Design Challenge

Design and build a robot in 20 weeks. 


Creating enthusiasm under children for robotics is of great importance. In an interdisciplinary team a modular robot was designed to introduce young children into the world of robotics.

During the minor Robotics at the Delft University of Technology, Flip was designed and build. Flip is a modular robot aimed to introduce children in the world of robotics. The idea was to enable children to use robotics, without them needing to program the robot. Children would be able to insert different legs into a body. In this way they could see the effect of changing an extremity on the robots behavior.

Early cardboard prototype of a modular robot.

Flip – The friendly robot

Flip was designed for children. Introducing them to robotics in an easy way. The idea was to enable children to use a body block in which different legs can be inserted. To give the design more depth, a emotion block (heart) was added. The function of this block is to give an emotion to the robot which in turn determines the behaviour. Flip was born. Flip consists of three different elements: (1) The heart, (2) The body, (3) The extremities.

Sketches of the robot during the project.
Render of the final design of Flip, the modular robot.


The Heart gives life to Flip. The colour of the heart determines the emotion and thus the behaviour of the robot. Yellow makes Flip react happy, while green makes him afraid. The emotion is reflected in the behaviour of Flip; e.g. driving away from you when he is fearful. This allows children to program Flip by only changing its heart.


Three different extremities where created: a wheel, half a wheel and a cross-wheel. Using a DIN connector, the extremities are connected to the body. A modified servomotor rotates the wheel or leg. Upto 4 different extremities can be attached to the body.

Exploded view of the extremity


The heart and the different extremities can be connected to the body to create a functioning robot. To react on its environment Flip was given different sensors; microphone, ultrasonic range and LDR. Sounds can be created by the speaker in the bottom of the body. To indicate the battery status an LED has been used.

Exploded view of Flip

Integrated Design

After 6 months of designing, prototyping and testing, a fully working prototype was created. Using additive manufacturing and lasercutting the protoype was created. The body was created from PLA, the heart and extremities out of ABS and the internal mounting plate out of PMMA.

Photo of the final prototype of Flip.
  • Weight 1150 gr
  • 220 x 200 x 100 mm
  • 4 emotions
  • 3 different extremities
  • material: ABS, PLA, PMMA
  • LiPo 7,4 V
  • 18.294 lines of code