linux - 如何从串口 SICK LMS200 读取数据？

Question

我想通过串口从 SICK LMS200 激光雷达扫描仪读取数据。我可以看到串行端口为/dev/ttyUSB0。我只是不知道如何从中获取数据。

我尝试使用工具箱手册中所示的手动安装在 Ubuntu 14.04.3 LTS 下安装 The Sick LIDAR Matlab/C++ Toolbox。

我解压文件:

$tar -xzvf sicktoolbox-1.0.1.tar.gz

这就是我在运行 ./configure 后得到的(不确定它是否有帮助)

me@MyPC:~/smetiste/Sick/sicktoolbox-1.0.1$ ./configure 
checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... /bin/mkdir -p
checking for gawk... gawk
checking whether make sets $(MAKE)... yes
checking for g++... g++
checking for C++ compiler default output file name... a.out
checking whether the C++ compiler works... yes
checking whether we are cross compiling... no
checking for suffix of executables... 
checking for suffix of object files... o
checking whether we are using the GNU C++ compiler... yes
checking whether g++ accepts -g... yes
checking for style of include used by make... GNU
checking dependency style of g++... gcc3
checking for gcc... gcc
checking whether we are using the GNU C compiler... yes
checking whether gcc accepts -g... yes
checking for gcc option to accept ISO C89... none needed
checking dependency style of gcc... gcc3
checking how to run the C preprocessor... gcc -E
checking for a BSD-compatible install... /usr/bin/install -c
checking whether ln -s works... yes
checking whether make sets $(MAKE)... (cached) yes
checking build system type... i686-pc-linux-gnu
checking host system type... i686-pc-linux-gnu
checking for a sed that does not truncate output... /bin/sed
checking for grep that handles long lines and -e... /bin/grep
checking for egrep... /bin/grep -E
checking for ld used by gcc... /usr/bin/ld
checking if the linker (/usr/bin/ld) is GNU ld... yes
checking for /usr/bin/ld option to reload object files... -r
checking for BSD-compatible nm... /usr/bin/nm -B
checking how to recognise dependent libraries... pass_all
checking for ANSI C header files... yes
checking for sys/types.h... yes
checking for sys/stat.h... yes
checking for stdlib.h... yes
checking for string.h... yes
checking for memory.h... yes
checking for strings.h... yes
checking for inttypes.h... yes
checking for stdint.h... yes
checking for unistd.h... yes
checking dlfcn.h usability... yes
checking dlfcn.h presence... yes
checking for dlfcn.h... yes
checking how to run the C++ preprocessor... g++ -E
checking for g77... no
checking for xlf... no
checking for f77... no
checking for frt... no
checking for pgf77... no
checking for cf77... no
checking for fort77... no
checking for fl32... no
checking for af77... no
checking for xlf90... no
checking for f90... no
checking for pgf90... no
checking for pghpf... no
checking for epcf90... no
checking for gfortran... no
checking for g95... no
checking for xlf95... no
checking for f95... no
checking for fort... no
checking for ifort... no
checking for ifc... no
checking for efc... no
checking for pgf95... no
checking for lf95... no
checking for ftn... no
checking whether we are using the GNU Fortran 77 compiler... no
checking whether  accepts -g... no
checking the maximum length of command line arguments... 32768
checking command to parse /usr/bin/nm -B output from gcc object... ok
checking for objdir... .libs
checking for ar... ar
checking for ranlib... ranlib
checking for strip... strip
checking if gcc supports -fno-rtti -fno-exceptions... no
checking for gcc option to produce PIC... -fPIC
checking if gcc PIC flag -fPIC works... yes
checking if gcc static flag -static works... yes
checking if gcc supports -c -o file.o... yes
checking whether the gcc linker (/usr/bin/ld) supports shared libraries... yes
checking whether -lc should be explicitly linked in... no
checking dynamic linker characteristics... GNU/Linux ld.so
checking how to hardcode library paths into programs... immediate
checking whether stripping libraries is possible... yes
checking if libtool supports shared libraries... yes
checking whether to build shared libraries... yes
checking whether to build static libraries... yes
configure: creating libtool
appending configuration tag "CXX" to libtool
checking for ld used by g++... /usr/bin/ld
checking if the linker (/usr/bin/ld) is GNU ld... yes
checking whether the g++ linker (/usr/bin/ld) supports shared libraries... yes
checking for g++ option to produce PIC... -fPIC
checking if g++ PIC flag -fPIC works... yes
checking if g++ static flag -static works... yes
checking if g++ supports -c -o file.o... yes
checking whether the g++ linker (/usr/bin/ld) supports shared libraries... yes
checking dynamic linker characteristics... GNU/Linux ld.so
checking how to hardcode library paths into programs... immediate
appending configuration tag "F77" to libtool
checking for gnuplot... no
configure: WARNING: *** gnuplot not found, some examples will not be built.
checking for doxygen... no
