NewPing Library with Kalman-Filter (Ultrasonic Sensors) for Arduino

Written by Tim Eckel

https://bitbucket.org/teckel12/arduino-new-ping/wiki/Home

Modified for Teensy 3.0 & 3.1

https://github.com/PaulStoffregen/NewPing

http://forum.pjrc.com/threads/25907-Multiple-HCSR-04-Ultrasonic-sensors-on-teensy-3

New stuff added by Philip Burggasser:

• cm distance in float (ping_cm())
• cm distance in float with kalman filter (ping_cm_kalman())
• new cm measurement