control the lateral movements of a row crop cultivator in the presence of the tractor directional motion and the measurement noise. A sinusoid path assumed for the tractor by amplitude of 15 cm and period of 50 m with a constant forward speed of 2 m s-1. It is also assumed that the instantaneous coordinates of the tractor and implement are obtained from a DGPS receiver with standard deviation of 8.594e-3 m and 1.104e-2 m at the X and Y directions, respectively. Hydraulic actuator consists of a servo valve and servo cylinder. The design has been performed for MOOG series 72 servo valves with the nominal flow rate of 96.75 l min-1. The hydraulic cylinder was adopted from Shore- Western manufacture products 91series. The actuator dynamics was modeled by a five order system consisting of a two order transfer function for the servo valve and a three order transfer function for the servo cylinder. Different parameters of the servo valve and servo cylinder adopted from the commercial series. At first, an internal controller was designed for the precision control of the actuator and then, the actuator was used to control the lateral motions of the implement. The standard deviation of the implement lateral position was 4.6e-3 m when the PI-controller had settled. The validity of the proposed control system was verified by computer simulation.

Keywords:

Row-crop hoe,  simulation, PI-controller, row-crop, cultivator, electro-hydraulic, DGPS, root locus, actuator, servo valve


Journal: Journal of Food, Agriculture and Environment
Year: 2011
Volume: 9
Issue: 2
Category: Environment
Pages: 556-560


Full text for Subscribers
Information:

Note to users

The requested document is freely available only to subscribers/registered users with an online subscription to the Journal of Food, Agriculture & Environment. If you have set up a personal subscription to this title please enter your user name and password. All abstracts are available for free.

Article purchasing

If you like to purchase this specific document such as article, review or this journal issue, contact us. Specify the title of the article or review, issue, number, volume and date of the publication. Software and compilation, Science & Technology, all rights reserved. Your use of this website details or service is governed by terms of use. Authors are invited to check from time to time news or information.


Purchase this Article:   20 Purchase PDF Order Reprints for 15

Share this article :