Hardware, no funding, prototype
Your first step is to bootstrap funding to obtain a rough prototype. Then you can seek out additional funding to develop additional iterations of a prototype.
If a development expert doesn't weigh in here, contact the countless success stories on Kickstarter to find out what they have learned during their startup process.
Your first step should be finding someone with experience in hardware and getting their insight into the feasibility of your product. That person will need to give you a sense for how unique your product is compared to what already exists, if it can be made with current manufacturing processes or needs something custom, and how much it would cost you to develop a prototype and a final version ready for market. You may find that you can use existing processes or technology to create something simple on the cheap. Or, it might be really complicated and expensive, which means you may want to look elsewhere for product ideas since the path to market with hardware is typically quite a bit more expensive than with services or software. You really want to know what you are getting yourself into with your specific product before you spend money on developing a prototype.
I'd also suggest researching similar products (or products that have a foundation in similar hardware technology but are in different form) to see how much you can reverse engineer when thinking through how your product will be made. Look at their costs, price points, and demand, and see how they compare to what you want to build.
Best of luck!
The hardware development arena is super competitive and the big boys hold a lot of leverage in this space with resources, patents, and enough engineering team members to fill stadiums. Computer hardware isn't really where the secret sauce is anymore, it's in the software. That said, without knowing the details of what you have, I'd take the following steps:
1. Search for any patents related to your idea: https://www.google.com/?tbm=pts&gws_rd=ssl
2. Find comparable products in the market and see if you can find reference to the type of hardware you have on anyone's roadmaps.
3. Search high and low in forums, online tech magazines, etc. to see if you can find any similar references.
If all of these come back favourably, your next step would be to engage with a partner and see if it is valuable. My strategy for this wouldn't be reaching out to the top dogs, I'd find some influential people on twitter to start engaging with.
To get too detailed on the strategy I'd want to spend some time with you asking questions about the hardware, applications, specifications, etc. If you'd like to talk in more detail feel free to schedule some time with me.
Good luck either way!