The robot consists of two motors (rear) connected with a long axle to the frog’s legs, a single motor (front) that moves its tongue back and forth and an ultrasonic sensor that is used for finding distance proximity of obstacles. We attached two wheels to the robot’s front legs for greater balance and traction. All these are attached to the main brick, with a few connection reinforcements in order to keep it all together. The frog also has a touch sensor that moves the frog forward when pressed.
 
We connected the axles that were connected to each motor in order to form a large axle that runs through all the length of the back part. This allowed the robot have better foot synchronization and increased motor stability. 

For the tongue, a long Lego piece is connected to the motor with an axle. The piece is able to rotate freely along its axis, simulating the movement of a tongue. It is then attached through a series of small pieces to the frog’s body.

The robot’s program was designed with LabVIEW.  In short, the frog starts hopping when the touch sensor is triggered through a tap on its back. The frog then moves forward, until it senses something 30 cm away through its ultrasonic sensor. It immediately stops and the front motor starts, that moves the tongue forward and backwards in an intimidating fashion. The robot then hops in reverse to get away from the obstacle. It waits for a tap on its back to start moving again.