DARVA – The Event Assistant: From Felt to Live Animation

DARVA is a charming animated robot created to enrich event experiences by engaging attendees in natural conversations, cutting down on repetitive explanations.

Overview

• Introduction and Showcase Video
• Analog Robot Construction
• Digitizing the Design
• Virtual Assistant Development
• Deploying on Raspberry Pi 4
• Final Presentation of DARVA

Introduction and Showcase Video

DARVA’s name stands for Digitized Analog Robot Virtual Assistant. The following video demonstrates how DARVA interacts with guests and reduces repetitive tasks for event staff.

Analog Robot Construction

The journey begins with a handcrafted analog model. After sketching a prototype, I cut the components from felt, ensuring each part is individually separable for later animation. Sewing each edge gives DARVA a tactile, handmade look. Double‑layered felt sections add durability while keeping the overall weight low.

Tip: Photograph the complete set before cutting; these images can serve as a consistent background for digital slicing.

Digitizing the Design

Once the analog model is complete, spread the parts on a contrasting background to simplify segmentation. Capture a single high‑resolution image to preserve scale. Use photo‑editing software to isolate each component, saving them as PNG files with transparent backgrounds. Photoshop’s Quick‑Selection tool was particularly effective, requiring only minor manual refinement.

With the digital assets ready, the robot can now be animated.

Virtual Assistant Development

To bring DARVA to life on any platform, I built a lightweight web page utilizing the HTML canvas element and vanilla JavaScript. For smooth, cross‑browser animation, I incorporated Create.js and Tween.js. All libraries are bundled locally, ensuring full offline functionality—a critical feature for events with unreliable internet.

The script handles:

• Loading PNG assets
• Scaling, rotating, and positioning them on the canvas
• Animating movements and expressions
• Dynamic speech bubbles that change every five seconds
• Interactive triggers on the head and belly

Randomized eye movements and gauge rotations add a touch of realism, while calculated animations keep the presentation polished.

Deploying on Raspberry Pi 4

To run DARVA in a portable, low‑power setup, I deployed the web page on a Raspberry Pi 4 connected to a portrait‑mode touchscreen. Although the Pi’s display rotation can be set to landscape, the touch panel maintained a reverse orientation, so I opted to keep the Pi in landscape mode and rotate the canvas animations instead. This approach simplified layout adjustments and preserved the animation timeline.

Initial testing in Chromium exhibited occasional rendering hiccups; subsequent revisions resolved these glitches. Firefox also runs the animations smoothly, albeit with slightly lower frame rates. Offline mode remains fully functional across both browsers.

DARVA in Action

With all components integrated, DARVA is ready to greet guests, answer common questions, and streamline event operations. The project showcases how a simple felt model can evolve into a sophisticated, self‑contained digital assistant.

Source: DARVA – The Event Assistant