Velocity, acceleration and jerk
From wikiluntti
Introduction
The Newton force rule states that force and acceleration are proportionally related. Is it possible to accelerate without noticing that? The method is used in elevators, for example, and hopefully in modern (electric) cars.
We consider the acceleration the robot is subjected to while accelerating it using different acceleration functions.
Robot
Almost any robot will be ok, we use Asimov 2/ Verne.
Sensor
The Vernier acceleration sensor with NXT Adapter is used. The sensor is attached to port number 4.
Very simple test program to see what are the measured values is shown below. The values are in arbitrary scale, and need to be normalized. We found, that the
#!/usr/bin/env python3
# https://sites.google.com/site/ev3devpython/
from ev3dev2.sensor import *
from ev3dev2.sensor import INPUT_4
import time
import os
os.system('setfont Lat15-TerminusBold32x16') # Try this larger font
p = Sensor( INPUT_4 )
p.mode="ANALOG-1"
def measureAcc(p):
acc = p.value(0)
return acc
f = open('acc.csv',"w")
writer = csv.writer(f)
tstep = 0.001
while True:
acc = measureAcc(p)
print( acc )
writer.writerow((time.time(), acc ))
time.sleep( tstep )