configure: WARNING: doxygen not found - will not generate any doxygen documentation
checking for perl... /usr/bin/perl
checking for the pthreads library -lpthreads... no
checking whether pthreads work without any flags... no
checking whether pthreads work with -Kthread... no
checking whether pthreads work with -kthread... no
checking for the pthreads library -llthread... no
checking whether pthreads work with -pthread... yes
checking for joinable pthread attribute... PTHREAD_CREATE_JOINABLE
checking if more special flags are required for pthreads... no
checking for ANSI C header files... (cached) yes
checking arpa/inet.h usability... yes
checking arpa/inet.h presence... yes
checking for arpa/inet.h... yes
checking fcntl.h usability... yes
checking fcntl.h presence... yes
checking for fcntl.h... yes
checking netinet/in.h usability... yes
checking netinet/in.h presence... yes
checking for netinet/in.h... yes
checking for string.h... (cached) yes
checking sys/ioctl.h usability... yes
checking sys/ioctl.h presence... yes
checking for sys/ioctl.h... yes
checking sys/socket.h usability... yes
checking sys/socket.h presence... yes
checking for sys/socket.h... yes
checking sys/time.h usability... yes
checking sys/time.h presence... yes
checking for sys/time.h... yes
checking termios.h usability... yes
checking termios.h presence... yes
checking for termios.h... yes
checking for unistd.h... (cached) yes
checking linux/serial.h usability... yes
checking linux/serial.h presence... yes
checking for linux/serial.h... yes
checking for stdbool.h that conforms to C99... yes
checking for _Bool... yes
checking for an ANSI C-conforming const... yes
checking for inline... inline
checking whether byte ordering is bigendian... no
checking whether time.h and sys/time.h may both be included... yes
checking for int16_t... yes
checking for uint16_t... yes
checking for uint32_t... yes
checking for uint8_t... yes
checking whether gcc needs -traditional... no
checking sys/select.h usability... yes
checking sys/select.h presence... yes
checking for sys/select.h... yes
checking for sys/socket.h... (cached) yes
checking types of arguments for select... int,fd_set *,struct timeval *
checking return type of signal handlers... void
checking for gettimeofday... yes
checking for memset... yes
checking for select... yes
checking for socket... yes
checking for strcasecmp... yes
configure: creating ./config.status
config.status: creating Makefile
config.status: creating c++/Makefile
config.status: creating c++/examples/Makefile
config.status: creating c++/examples/ld/Makefile
config.status: creating c++/examples/ld/ld_config/Makefile
config.status: creating c++/examples/ld/ld_config/src/Makefile
config.status: creating c++/examples/ld/ld_more_config/Makefile
config.status: creating c++/examples/ld/ld_more_config/src/Makefile
config.status: creating c++/examples/ld/ld_multi_sector/Makefile
config.status: creating c++/examples/ld/ld_multi_sector/src/Makefile
config.status: creating c++/examples/ld/ld_single_sector/Makefile
config.status: creating c++/examples/ld/ld_single_sector/src/Makefile
config.status: creating c++/examples/lms/Makefile
config.status: creating c++/examples/lms/lms_config/Makefile
config.status: creating c++/examples/lms/lms_config/src/Makefile
config.status: creating c++/examples/lms/lms_mean_values/Makefile
config.status: creating c++/examples/lms/lms_mean_values/src/Makefile
config.status: creating c++/examples/lms/lms_partial_scan/Makefile
config.status: creating c++/examples/lms/lms_partial_scan/src/Makefile
config.status: creating c++/examples/lms/lms_plot_values/Makefile
config.status: creating c++/examples/lms/lms_plot_values/src/Makefile
config.status: creating c++/examples/lms/lms_real_time_indices/Makefile
config.status: creating c++/examples/lms/lms_real_time_indices/src/Makefile
config.status: creating c++/examples/lms/lms_set_variant/Makefile
config.status: creating c++/examples/lms/lms_set_variant/src/Makefile
config.status: creating c++/examples/lms/lms_simple_app/Makefile
config.status: creating c++/examples/lms/lms_simple_app/src/Makefile
config.status: creating c++/examples/lms/lms_stream_range_and_reflect/Makefile
config.status: creating c++/examples/lms/lms_stream_range_and_reflect/src/Makefile
config.status: creating c++/examples/lms/lms_subrange/Makefile
config.status: creating c++/examples/lms/lms_subrange/src/Makefile
config.status: creating c++/drivers/Makefile
config.status: creating c++/drivers/ld/Makefile
config.status: creating c++/drivers/ld/sickld-1.0/Makefile
config.status: creating c++/drivers/lms/Makefile
config.status: creating c++/drivers/lms/sicklms-1.0/Makefile
config.status: creating c++/drivers/base/src/SickConfig.hh
config.status: executing depfiles commands

