The sensor outputs UDP packets via Ethernet.The packet contains a header, a data payload of firing data, and status data. The upper block of 32 laser distance and intensity data is collected first followed by the lower block laser distance and intensity data. The data packet is then combined with status and header data in a UDP packet transmitted over Ethernet.
The HDL-64S3D sensor with Dual Return Mode sends a pair of data blocks for each azimuth angle firing. The odd numbered blocks (1, 3, ..., 9, 11) contain either the strongest or second-strongest return and the even numbered blocks (0, 2, ..., 8, 10) contain the last return. If the strongest return is also the last return, then the second-strongest return is provided. If only one return was detected, the data will be identical in the even|odd block pairs (0|1, 2|3, 4|5, 6|7, 8|9, 10|11).
The HDL-64S3S sensor in Single Return Mode sends a single data block for each azimuth angle firing.
The status data always contains a GPS 4-byte timestamp representing microseconds from the top of the hour. In addition, the status data contains one type of data. The other status data rotates through a sequence of different pieces of information.
Each of the sensor’s lasers is fixed with respect to vertical angle and offset to the rotational index data provided in each packet. For each data point issued by the sensor, rotational and horizontal correction factors are applied to determine the location of the point in 3D space.Intensity and distance offsets are also applied.