Does LEGO WeDo 9580 really have a sound sensor? Yes and no. The LEGO WeDo basic set comes only with 2 sensors, a "motion" sensor (actually distance sensor) and tilt sensor. No sound sensor. The WeDo Resource Set 9585 also do not come with any sensor at all.
So where does this WeDo sound sensor come from. Actually the computer's mike (microphone) with the software sound input block together can serve as a sound sensor. The program below comprising START block, Display block with microphone input, WAIT block so that the display don't change so fast, and the REPEAT loop
The video below shows the number on the screen display changing with the sound loudness. Note: the values ranged from 0 to 10:
Video demonstrating voice command MOVE in 41 languages to make LEGO Power Function motor move using LEGO Wedo robotic program. Earlier post with explanation and program at Sound activated motor.
Footnote: pronunciation of MOVE in 41 languages made with Google Translate:
This post will demonstrate how to program a LEGO Power Function motor to move on sound input. We do not need a specific sensor to do this but it will use the computer microphone as the sensor to pick up sound. The Wedo program will consist of a START block, Wait for block, Motor turn this way block, Motor turn for 4 seconds block, Wait block and Repeat block plus a sound input as shown below:
On clicking START, the Wait block will wait for input of sound from the "sound sensor" (computer mike). On hearing sound, the next block turn the motor this way (clockwise) and following block set the motor to turn 3 seconds. The final WAIT 2 seconds block have to be added in to force an interval before the program loop back to the START to repeat. If this is not added, the sound of the motor turning itself will then trigger to motor to move again and the program will go through continuous looping without waiting for the intended sound to start.
See video below. Also see how we can use this to have a Sound controlled car which moves on a sound command eg. clap hands.
Application: Sound controlled car
There is an earlier post about Building computer controlled car. All we need to do to have a sound controlled car is to connect the motor shown below to the computer and setup the above program to make the car move on sound command such as clap of the hands:
Connect motor to computer plus above program to make car move on sound input
This post will show how a motion (distance) sensor can be used to control the speed of a motor and via a crank, the speed at which a goalkeeper moves. The original construction as given by Lego is as shown below (the guidance of parents or grandparents is probably needed for this post):
Lego Wedo goalkeeper game construction as per Lego building instructions
with motion sensor looking different direction from goalkeeper
Look at the direction the motion sensor is looking and the direction the goalkeeper is looking. The motion sensor is looking the wrong way. So we need to modify the setup so that the motion sensor is looking the same way as the goalkeeper - at the striker (ball kicker). Below shows the photo where the sensor is looking at the same direction as the goalkeeper:
For this tilt sensor experiment, we need to add a START block followed by a DISPLAY BLOCK (alphanumeric) with a TILT SENSOR INPUT. Then add a REPEAT block to make the DISPLAY BLOCK to keep checking for input from the TILT SENSOR INPUT block (see screenshot below):
Wedo Tilt Sensor Experiment
LEGO Wedo Tilt Sensor Experiment program
Observe the ALPHANUMERIC DISPLAY window as you tilt the sensor from horizontal to tilt left, then tilt right, from horizontal to tilt upward then tilt downward. You will see the display window changes from zero to zero to 4 then 8 as we tilt the sensor from tilt left then tilt right. We will also observe the display window changes from zero to 2 then 10 as we tilt from horizontal to upward then downward.
Depending on how it is tilted, the sensor will output different values as follows:
Horizontal: 0
Up: 2
Down: 10
Left: 8
Right: 4
The tilt sensor is useful for detecting tilt for various WeDo models like the rocking sailboat or airplane.
A good illustration of how the tilt sensor can be used would be for 2 legged walking robot for sensing tilt and correspondingly move motor or motors in such a way as to keep balance so the walking robot does not fall down.
The LEGO WeDo robotic set (Produce Number 9580) has 2 sensors, a tilt sensor and a distance sensor (often described as a motion sensor).
Let's do some experiment with the distance sensor. Connect distance sensor to the hub, connect hub to computer USB port, Open Wedo software to add program, add a START button, add a "Numeric screen output", add a motion sensor as input to the "Numeric screen output", add a loop to repeat (see photo).
See photo of the experiment setup. The experiment showed that the output value of the distance sensor changes from 0 when it is far away to 10 when it is nearest to the sensor. See video.
Photo distance sensor
LEGO Wedo distance sensor (motion sensor)
WeDo program to experiment with distance sensor
LEGO Wedo program steps to experiment with distance sensor
Experiment setup
Lego WeDo distance sensor experiment setup
Video showing experiment to show value output of distance sensor
