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product:usb2lds:parameters

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product:usb2lds:parameters [2014/06/09 19:56]
xevel
product:usb2lds:parameters [2016/09/29 13:12]
xevel [Commands]
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 To set the parameters, the USB2LDS has to be in setup mode. To set the parameters, the USB2LDS has to be in setup mode.
  
-  * Start a serial terminal application (like [[http://​www.chiark.greenend.org.uk/​~sgtatham/​putty/!PuTTY]] or Arduino Serial Monitor) +  * Start a serial terminal application (like [[http://​www.putty.org/|PuTTY]] or Arduino Serial Monitor) 
-  * Open the Virtual serial port with a baud rate of //9600// (was //​1337// ​with first protos).+  * Open the Virtual serial port with a baud rate of //9600// (or //​1337// ​in the first prototypes).
   * Send '​a'​ to get back an overview of the current setup.   * Send '​a'​ to get back an overview of the current setup.
  
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-Default are FIXME+Default are Kp=0.05000, Ki=0.00010, Kd=0.00010
  
 === Turn rate setpoint === === Turn rate setpoint ===
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 Refer to [[http://​xv11hacking.wikispaces.com/​LIDAR+Sensor| LDS documentation,​ section "​Gotchas"​]] for info on what values are best. Refer to [[http://​xv11hacking.wikispaces.com/​LIDAR+Sensor| LDS documentation,​ section "​Gotchas"​]] for info on what values are best.
 +
 +Default is 19200 (=300 rpm, =5 rps, = 5Hz)
  
 === Feedforward === === Feedforward ===
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   * PROPORTIONAL : feedforward is a percentage of the RPM setpoint (adjusted with '​c'​and '​C'​) ​   * PROPORTIONAL : feedforward is a percentage of the RPM setpoint (adjusted with '​c'​and '​C'​) ​
  
-Default is FIXME+Default is PROPORTIONAL with a coef of 100.0.\\ 
 +Fixed feedforward default is 190.
  
 === Motor === === Motor ===
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 In some cases, badly tuned PID parameters can lead to instability. Given that the PID algorithm needs information on the actual turn rate of the sensor, and that the sensor only gives this information if it's turning, it is sometimes necessary to help the system to bet back to normal operation by giving the motor a little push. While this can be done physically by turning the sensor by hand, there is a command that briefly forces the motor to run (space). It might be necessary to send a lot of these commands at once (keep the key pressed) for the system to actually get back up. In some cases, badly tuned PID parameters can lead to instability. Given that the PID algorithm needs information on the actual turn rate of the sensor, and that the sensor only gives this information if it's turning, it is sometimes necessary to help the system to bet back to normal operation by giving the motor a little push. While this can be done physically by turning the sensor by hand, there is a command that briefly forces the motor to run (space). It might be necessary to send a lot of these commands at once (keep the key pressed) for the system to actually get back up.
  
 +By default, the motor starts to turn whenever the serial port is open.
  
 === Display === === Display ===
product/usb2lds/parameters.txt · Last modified: 2016/09/29 13:12 by xevel