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doc:lps:toda3 [2018-06-15 08:08]
kristoffer 		doc:lps:toda3 [2018-06-15 08:51]
kristoffer
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 For instance ''make "EXTRA_CFLAGS=-DLPS_TDOA_USE_V3 -DLPS_TDOA_ENABLE -DLPS_2D_POSITION_HEIGHT=1.2"'' if the tag will be located at 1.2 meters height. For instance ''make "EXTRA_CFLAGS=-DLPS_TDOA_USE_V3 -DLPS_TDOA_ENABLE -DLPS_2D_POSITION_HEIGHT=1.2"'' if the tag will be located at 1.2 meters height.
  
-===== Longer range =====+===== Longer range and lower bitrate =====
  
 In this mode the UWB bitrate is lower and the data of messages can be read at a longer distance. The packet rate will be reduced though. In this mode the UWB bitrate is lower and the data of messages can be read at a longer distance. The packet rate will be reduced though.
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 It is possible to use a longer preamble, this will also reduce packet rate. There is no compile flag for this setting, it requires some code modifications in the Crazyflie and the anchors. It is possible to use a longer preamble, this will also reduce packet rate. There is no compile flag for this setting, it requires some code modifications in the Crazyflie and the anchors.
 +The preamble is used by the anchor radios to detect messages and a longer preamble increase the probability and thus the useful distance.
 +Note that the radios might detect the preamble but fail at reading the data of the packet (see lower bitrate above). The "SFD" LED on the anchor indicates if a preamble has been detected by the radio.
  
 ==== The Crazyflie ==== ==== The Crazyflie ====
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 example: ''python3 tools/sniffer/sniffer_binary.py /dev/tty.usbmodem1421 yaml | python3 tools/sniffer/tdoa3_decoder.py 2 3'' example: ''python3 tools/sniffer/sniffer_binary.py /dev/tty.usbmodem1421 yaml | python3 tools/sniffer/tdoa3_decoder.py 2 3''
  
-==== Time of flight ====+==== Time of flight and anchor to anchor distance ====
  
 By piping the TDoA 3 data into the TOF tool, the measured anchor to anchor distances will be displayed. By adding the 'm' argument the output will be in meters instead of UWB clock ticks. By piping the TDoA 3 data into the TOF tool, the measured anchor to anchor distances will be displayed. By adding the 'm' argument the output will be in meters instead of UWB clock ticks.
  
 example: ''python3 tools/sniffer/sniffer_binary.py /dev/tty.usbmodem1421 yaml | python3 tools/sniffer/tdoa3_decoder.py | python3 tools/sniffer/tdoa3_tof.py m'' example: ''python3 tools/sniffer/sniffer_binary.py /dev/tty.usbmodem1421 yaml | python3 tools/sniffer/tdoa3_decoder.py | python3 tools/sniffer/tdoa3_tof.py m''
 +
 +==== Setting anchor positions ====
 +
 +Anchor positions can be set by the python client but it only supports ids 0-7. If you want to use more anchors there is a tool that can be used.
 +
 +The tool uses a Crazyflie as a bridge to transmit UWB messages to the anchors. When it is started it transmits positions for all anchors over and over,
 +
 +The tool is somewhat hackish and could use some updates, for instance the Crazyflie radio address is hardcoded in the script. Be prepared to modify the script...
 +
 +  * Create a file with your anchor positions, see tools/lpp/positions_example.yaml
 +  * Start the Crazyflie
 +  * Pipe the position file into the tool ''cat my_position_file.yaml | python3 tools/lpp/set_positions.py''
 +  * Move the Crazyflie close to all anchors to transfer the positions
 +
 +
doc/lps/toda3.txt · Last modified: 2020-05-12 14:08 by kimberly

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