Installation Alignment Packet

Installation Alignment Packet
Packet ID				185
Length				73
Read / Write				Read / Write
Field #	Bytes Offset	Data Type	Size	Description
1	0	u8	1	Permanent
2	1	fp32	4	Alignment DCM[0][0]
3	5	fp32	4	Alignment DCM[0][1]
4	9	fp32	4	Alignment DCM[0][2]
5	13	fp32	4	Alignment DCM[1][0]
6	17	fp32	4	Alignment DCM[1][1]
7	21	fp32	4	Alignment DCM[1][2]
8	25	fp32	4	Alignment DCM[2][0]
9	29	fp32	4	Alignment DCM[2][1]
10	33	fp32	4	Alignment DCM[2][2]
11	37	fp32	4	Operating Orientation
12	41	fp32	4	Reserved (set to 0)
13	45	fp32	4	Reserved (set to 0)
14	49	fp32	4	Reserved (set to 0)
15	53	fp32	4	Reserved (set to 0)
16	57	fp32	4	Reserved (set to 0)
17	61	fp32	4	Reserved (set to 0)
18	65	fp32	4	Reserved (set to 0)
19	69	fp32	4	Reserved (set to 0)

Installation Alignment Packet

Alignment DCM

The alignment DCM (Direction Cosine Matrix) is used to represent an alignment offset of Subsonus from its standard alignment. A DCM is used rather than Euler angles for accuracy reasons. To convert Euler angles to DCM, use the formula below with angles in radians.

DCM[0][0] = cos(heading) * cos(pitch)

DCM[0][1] = sin(heading) * cos(pitch)

DCM[0][2] = -sin(pitch)

DCM[1][0] = -sin(heading) * cos(roll) + cos(heading) * sin(pitch) * sin(roll)

DCM[1][1] = cos(heading) * cos(roll) + sin(heading) * sin(pitch) * sin(roll)

DCM[1][2] = cos(pitch) * sin(roll)

DCM[2][0] = sin(heading) * sin(roll) + cos(heading) * sin(pitch) * cos(roll)

DCM[2][1] = -cos(heading) * sin(roll) + sin(heading) * sin(pitch) * cos(roll)

DCM[2][2] = cos(pitch) * cos(roll)