How do you validate a B2B startup idea when your potential customers are researchers who are hard to reach?

I’m currently in the early idea validation stage of a startup, and I’m struggling to figure out what my next step should be.

The idea is to build a platform that collects real-world audio and video data through contributors using wearable devices (such as smart glasses). The goal is to provide useful datasets for robotics, embodied AI, and multimodal AI researchers.

I already have a basic platform and 150+ registered contributors, but I haven’t validated whether researchers actually need this type of data or would be willing to pay for it.

Here’s where I’m stuck:

• Cold outreach: I’ve emailed professors and researchers whose papers are relevant to the idea, but haven’t received any responses so far.
• Conferences: I looked into robotics and AI conferences to meet researchers in person, but many cost $1,000+, which feels like a lot to spend before validating the idea.
• Customer discovery: I want to talk to people who actually work with these datasets, but I’m having trouble finding a way to reach them.

I’m trying to avoid the mistake of building something nobody needs, so I’d rather validate the problem before investing more time and money into the platform.

For those who’ve built B2B startups targeting researchers, technical teams, or other hard-to-reach customers:

1. How did you get your first conversations with potential customers when cold emails weren’t working?
2. Are expensive conferences worth attending at this stage, or are there better alternatives?
3. Would you recommend creating a small sample dataset or prototype first, even before confirming demand?
4. What would you prioritize if you were in my position?

I’m not looking to promote anything. I’m genuinely trying to figure out how to validate demand without spending thousands of dollars or months building the wrong thing.

I’d really appreciate hearing what worked for you, what didn’t, and what you wish you’d done differently.