## 2 Materials and Methods
### Key Features of the Haptic Feedback Design Tool
This enables tool users to create highly specific haptic effects that may not be achievable with curve presets alone, giving them greater control over the nuances of the feedback. Curves generated with this tool can be copied and pasted directly into any curve field within the Unity Editor, providing seamless integration. The Animation Curve Generator tool was intentionally developed as a separate editor window, because animation curves have a wide range of use cases, such as controlling character animations, object and camera movement patterns, or even sound modulation. As such, it can function as a standalone tool, providing versatility for custom curves in various applications and improving the general engine workflow. The AI Haptic Advisor provides AI-generated recommendations for designing haptic effects based on the specified use case and additional descriptions (Figure 4b). It also supports the automatic creation of new haptic effect files based on these recommendations, as well as the evaluation and automatic modification of existing effects. After a new effect is generated or an existing one is modified, the Project window automatically navigates to the location where the effect is saved, highlights it visually, and displays it in the Inspector for immediate preview and eventual further adjustments. The recommendations provided by the AI Haptic Advisor tool are comprehensive and include formal design justifications  
Figure 3: (**a**) Creating a Haptic Effect using Animation Curve Editor with timeline, grid lines, and curve presets. (**b**) Editing tools for animation curve keys. (**c**) Built-in, user-defined curve presets and preset options. (**d**) Clipboard functionality for copying and pasting curves. to help tool users understand the alignment between the proposed haptic feedback effect and its intended use case. This clarifies the reasoning behind the recommendation and offers educational value, guiding users in grasping the principles of effective haptic design and its application in various contexts. Technically, the AI Haptic Advisor is implemented as a Unity-integrated interface that communicates with external AI models via API calls. The prompts are specifically tailored for the haptic design use case and are dynamically generated to include contextual information, recent project data (e.g., effect types, user preferences), and relevant design guidelines. The returned output is parsed, validated, and structured into Unity-compatible haptic effect assets. All AI-generated content is additionally post-processed to ensure compatibility with the haptic engine and prevent unsupported configurations. The AI Haptic Advisor tool has demonstrated its functionality and effectiveness in its development version by utilizing the APIs of existing AI models, particularly ChatGPT (version GPT-3.5) and, more recently, DeepSeek (version R1). Both the Animation Curve Generator and the AI Haptic Advisor tools are freely movable and dockable within the Unity Editor workspace, as shown in Figure 1 (top right corner), where they are docked as tabs next to the Inspector tab. This design enhances usability by allowing tool users to customize their workspace layout to suit their preferences. Alternatively, these tools can be accessed via the Tools option in the menu bar of the Unity Editor. Expanding the possibilities for haptic effect creation and empowering synchronization with other feedback systems, the tool enables users to create haptic effects from audio files, with animation curves automatically generated to match the audio clip's waveform. Audio clips are converted into haptic effects by transforming the audio signals from the left and  
Figure 4: Additional tools integrated within the haptic feedback design tool: (**a**) Animation Curve Generator tool enables users to create and fine-tune custom animation curves for haptic effects. (**b**) AI Haptic Advisor tool utilizes artificial intelligence to recommend optimal haptic feedback settings based on specific use cases.