Upkie has environments compatible with the Gymnasium API:

Environment ID	Backend	Action and observation spaces
`Upkie-Genesis-Pendulum`	Genesis	Pendulum
`Upkie-Genesis-Servos`	Genesis	Servos
`Upkie-Mock-Pendulum`	Mock	Pendulum
`Upkie-Mock-Servos`	Mock	Servos
`Upkie-PyBullet-Pendulum`	PyBullet	Pendulum
`Upkie-PyBullet-Servos`	PyBullet	Servos
`Upkie-Spine-Pendulum`	Spine	Pendulum
`Upkie-Spine-Servos`	Spine	Servos

While each environment has its own observation and action spaces, all of them also report full spine observations in their info dictionaries.