> electronic leveling

There are two common solutions: pendulum (gravity) and electric motor.
The pendulum solution is the most commonly used. It is simpler and cheaper. Its disadvantage is that it is sensitive to shock, requiring 2-5 seconds to return to position.
The electric motor version is much more expensive and slightly more precise. Its main advantage is that it is practically insensitive to vibration, and once leveled, it projects steadily.