Sonars¶
Specifications¶
Sonar: 2 emitters, 2 receivers.
NAO is equipped with two ultrasonic sensors (or sonars) which allow it to estimate the distance to obstacles in its environment.
| NAO V5 |
|
| NAO V4 and V3.x |
The detection range goes from 25 cm to 255 cm, but under 25 cm there is no distance information, the robot only knows that an object is present. |
Location¶
Position relative to the Torso frame.
| Sonar name | X(m) | Y(m) | Z(m) | WX(rd)[deg]* | WY(rd)[deg]* | WZ(rd)[deg]* |
|---|---|---|---|---|---|---|
| US sensor 1 | 0.0537 | -0.0341 | 0.0698 | 0.0 | -0.1745 [-10.0] | -0.3490 [-20.0] |
| US sensor 2 | 0.0477 | -0.0416 | 0.0509 | 0.0 | 0.2618 [15.0] | -0.4363 [-25.0] |
To access values by using ALMemory key names, see: Sonar Actuator and Sensors.
Note
We adopt the roll, pitch and yaw notation for angle representation. So, to construct an homogeneous transform with rotation (Wx,Wy,Wz) use T=rotZ(Wz)*rotY(Wy)*rotX(Wx)
- US sensor 3 is symmetrical to US sensor 1 with respect to sagittal plane of the robot.
- US sensor 4 is symmetrical to US sensor 2 with respect to sagittal plane of the robot.