RoboSense RS-Ruby Lite, User Manual, Page: 22 / 104

RS-Ruby Lite Users’ Manual
17
7 Key Specifications
7.1 Return Mode
7.1.1 The Principle of Return Mode
Due to laser divergence, laser pulse could hit more than one object after one single emission.
The strongest return indicates the return signal that owns the strongest energy. The last return
indicates the return signal that lastly comes back to sensor. For the dual return, both the two
return signals are received by sensor.
There are three return modes on RS-Ruby Lite: Strongest Return, Last Return and Dual
Return Mode. If return mode is set up to the strongest return mode, only the strongest return
signal is seen as available signal in distance calculation. Similarly, if the setting is the last
return mode, only the last return signal is used to calculate distance. Dual return mode
includes the distances of both the two return modes mentioned before.
Notice: only if the distance of two different objects is larger than 1m, those cannot be
distinguished in the dual return.
7.1.2 Strongest Return
When the laser pulse hits on a near object, this return signal could be considered as strongest
return signal.
7.1.3 Strongest, Last and Dual Return Signal
After the laser pulse hits two flat walls at different distance, two return signal will appear in dual
return mode. There will be two consequences:
1) The strongest return signal is not last return signal, it will return strongest and last signal.
2) The strongest return signal is the last return signal, it will return a sub-strongest signal and
the strongest return signal.
7.1.4 Return Mode Flag
The factory default setting of return mode on RS-Ruby Lite is Last Return Mode. The
relative return mode setting refers to “Return Mode” in appendix A. In DIFO packet, the
300th. Byte indicates the return mode flag:
Table 8: Flag and Return Mode.
Flag Return Mode
03 Dual Return Mode
02 Last Return Mode
01 Strongest Return Mode
7.2 Phase Lock
The Phase Lock feature can be used to make the sensor rotating to the specific position when
the PPS signal is triggered. To operate correctly, the PPS signal must be present and locked
stable.