## 2 Related Work
### The Definition of Trust in Human-Robot Interaction  
The concept of trust varies in its definition and interpretation across diverse academic fields. In social sciences, trust is seen as essential for social interaction, incorporating both emotional and cognitive facets [28]. From a psychological perspective, trust is framed as a risk management tool, preparing for potential harm that might arise from others' actions. In the realm of economics, trust is perceived as an outcome of a robust economic system, which in turn enhances the system's efficiency [29]. Despite the varied definitions across disciplines, there's a shared emphasis on the importance of trust in bilateral transactions or exchange relationships [30]. Interpersonal trust, as a key component in human relationships, establishes the foundation for these interactions. [PERSON] et al. suggest that the evolution of interpersonal trust is a dynamic process, transitioning from trust based on rational choices and economic exchanges to trust rooted in interpersonal reliance and identification [31]. The existence of interpersonal trust assists individuals in making appropriate decisions and taking action when confronted with uncertainties. In the context of HRI, trust in robots also implies an acknowledgment of potential unknown risks. Trust is thus defined as \"one party's willingness to accept risks or potential harms from another\" [32]. For example, [PERSON] et al. define human trust in AI as the degree to which humans rely on intelligent agents [33]. Simultaneously, other researchers have also emphasized the significance of the robot's reliability, integrity, and capabilities in shaping trust [34]. Building upon previous studies, this paper offers the following definition of trust in HRI: as illustrated in Figure 1, in HRI, trust represents the human's intention to rely on the robot. It measures how much the human (Trustor, the one placing trust) believes in the actions and reliability of the Robot (Trustee, the entity being trusted). The notion of \"trust\" should extend beyond mere task success rates or cognitive levels at specific points in time. Instead, it should delve into the nuances of the collaborative process between the involved parties [35]. This perspective is crucial because trust, whether in interpersonal dynamics or HRI, is continually formed and evolves throughout the interaction [36]. Research within sociology breaks down the evolution of trust into two distinct phases:  
1. Static Trust: Often referred to as initial trust in many studies, static trust is established before any interactive relationship has begun. At this stage, due to a limited understanding and incomplete information about the Trustee, the Trustor faces potential risks. These risks can arise from the Trustee failing to meet expectations, either intentionally or unintentionally. Consequently, when establishing static trust, the Trustor typically relies on cognitive judgment to make decisions about the present situation [37]. 2. Dynamic Trust: Dynamic trust emerges after the establishment of the interactive relationship and stems from the Trustor's enhanced understanding of the Trustee. Such an understanding sometimes allows the Trustor to anticipate the Trustee's actions. The core of dynamic trust involves factoring the results of prior interactive actions into future trust decisions. The outcomes, whether positive or negative, will manifest in the subsequent interaction between the Trustor and the Trustee, thereby further influencing trust [38]. [PERSON] suggests that trust in HRI is also an evolving process [39]. As individuals become more acquainted with artificial intelligence, their trust in robots tends to increase, fostering a more optimistic perspective. In the context of HRI, trust fluctuates based on the alignment of human expectations with the robot's demonstrated capabilities. This progression is cultivated through continuous bidirectional interactions between humans and robots. Many studies have investigated this interaction process from various angles.