Adjust scale for acc and gyro

[iory]

Related to #14
This PR sets the scales for gyro and acc to meters and degrees per second.

test code

#!/usr/bin/env python
import rospy
from sensor_msgs.msg import Imu
import numpy as np


def callback(msg):
    angular_norm = np.sqrt(msg.angular_velocity.x ** 2
                           + msg.angular_velocity.y ** 2
                           + msg.angular_velocity.z ** 2)

    acc_norm = np.sqrt(msg.linear_acceleration.x ** 2
                       + msg.linear_acceleration.y ** 2
                       + msg.linear_acceleration.z ** 2)

    if acc_norm > 1.4:
        rospy.loginfo("Detect impact {}".format(acc_norm))


def listener():
    rospy.init_node('listener', anonymous=True)
    rospy.Subscriber("imu", Imu, callback, queue_size=10)
    rospy.spin()

if __name__ == '__main__':
    listener()

[INFO] [1705382302.899259]: Detect impact 1.4350709673397826
[INFO] [1705382304.198912]: Detect impact 2.5297361374467084
[INFO] [1705382305.154315]: Detect impact 2.13326023903858
[INFO] [1705382321.513858]: Detect impact 1.4318167515840723
[INFO] [1705382321.616729]: Detect impact 1.6437944926118708
[INFO] [1705382321.776413]: Detect impact 1.740089856369743
[INFO] [1705382322.314692]: Detect impact 1.5967120085012034
[INFO] [1705382327.652455]: Detect impact 3.636909679445078
[INFO] [1705382329.275340]: Detect impact 2.246232104121857
[INFO] [1705382330.204769]: Detect impact 1.537381589994245