运行 $make 后，我收到此错误:

me@ MyPC:~/smetiste/Sick/sicktoolbox-1.0.1$ make
Making all in c++
make[1]: Entering directory `/home/me/smetiste/Sick/sicktoolbox-1.0.1/c++'
Making all in drivers
make[2]: Entering directory `/home/me/smetiste/Sick/sicktoolbox-1.0.1/c++/drivers'
Making all in ld
make[3]: Entering directory `/home/me/smetiste/Sick/sicktoolbox-1.0.1/c++/drivers/ld'
Making all in sickld-1.0
make[4]: Entering directory `/home/me/smetiste/Sick/sicktoolbox-1.0.1/c++/drivers/ld/sickld-1.0'
/bin/sh ../../../../libtool --tag=CXX   --mode=compile g++ -DHAVE_CONFIG_H -I. -I../../../../c++/drivers/base/src  -I../../../../c++/drivers/base/src   -g -O2 -MT SickLD.lo -MD -MP -MF .deps/SickLD.Tpo -c -o SickLD.lo SickLD.cc
mkdir .libs
 g++ -DHAVE_CONFIG_H -I. -I../../../../c++/drivers/base/src -I../../../../c++/drivers/base/src -g -O2 -MT SickLD.lo -MD -MP -MF .deps/SickLD.Tpo -c SickLD.cc  -fPIC -DPIC -o .libs/SickLD.o
SickLD.cc: In member function 'void SickToolbox::SickLD::_flushTCPRecvBuffer()':
SickLD.cc:4137:35: warning: ignoring return value of 'ssize_t read(int, void*, size_t)', declared with attribute warn_unused_result [-Wunused-result]
        read(_sick_fd,&null_byte,1);
                                   ^
 g++ -DHAVE_CONFIG_H -I. -I../../../../c++/drivers/base/src -I../../../../c++/drivers/base/src -g -O2 -MT SickLD.lo -MD -MP -MF .deps/SickLD.Tpo -c SickLD.cc -o SickLD.o >/dev/null 2>&1
mv -f .deps/SickLD.Tpo .deps/SickLD.Plo
/bin/sh ../../../../libtool --tag=CXX   --mode=compile g++ -DHAVE_CONFIG_H -I. -I../../../../c++/drivers/base/src  -I../../../../c++/drivers/base/src   -g -O2 -MT SickLDMessage.lo -MD -MP -MF .deps/SickLDMessage.Tpo -c -o SickLDMessage.lo SickLDMessage.cc
 g++ -DHAVE_CONFIG_H -I. -I../../../../c++/drivers/base/src -I../../../../c++/drivers/base/src -g -O2 -MT SickLDMessage.lo -MD -MP -MF .deps/SickLDMessage.Tpo -c SickLDMessage.cc  -fPIC -DPIC -o .libs/SickLDMessage.o
 g++ -DHAVE_CONFIG_H -I. -I../../../../c++/drivers/base/src -I../../../../c++/drivers/base/src -g -O2 -MT SickLDMessage.lo -MD -MP -MF .deps/SickLDMessage.Tpo -c SickLDMessage.cc -o SickLDMessage.o >/dev/null 2>&1
mv -f .deps/SickLDMessage.Tpo .deps/SickLDMessage.Plo
/bin/sh ../../../../libtool --tag=CXX   --mode=compile g++ -DHAVE_CONFIG_H -I. -I../../../../c++/drivers/base/src  -I../../../../c++/drivers/base/src   -g -O2 -MT SickLDBufferMonitor.lo -MD -MP -MF .deps/SickLDBufferMonitor.Tpo -c -o SickLDBufferMonitor.lo SickLDBufferMonitor.cc
 g++ -DHAVE_CONFIG_H -I. -I../../../../c++/drivers/base/src -I../../../../c++/drivers/base/src -g -O2 -MT SickLDBufferMonitor.lo -MD -MP -MF .deps/SickLDBufferMonitor.Tpo -c SickLDBufferMonitor.cc  -fPIC -DPIC -o .libs/SickLDBufferMonitor.o
In file included from SickLDBufferMonitor.hh:24:0,
                 from SickLDBufferMonitor.cc:24:
