# Enhancing Street-Crossing Safety for Visually Impaired Pedestrians with Haptic and Visual Feedback
## 1 Introduction  
Approximately 220 million people worldwide live with visual impairments [1], facing numerous challenges in daily life, with mobility safety being particularly critical [2, 3]. For the general population, crossing the street is a simple task, but for individuals with visual impairments, it is fraught with risks and uncertainties [4, 5]. Research shows that safe street-crossing decisions primarily depend on two key factors [6]: the time required for a pedestrian to cross the road and the available time before the next vehicle arrives. However, empirical evidence reveals concerning real-world conditions: drivers yield to pedestrians with white canes at a rate of only 37% [7], forcing visually impaired individuals to exercise extra caution in evaluating crossing opportunities. Moreover, the complexity of many intersections and the interference of street noise [8] further exacerbate the difficulties and safety risks faced by visually impaired pedestrians. Therefore, developing effective street-crossing assistive systems is of critical and urgent importance to improve the mobility safety of individuals with visual impairments. With advancements in the Internet of Things (IoT) and vehicle-to-everything (V2X) technologies, smart infrastructure can now collect and communicate real-time traffic information, such as traffic light status and approaching vehicles. Wearable and handheld assistive devices for visually impaired pedestrians can leverage these data to provide timely feedback that enhances their awareness of crossing conditions. Existing assistive technologies, such as smartphone navigation [9; 10; 11; 12], smart canes [13; 14; 15], and intelligent guide robots [16; 17; 18] have made significant progress in daily navigation. These technologies, developed through both laboratory research and field studies, have demonstrated considerable success in general mobility assistance and route guidance. However, these technologies still face challenges in conveying information effectively in street-crossing scenarios, particularly in communicating critical information such as the remaining time for pedestrian traffic lights [5; 19; 20] and safe crossing gaps [21]. Traditional auditory feedback faces notable limitations in street environments: environmental noise can mask critical auditory cues [22], and it may lead to auditory channel overload, impairing the ability of visually impaired individuals to perceive surrounding environmental sounds [23]. As promising alternatives, haptic and visual feedback provide visually impaired individuals with a clear and distinguishable means of receiving cues, even in noisy environments. The existing research has shown that haptic feedback can effectively avoid interference from environmental noise, enabling users to perceive vibration signals quickly and accurately [24; 25; 26]. At the same time, 90% of visually impaired individuals retain some degree of light perception [2; 3; 27], allowing them to detect the position, motion, and brightness changes of light sources [28]. This opens up significant opportunities for the development of visual cue systems based on residual light perception [27]. The widespread presence of this residual light perception capability represents an underutilized channel for assistive technology development, particularly in navigational contexts requiring rapid decision-making. Despite these known advantages of both feedback modalities, a significant research gap exists in understanding their comparative effectiveness across different street-crossing contexts. While individual studies have explored haptic systems [29; 30] and light-based cues [27] separately, few have systematically compared their performance or investigated how varying parameters within each modality affect decision-making. Research has shown different effectiveness patterns depending on the task and environment [27], highlighting the need for context-specific evaluations.