PSI - Issue 14

Abhijit Kulkarni et al. / Procedia Structural Integrity 14 (2019) 158–167 2 Abhijit Kulkarni a , Rushikesh Nanaware b , Akhilesh Kulkarni c , Vikrant Garud d / Structural Integrity Procedia 00 (2018) 000–000

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Nomenclature w Width b Wheel base � Inner angle of tractor; � Outer angle of tractor r Radius of rotation of tractor Articulation angle R Radius of rotation of trailer CG � t 1 Distance between CG and first axle t 2 Distance between CG and second axle ∅ �� Inner angle of first axle ∅ �� Outer angle of first axle ∅ �� Inner angle of second axle ∅ �� Outer angle of second axle 1. Introduction

Distance between fifth wheel center and CG

A semi-trailer is a trailer without a front axle. A large proportion of its weight is supported either by a road tractor or by a detachable front axle assembly known as a dolly. A semi-trailer is normally equipped with legs, called "landing gear", which can be lowered to support it when it is uncoupled. As per AIS-053[4], a semi-trailer means a trailer, which is intended to be connected to a motor vehicle and which is so constructed such that a portion of it is superimposed on and a part of whose weight is borne by the haulage tractor. Articulated vehicles have proven their economic profitability, but as the number of these vehicles grows, it is observed that there is a need to improve their performance in terms of handling and control. Benefits of such steerable trailers includes reduced turning space, increased load capacity, reduced fuel consumption, reduced road surface damage which helps to improve the low speed maneuverability of the vehicle as well in reducing tire scrub while negotiating sharp corners and small roundabouts.

Fig. 1. Fixed Axle Turning Center.

For the Steerable Trailer under consideration, it was observed that there were high steering errors throughout the range of operation and that the tie rod mechanism’s pin bends/sheared off at higher articulation angles. In order to find the root cause of the problem reported, it was decided to study the behavior of the existing steering system and the inbuilt limitations of the mechanical parts throughout the working range. The objective of this work is to reduce the errors in angle turned by the wheels and to avoid shearing of tie rod pin joint during turning. While achieving