Larry Niven had zero g sleeping plates in his Known Space series.  Of
course he listed virtues of zero G beds that didn't include sleeping.

On 5/19/2022 11:03 AM, Jim Vassilakos - jim.vassilakos at gmail.com (via
tml list) wrote:
> In a future where artificial gravity is fairly commonplace, might
> people be able to change the gravity setting of their bed in order to
> create a softer sleep, say by reducing one's weight by 20-50%?
>
> Would there be health risks in doing so?
>
> Actually, I came up with this idea decades ago. Back then, I called
> them null tubes. My thought was that people might choose to sleep in
> zero gravity. But since then, I came across reports of health problems
> faced by astronauts due to prolonged exposure to zero gravity.
> However, I'm not 100% sure that being at zero gravity only while
> sleeping would necessarily constitute a health risk. I'm curious to
> know what the list thinks.
>
> And if you think it's safe, would you use such a bed, and at what
> percentage would you set its gravity?
>