../../../../c++/drivers/base/src/SickBufferMonitor.hh: In member function 'void SickToolbox::SickBufferMonitor<SICK_MONITOR_CLASS, SICK_MSG_CLASS>::_readBytes(uint8_t*, int, unsigned int) const':
../../../../c++/drivers/base/src/SickBufferMonitor.hh:356:47: error: there are no arguments to 'getdtablesize' that depend on a template parameter, so a declaration of 'getdtablesize' must be available [-fpermissive]
       num_active_files = select(getdtablesize(),&file_desc_set,0,0,(timeout_value > 0) ? &timeout_val : 0);
                                               ^
../../../../c++/drivers/base/src/SickBufferMonitor.hh:356:47: note: (if you use '-fpermissive', G++ will accept your code, but allowing the use of an undeclared name is deprecated)
../../../../c++/drivers/base/src/SickBufferMonitor.hh:370:73: error: there are no arguments to 'read' that depend on a template parameter, so a declaration of 'read' must be available [-fpermissive]
      num_bytes_read = read(_sick_fd,&dest_buffer[total_num_bytes_read],1);
                                                                         ^
../../../../c++/drivers/base/src/SickBufferMonitor.hh: In static member function 'static void* SickToolbox::SickBufferMonitor<SICK_MONITOR_CLASS, SICK_MSG_CLASS>::_bufferMonitorThread(void*)':
../../../../c++/drivers/base/src/SickBufferMonitor.hh:456:18: error: there are no arguments to 'usleep' that depend on a template parameter, so a declaration of 'usleep' must be available [-fpermissive]
       usleep(1000);
                  ^
../../../../c++/drivers/base/src/SickBufferMonitor.hh: In instantiation of 'void SickToolbox::SickBufferMonitor<SICK_MONITOR_CLASS, SICK_MSG_CLASS>::_readBytes(uint8_t*, int, unsigned int) const [with SICK_MONITOR_CLASS = SickToolbox::SickLDBufferMonitor; SICK_MSG_CLASS = SickToolbox::SickLDMessage; uint8_t = unsigned char]':
SickLDBufferMonitor.cc:59:2:   required from here
../../../../c++/drivers/base/src/SickBufferMonitor.hh:356:47: error: 'getdtablesize' was not declared in this scope
       num_active_files = select(getdtablesize(),&file_desc_set,0,0,(timeout_value > 0) ? &timeout_val : 0);
                                               ^
../../../../c++/drivers/base/src/SickBufferMonitor.hh:370:73: error: 'read' was not declared in this scope
      num_bytes_read = read(_sick_fd,&dest_buffer[total_num_bytes_read],1);
                                                                         ^
make[4]: *** [SickLDBufferMonitor.lo] Error 1
make[4]: Leaving directory `/home/me/smetiste/Sick/sicktoolbox-1.0.1/c++/drivers/ld/sickld-1.0'
make[3]: *** [all-recursive] Error 1
make[3]: Leaving directory `/home/me/smetiste/Sick/sicktoolbox-1.0.1/c++/drivers/ld'
make[2]: *** [all-recursive] Error 1
make[2]: Leaving directory `/home/me/smetiste/Sick/sicktoolbox-1.0.1/c++/drivers'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/home/me/smetiste/Sick/sicktoolbox-1.0.1/c++'
make: *** [all-recursive] Error 1
me@ MyPC:~/smetiste/Sick/sicktoolbox-1.0.1$ 

