400 Commonwealth Drive, Warrendale, PA 15096-0001 U.S.A. Tel: (724) 776-4841 Fax: (724) 776-0790 Web: www.sae.org SAE TECHNICAL PAPER SERIES 2007-01-4248 Model-Based Design for Off-Highway Machine Systems Development Sameer M. Prabhu The MathWorks, Inc. Commercial Vehicle Engineering Congress and Exhibition Rosemont, Illinois October 30-November 1, 2007 Downloaded from SAE International by Univ of California Berkeley, Monday, July 30, 2018The Engineering Meetings Board has approved this paper for publication. It has successfully completed SAE's peer review process under th e supervision of the session organi zer. This process requires a minimum of three (3) reviews by industry experts. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. For permission and licensing requests contact: SAE Permissions 400 Commonwealth DriveWarrendale, PA 15096-0001-USAEmail: [email protected]: 724-772-4028 Fax: 724-776-3036 For multiple print copies contact: SAE Customer Service Tel: 877-606-7323 (inside USA and Canada)Tel: 724-776-4970 (outside USA)Fax: 724-776-0790Email: [email protected] ISSN 0148-7191 Copyright © 2007 The MathWorks, Inc. Positions and opinions advanced in this paper are those of the author(s ) and not necessarily those of SAE. The author is solely responsible for the content of th e paper. A process is available by which discussions will be printed with the pap er if it is publishe d in SAE Transactions. Persons wishing to submit papers to be considered for presentation or publicat ion by SAE should send the manuscript or a 300 word abstract to Secretary, Engineering Meetings Board, SAE. Printed in USADownloaded from SAE International by Univ of California Berkeley, Monday, July 30, 2018ABSTRACT The increased adoption of electronic controls in off- highway machines increases the complexity of typical machine systems and stresses the traditional process used to develop these machines. To address this issue design engineers are turning from the traditional design methods to Model-Based Design. By using models in the early design stages, engineers can create executable specifications that enable them to immediately validate and verify specifications against the requirements. These models also allow the machine designer to evaluate the complex interactions between mechanics, hydraulics, electronics and other physical phenomena and thereby detect design errors earlier when the cost to fix them is less. This paper presents a model-based approach for developing off-highway equipment machine systems. A dynamic model of the machine and the electro-hydraulic implement and propulsion system is developed and used to verify the overall machine behavior. The models are linked to the machine requirements and instrumented to check the simulation results to achieve verification of machine behavior against requirements in a formal way. 1. INTRODUCTION MACHINE SYSTEMS DEVELOPMENT CHALLENGE Electronic controls in off-highway equipment are growing rapidly as a result of regulatory requirements such as emissions restrictions and customer demands for increased machine productivity, uptime, and safety. The design of a typical off-highway machine is already a difficult challenge due to the complex interaction of various individual systems and it is complicated further by introducing electronics and the accompanying system behavior adaptability. To better understand why this is the case, let us consider the example of a wheel loader. One of the most common applications for a wheel loader is what is referred to as hopper charging wherein the loader acquires material from a stockpile, backs up from the stockpile, reverses direction, traverses the distance towards a ramp, and then moves up the ramp while raising the implement