Robbi, Tobbi und das Fliewatüüt is a German television series for children. It showed the adventures of a pupil called Tobias (nicknamend Tobbi) who accompanied by his robot

Robot

A robot is a mechanical or virtual intelligent agent that can perform tasks automatically or with guidance, typically by remote control. In practice a robot is usually an electro-mechanical machine that is guided by computer and electronic programming. Robots can be autonomous, semi-autonomous or...

 (nicknamed Robbi) travels in a self-designed all-in-one vehicle

Vehicle

A vehicle is a device that is designed or used to transport people or cargo. Most often vehicles are manufactured, such as bicycles, cars, motorcycles, trains, ships, boats, and aircraft....

 for an exam which involves riddles all over world.

He calls his apparatus (which runs on juice from red raspberries) "Flie-wa-tüüt" because:

1. it can fly (in German: fliegen)
2. it can travel on water (in German Wasser)
3. it can be used as a car (and as such is has a klaxon making the sound "tüüt")

During their adventures (animated by puppeteer Albrecht Roser

Albrecht Roser

Albrecht Roser was a German master puppeteer based in Stuttgart, Germany.-Background and artistic contribution:...

 and his team) young inventor Tobbi and his pilot Robbi have to tackle many challenges.

The mini series was based on a book by German author Boy Lornsen

Boy Lornsen

Boy Lornsen was a German sculptor and author of children's literature, writing both in Standard German and in Platt....

, used already back then Chroma key

Chroma key

Chroma key compositing is a technique for compositing two images together. A color range in the top layer is made transparent, revealing another image behind. The chroma keying technique is commonly used in video production and post-production...

technology and had countless re-runs.