Twist¶
We already know how to make PiCrawler assume a specific pose, the next step is to combine the poses to form a continuous action.
Here, PiCrawler’s four feet are up and down in twos, jumping with the music.
Run the Code
cd /home/pi/picrawler/examples
sudo python3 twist.py
Code
Note
You can Modify/Reset/Copy/Run/Stop the code below. But before that, you need to go to source code path like picrawler\examples
. After modifying the code, you can run it directly to see the effect.
from picrawler import Picrawler
from time import sleep
from robot_hat import Music
music = Music()
crawler = Picrawler([10,11,12,4,5,6,1,2,3,7,8,9])
#crawler.set_offset([0,0,0,0,0,0,0,0,0,0,0,0])
def twist(speed):
## [right front],[left front],[left rear],[left rear]
new_step=[[50, 50, -80], [50, 50, -80],[50, 50, -80], [50, 50, -80]]
for i in range(4):
for inc in range(30,60,5):
rise = [50,50,(-80+inc*0.5)]
drop = [50,50,(-80-inc)]
new_step[i]=rise
new_step[(i+2)%4] = drop
new_step[(i+1)%4] = rise
new_step[(i-1)%4] = drop
crawler.do_step(new_step,speed)
def main():
music.background_music('./musics/sports-Ahjay_Stelino.mp3')
music.music_set_volume(20)
while True:
twist(speed=100)
if __name__ == "__main__":
main()
How it works?
In this code, you need to pay attention to this part:
def twist(speed):
## [right front],[left front],[left rear],[right rear]
new_step=[[50, 50, -80], [50, 50, -80],[50, 50, -80], [50, 50, -80]]
for i in range(4):
for inc in range(30,60,5):
rise = [50,50,(-80+inc*0.5)]
drop = [50,50,(-80-inc)]
new_step[i]=rise
new_step[(i+2)%4] = drop
new_step[(i+1)%4] = rise
new_step[(i-1)%4] = drop
crawler.do_step(new_step,speed)
Simply put, it uses two layers of for loops to make the new_step
array produce continuous and regular changes, and at the same time, crawler.do_step()
executes the posture to form a continuous action.
You can intuitively get the coordinate value array corresponding to each pose from Adjust Posture.
In addition, the example also played background music. The implementation method is as follows.
Play music by importing the following libraries.
from robot_hat import Music
Declare a Music object.
music = Music()
Play the background music in the picrawler/examples/musics
directory and set the volume to 20. You can also add music to the musics
folder via Filezilla Software.
music.background_music('./musics/sports-Ahjay_Stelino.mp3')
music.music_set_volume(20)
Note
You can add different sound effects or music to musics
or sounds
folder via Filezilla Software.