Summary

The TDATA message type is intended for transferring 3D positions of surgical tools, markers etc. Those positions are often measured by optical, electromagnetic or other type of 3D position sensor continuously and transferred as series of messages. Since it is important for software that receives TDATA to control data flow, STT_TDATA query data type has interval field to control the frame rate of consecutive messages.

Message Types

TDATA

Data Type Description
NAME_1 char[20] Name (=Id) of the instrument/tracker
TYPE_1 8 bit unsigned 1: tracker, 2: 6D instrument (regular instrument), 3: 3D instrument (only tip of the instrument defined), 4: 5D instrument (tip and handle are defined, but not the normal vector)
-- 8 bit unsigned Reserved
MATRIX_1 32 bit float 12 values like in TRANSFORM message
...
NAME_N char[20] Name (=Id) of the instrument/tracker
TYPE_N 8 bit unsigned 1: tracker, 2: 6D instrument (regular instrument), 3: 3D instrument (only tip of the instrument defined), 4: 5D instrument (tip and handle are defined, but not the normal vector)
-- 8 bit unsigned Reserved
MATRIX_N 32 bit float 12 values like in TRANSFORM message

GET_TDATA

Data Type Description

STT_TDATA

Data Type Description
Resolution 32 bit unsigned Minimum time between two frames. Use 0 for as fast as possible. If e.g. 50 ms is specified, the maximum update rate will be 20 Hz.
Coordinate system name char[32] Coordinate system to use. Can be empty for default coordinate system. (not included if action = 2)
  • All tracking data from one frame is included.
  • Invisible/unavailable trackers/instruments are not included.
  • Easy to develop. Sample pseudo code: while(true) { recv(trackingdata); updateView(trackingdata); }
  • Usually the tracking data will be sent using the standard coordinate system, which is also used for POINT, IMAGE, … But this does only work after patient registration. Therefore the body of START_PUSH has an optional field for specifing the coordinate system “CAMERA”. To switch back to the standard coordinate system, one has to send STOP_PUSH and afterwards START_PUSH without explicitly specifing the camera coordinate system.

STP_TDATA

Data Type Description

RTS_TDATA

Data Type Description
Status 8 bit unsigned 0: Success 1: Error

Implementations

The TDATA message type is implemented in the following source code.

Contributors

  • Alexander Schaal