4 ms·

I wonder what sort of IMU could that have been? Back then MEMS was not a thing, so how did that work? I am puzzled how they managed to target 200$

ChickeNES 6y ago
Actually, the first MEMS devices predate this by decades, though the first MEMS gyroscopes and accelerometers were actually developed around the same time as the Sega VR, though not available commercially. The article does link to the patent for the motion tracker used, and it's pretty odd (and not MEMS): https://patents.google.com/patent/US5526022A/en https://patents.google.com/patent/US5526022A/en
- krastanov 6y ago
  To quote from the patent: > The tilt sensor includes a transparent gas and a transparent viscous fluid in a spherical shell, a light emitting diode (LED) mounted at the top of the shell, and four photodetectors mounted at the bottom of the shell. As the tilt sensor is rotated the path of the light cone emanating from the LED and refracting at the gas/fluid interface is altered, thereby altering the intensity of light incident on the photodetectors. The magnitude of the light incident on the photodetectors is processed to provide the tilt angles. A thin transparent disk floats at the gas/fluid interface to damp surface waves caused by reorientation of the device. This is crazy
- RealityVoid 6y ago
  Yes, both you and ansible are right, raised good points, and I learned something today. My perspective was more in line with the fact that about decade ago, MEMS sensors got really cheap, so that enabled a whole slew of things that were inaccessible previously. Before, you didn't really have affordable, small options for these things. But TIL that the paths were prepared a long time in advance for this.
ansible 6y ago
MEMS accelerometers were definitely a thing. But commercial, low-cost MEMS was not yet a thing at that time. Motorola was rolling out their first product around that time, which was derived from military-grade hardware. That was for automotive use (airbag sensor).

ChickeNES 6y ago

Actually, the first MEMS devices predate this by decades, though the first MEMS gyroscopes and accelerometers were actually developed around the same time as the Sega VR, though not available commercially. The article does link to the patent for the motion tracker used, and it's pretty odd (and not MEMS): https://patents.google.com/patent/US5526022A/en https://patents.google.com/patent/US5526022A/en

krastanov 6y ago
To quote from the patent: > The tilt sensor includes a transparent gas and a transparent viscous fluid in a spherical shell, a light emitting diode (LED) mounted at the top of the shell, and four photodetectors mounted at the bottom of the shell. As the tilt sensor is rotated the path of the light cone emanating from the LED and refracting at the gas/fluid interface is altered, thereby altering the intensity of light incident on the photodetectors. The magnitude of the light incident on the photodetectors is processed to provide the tilt angles. A thin transparent disk floats at the gas/fluid interface to damp surface waves caused by reorientation of the device. This is crazy
RealityVoid 6y ago
Yes, both you and ansible are right, raised good points, and I learned something today. My perspective was more in line with the fact that about decade ago, MEMS sensors got really cheap, so that enabled a whole slew of things that were inaccessible previously. Before, you didn't really have affordable, small options for these things. But TIL that the paths were prepared a long time in advance for this.

ansible 6y ago

MEMS accelerometers were definitely a thing. But commercial, low-cost MEMS was not yet a thing at that time. Motorola was rolling out their first product around that time, which was derived from military-grade hardware. That was for automotive use (airbag sensor).