With the use of ultrasound the LEGO Mindstorms EV3 & NXT Ultrasonic sensors could detect the distance to an object. You can use it in many different ways most of them very interesting and fun. Some of them a little more challenging, but rewarding.
Mintonet (engl. Mintonette) comes from the name of the first iteration of volleyball.
The robot can move only forward and backward, without turning, with the help of a large EV3 motor. Another large motor is used to shoot. The robot uses an EV3 ultrasonic sensor to detect its partner and throw a ball at it.
Mintonette comes from the first iteration of Volleyball with the same name.
The robot uses two EV3 Touch sensors to control the turret left and right. It uses the EV3 Color sensor to trigger the shooting mechanism, which consists of an EV3 Large motor which pulls a lever to shoot a ball.
Building instructions for a LEGO robot that shoots 40 mm ping pong balls. The shooting mechanism is powered by two EV3 Large motors, while the whole mechanism is rotated by a medium motor. The robot can store up to 6 ping pong balls and has a Ultrasonic Sensor to detect targets.
This frame holds the motor and ev3 brick used in the catapult. The frame is placed on top of the rotating base and thus could be easily rotated. The brick could be both NXT and EV3
These are building instruction for a working automatic catapult with a motor and a touch sensor.