The technology for terrain detection and walking support system for blind people has
rapidly been improved the last couple of decades but to assist visually impaired people may have
started long ago. Currently, a variety of portable or wearable navigation system is available in the
market to help the blind for navigating their way in his local or remote area. The focused
category in this work can be subgroups as electronic travel aids (ETAs), electronic orientation
aids (EOAs) and position locator devices (PLDs). However, we will focus mainly on electronic
travel aids (ETAs). This paper presents a comparative survey among the various portable or
wearable walking support systems as well as informative description (a subcategory of ETAs or
early stages of ETAs) with its working principal advantages and disadvantages so that the
researchers can easily get the current stage of assisting blind technology along with the
requirement for optimising the design of walking support system for its users