我听说在新版本中使用“旧”包可能会很棘手。但是有没有机会让它发挥作用？

由于它没有任何内部存储器，有没有其他方法可以从 Linux 上的扫描仪获取数据？

Answer 1

该协议(protocol)相对简单且 well documented 。不要被文档的大小吓倒，为了实际使用，您需要一个非常小的子集(从命令 10h,20h 和响应 90h,91h,92h,B0h 开始)。

这是一个可以帮助您入门的小 Python 脚本:

import binascii
import serial
import threading

# =============================================================================

SERIAL_PORT = 'COM6'
# NB: Different crystal, x8 multiplier
SERIAL_BAUDRATE = int(500000 * 14745600 / 16000000 / 8)
SERIAL_TIMEOUT = 1

# =============================================================================

def lms200_crc(data):
  crc16 = 0
  byte = [0,0]
  for c in data:
    byte[1] = byte[0]
    byte[0] = ord(c)

    if (crc16 & 0x8000):
      crc16 = (crc16 & 0x7FFF) << 1
      crc16 ^= 0x8005
    else:
      crc16 = crc16<< 1

    crc16 ^= (byte[1] << 8) | byte[0]

  return crc16

# =============================================================================

class LMS200Telegram(object):
  def __init__(self, data=None):
    if data:
      if len(data) < 7:
        raise RuntimeError("Invalid telegram size")
      if data[0] != '\x02':
        raise RuntimeError("Invalid STX")
      self.address = ord(data[1])
      self.length = ord(data[2]) + (ord(data[3]) * 256)
      self.payload = data[4:-2]
      self.crc = ord(data[-2]) + (ord(data[-1]) * 256)
    else:
      self.address = 0
      self.length = 0
      self.payload = ''
      self.crc = 0

  def generate(self):
    data = '\x02' + chr(self.address)
    self.length = len(self.payload)
    data += chr(self.length & 0xFF)
    data += chr((self.length >> 8) & 0xFF)
    data += self.payload
    self.crc = lms200_crc(data)
    data += chr(self.crc & 0xFF)
    data += chr((self.crc >> 8) & 0xFF)
    return data

class LMS200Command(object):
  def __init__(self, payload):
    if len(payload) < 1:
      raise RuntimeError("Invalid payload size")
    self.opcode = ord(payload[0])
    self.body = payload[1:]

class LMS200Response(object):
  def __init__(self, payload):
    if len(payload) < 2:
      raise RuntimeError("Invalid payload size")
    self.opcode = ord(payload[0])
    self.status = ord(payload[-1])
    self.body = payload[1:-1]

# =============================================================================

def cmd_reset_sensor():
  t = LMS200Telegram()
  t.payload = '\x10'
  return t

def cmd_start_measurement():
  t = LMS200Telegram()
  t.payload = '\x20\x20'
  return t

# =============================================================================

class LMS200Interface(object):
  def __init__(self, port, baudrate, timeout):
    self.port = port
    self.baudrate = baudrate
    self.timeout = timeout
    self.serial = None
    self.serial_rlock = threading.Lock()
    self.serial_wlock = threading.Lock()
    self.buffer = []

  def open_port(self):
    self.serial = serial.Serial(port=self.port
      , baudrate=self.baudrate
      , timeout=self.timeout)

  def close_port(self):
    self.serial.close()
    self.serial = None

  def process_data(self, data):
    self.buffer += data

  def write_telegram(self, t):
    self.serial.flush()
    with self.serial_wlock:
      self.serial.write(t.generate())
    with self.serial_rlock:
      while True:
        ack = self.serial.read(1)
        if len(ack) > 0:
          if ack == '\x06':
            return True
          elif ack == '\x15':
            return False
          else:
            raise RuntimeError("Invalid value received (neither ACK, nor NACK)")

  def worker(self):
    if not self.serial:
      raise RuntimeError("Serial port not initialized.")

    print "Reading serial port '%s'..." % self.port

    while(not self.stop_flag):
      data = self.serial.read(1024)
      if len(data) > 0:
        print "Got %d bytes." % len(data)
        self.process_data(data)

  def run(self):
    lms.open_port()
    self.thread = threading.Thread(target=self.worker)
    self.stop_flag = False
    self.thread.start()

  def stop(self):
    self.stop_flag = True
    self.thread.join()
    lms.close_port()

# =============================================================================

lms = LMS200Interface(SERIAL_PORT, SERIAL_BAUDRATE, SERIAL_TIMEOUT)

lms.run()

您仍然需要将 process_data 方法扩展为:

检测并分离各个电报帧。

最简单的方法是查找 STX 字节的出现。地址字节通常是恒定的，因此您实际上可以搜索例如0x02 0x80 。您还可以对长度进行一些验证。然后尝试读取有效负载，并查看 CRC 是否匹配。

识别电报时，需要解析payload。

通过命令/响应字节识别有效负载类型。

使用 Python struct 模块解释有效负载。

根据需要处理测量数据。确切的形式将取决于测量模式。例如，在基本测量模式下，您将拥有一个以 mm 为单位的 361 个 16 位距离数组，以 0.5 度为步长。您需要屏蔽存储在最高有效位中的标志，并处理表示错误条件的特殊值。

我没有在脚本中实现这一点，因为它只是为了在我们的串行卡出现兼容性问题时进行一些基本的通信测试而编写的。