## 2 Related Work
### Factors Influencing Trust in Human-Robot Interaction  
In HRI, the factors shaping trust are both vast and complex. They span human emotions, personality, cognitive abilities, robot performance, algorithm quality, and precision, as well as external conditions like temperature, humidity, application scope, and task complexity. Essentially, trust levels in HRI are determined by a blend of human attributes (from the Trustor), robot characteristics (from the Trustee), as well as a myriad of external environmental factors. A significant body of research is directed at bolstering robot reliability through technological enhancements, aiming to consequently increase human trust in robots. The capability of a robot greatly dictates the success of predefined tasks. Therefore, refining robot performance to align with human anticipations becomes a critical strategy for fortifying human trust in HRI [44]. [PERSON] et al. emphasized that the cornerstones for establishing this trust encompass robot reliability, robustness, effectiveness, transparency, and clarity of intent [37]. Similarly, [PERSON] et al. evaluated shifts in trust centered on robots, viewing it through three lenses: the trustworthiness of AI, the inherent assurances  
Figure 1: Schematic diagram of the evolution of trust in HRI. offered by robots, and an ethical framework for trustworthy robots [45]. They assert that accentuating these three facets can elevate a machine's credibility and societal endorsement, thereby enriching trust in HRI. Trust in HRI is not solely determined by the robot's qualities; human subjective factors also play a significant role. Personal preferences and mental resilience play a significant role in forming trust with robots; because people have distinct cognitive abilities, personalities, and emotional reactions, each person encounters specific challenges when trying to trust robots [46]. [PERSON] et al. found that, regardless of the cognitive level, as individuals become more familiar with artificial intelligence, the degree of trust in robots correspondingly increases [47]. Furthermore, [PERSON] et al. explored how personality traits such as extroversion, introversion, and conscientiousness impact human trust. Their findings revealed that these traits have varied influences on trust, particularly under conditions of uncertainty and high cognitive demands [48]. In addition to human and robot factors, the environment significantly shapes trust in HRI. Factors such as geographical location, cultural background, task hazards, and task difficulty can all influence trust either positively or negatively. Notably, during HRI, the variance in task difficulty can cause shifts in the dependency on AI, thereby influencing the level of trust. Sociological findings have shown that task difficulty can sway individual self-perception [49], and psychological studies demonstrate its impact on emotional responses and heart rates [50]. Within the HRI, [PERSON] et al. examined trust during visual search tasks of varying difficulty. Their results indicated that trust in robots increased as tasks grew more complex [11]. However, current studies addressing the influence of environmental factors on human trust in robots remain in their infancy. There is a gap in understanding whether task difficulty impacts trust in a static or dynamic manner. Moreover, few empirical investigations exist on the subject. Against this backdrop, our study focuses on understanding how task difficulty, considered as an environmental factor, influences trust in HRI. Drawing from methodologies in psychological and sociological trust research, and building upon the latest insights in HRI, we approach this topic from an environmental perspective. Our objective is to explore the effects of varying task difficulties on dynamic trust during HRI. Based on this, we propose the following hypotheses:  
**H1. **: _Different task difficulties during HRI significantly influence dynamic trust between humans and robots._
**H2.