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MPU-9150. All in one kit. Gyro, Acceleration and Compass.
Links: Amazon: http://www.amazon.de/GY-9150-MPU-9150-Achsen-Kompass-Accelerometer-SE05014/dp/B00VRJEA7C/ref=sr_1_1?ie=UTF8&qid=1430578388&sr=8-1&keywords=MPU-9150
Specification: http://www.invensense.com/mems/gyro/documents/PS-MPU-9150A-00v4_3.pdf
Cost: 20.59€
Operating Voltage Supply: 2.4V-3.46V
Logic Supply Voltage: 1.8V +- 5% or VDD
Communication via I2C-Bus
Proximity Sensors
4-Pin Ultrasonic-Module HC-SR04
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