This is an open source project available on GitHub here:
https://github.com/kevine711/Android-Oreo-Vibration-Builder

DEVELOPER USE ONLY - There is no use case for a general user unless you just want to play with vibration profiles.

I created this project to help developers feel out different profiles you can create with the new VibrationEffect in API 26.

I'm using the below method. In app, timings are referred to as "delay" and amplitudes as "intensity." You can create a comma separated list of delays and intensities and run the profile to feel the effect. Some examples are provided.
VibrationEffect createWaveform (long[] timings,
int[] amplitudes,
int repeat)