Pepperl+Fuchs IMUF99 B20 Series Manual page 9

Inertial Measurement Unit IMUF99*B20
Product Description
Body fixed coordinate system (intrinsic or co-rotating) for Euler angle zy'x''
Figure 2.3
Body fixed coordinate system (intrinsic or co-rotating) for P+F angle INZ
Figure 2.4
Gravity Flag
The IMU measures the acceleration, yaw rate and angle in each of 3 axis. Regardless of the
current position of the sensor in space, the acceleration and yaw rate values = rotation rate val-
ues are always reliably available. A reliable angle output per measuring axis depends on the
current position of the sensor in space.
A change in angle around the gravitational vector, which is always vertical, can't be measured.
If a measuring sensor axis is parallel to the gravitational vector (±5°), then this axis does not
provide reliable angle values and must be ignored. The Gravity Flag (GF) offers help for this.
The sensor automatically detects whether a sensor axis is parallel to the gravitational vector
and shows this in the status of the Gravity Flag (GF). Accordingly, it is always displayed for
each angle value as to whether it can be used.
Application Flag
Independent limits can be set for the X, Y and Z axes of the acceleration, rotation rate and
angle measurement axis. If these limits are exceeded, this is indicated in the switching status of
the Application Flags (AF). The parameters 0x69 to 0x8C are used to set the application flags
(AF). The status of the application flag (AF) is displayed in byte 7 of PDO 0 (MappingID 9) for
acceleration, PDO 1 (MappingID 10) for yaw rate and PD0 5 (MappingID 11) for angle.
Y
−
Roll
+
Y
−
Roll
+
Z
+ −
X
+
Pitch
−
Yaw
Z
+
−
X
+
Pitch
−
Yaw
9