Cepton Sora 200 User manual

SORA 200
User Guide

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Table of Contents
Table of Contents
Revision History
Warnings
Specifications
Getting Started
CeptonViewer
Data Exporter
Configuration
SDK
ROS
Accessories
Troubleshooting
Cables
Drawings
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Revision History
Date Version Description
14 Nov 2017 1.0 Initial Release
© 2017-2018 Cepton Technologies, Inc. All rights reserved.
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Warnings
The sensor is Class 1 eye safe.
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Specifications
Performance
Angular Resolution (H x V) 0.2°
Data Rate (points per second) 102400
Detection Range 1m - 200m
FOV 60° x 18°
Frame Rate 200Hz
Lines (H x V) 300 x 2
Output 100 Mbps Ethernet, UDP Packet
PPS/NMEA Yes
Range Resolution 2.5cm
Mechanical
Dimensions (W x D x H) 8.9cm x 6.6cm x 10cm
Weight 550g
Electrical
Input Power 12W
Input Voltage 12V DC
Laser Wavelength 906nm
Environmental
Environmental Protection IP67
Ambient Vibration 2G
Ambient Operating Temperature -20°C to 65°C
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Aerial Mapping
Given a SORA sensor mounted vertically on an aerial platform, moving perpendicular to the scanline
direction, the following equations estimate mapping point density:
height [m]: sensor height above ground
speed [m / s]: speed perpendicular to scanline direction
sweep [m]: ground sweep distance along scanline direction
density [points / m^2]: points per ground area
sweep = ± 0.58 ∗ height
density =
1e4
height ∗speed
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Getting Started
Website: http://www.cepton.com/
Developers: https://github.com/ceptontech/
Mounting the Sensor
The sensor vibrates during normal operation. If not properly mechanically isolated, it can cause
excessive audible noise or interference to other sensors that are sensitive to vibration. We
recommend mounting the sensor using vibration isolating rubber or foam. If using the sensor on a
tripod, ensure that the tripod is rigid and does not vibrate excessively when the sensor is powered on.
Connecting the Sensor
Connect the sensor's power cable (barrel plug) to the provided 12V power supply. Connect the
sensor's Ethernet cable to the host computer (we recommend using a USB -> Ethernet adapter).
The sensor IP address is of the form 192.168.*.* , and it sends UDP broadcast packets on port
8808 . The sensor will start sending packets as soon as the power is connected.
On Ubuntu, it is necessary to assign a static IP address to the host computer's Ethernet interface (e.g.
IP= 19.168.0.2 , Netmask= 255.255.0.0 ). This can be done through the NetworkManager GUI.
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Visualizing the Data
To start, download and run CeptonViewer. The sensor should appear immediately in the viewer. If it
doesn't, refer to Troubleshooting.
Capture
The Cepton tools support loading PCAP network capture files for reviewing sensor data offline. A
PCAP file can be saved using CeptonViewer, Wireshark, tcpdump, or any other network capture tool.
The PCAPNG file format is not supported.
To capture network traffic using tcpdump, run the following:
sudo tcpdump -i NETWORK_INTERFACE port 8808 -w OUTPUT.pcap
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CeptonViewer
Downloads
CeptonViewer can be downloaded from our SDK repository:
https://github.com/ceptontech/cepton_sdk_redist.
Windows x64: cepton_sdk_redist/bin/win64/CeptonViewer.exe
Linux x64: cepton_sdk_redist/bin/linux-x86_64/CeptonViewer
Mac: cepton_sdk_redist/bin/osx/CeptonViewer
ARM x64: cepton_sdk_redist/bin/linux-aarch64/CeptonViewer
Getting Started
On Windows, a firewall popup will appear the first time CeptonViewer is launched. Select "Allow
access" for both private and public networks.
The main menu is located on the left side of the screen. Select Help to bring up a basic help menu.
Select Reset to reset the viewer. The visualization settings can be found in the Viewer sub
menu.
Capture
A PCAP network capture file can be saved in the viewer by clicking Capture -> Start Capture ,
then Capture -> Stop Capture when done. The capture file can then be loaded by clicking
Capture -> Load Capture or by dragging and dropping the capture file into the viewer.
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Transforms
CeptonViewer has support for viewing multiple sensors either individually or combined. To view the
sensors combined, the sensor transforms must be specified. First, to enable transforms, ensure that
Show Advanced and Transforms -> Enable are both selected. The transforms can then be
either inputed directly in the viewer or loaded from a JSON file.
Viewer
To edit coordinate transforms in the viewer:
1. Open up the individual sensor menu at the bottom of the main menu. Select the Transform sub
menu, and edit the sensor's transform.
2. To save the transform to a JSON file, click Transforms -> File -> Save As... .
JSON
A JSON file can be loaded by clicking Transforms -> File -> Load .
Template:
{
"sensor_serial_number": {
"rotation": [x, y, z, w],
"translation": [x, y, z]
}
}
Sample:
{
"1": {
"rotation": [
-0.01264648623717563,
-0.0012783561222154416,
1.6168019276402304e-05,
0.9999192127017427
],
"translation": [
0.0,
0.0,
2.1087962181388047
]
}
}
Controls
GUI
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Command Key
Help F1
Hide GUI F11
Replay
Command Key
Pause/Resume SPACE
View
Command Mouse Keyboard + Mouse Keyboard
Rotate View LButton Arrow Keys
Translate View MButton Control + LButton Control + Arrow Keys
Zoom View RButton Shift + LButton Shift + Arrow Keys
Command Key
Reset View Origin O
Front View 1
Top View 2
Side View 3
Mirror M
Flip F
Perspective P
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Data Exporter
Downloads
The data exporter can be downloaded from our SDK repository:
https://github.com/ceptontech/cepton_sdk_redist.
Windows x64: cepton_sdk_redist/bin/win64/data_exporter.exe
Linux x64: cepton_sdk_redist/bin/linux-x86_64/data_exporter
Mac: cepton_sdk_redist/bin/osx/data_exporter
ARM64: cepton_sdk_redist/bin/linux-aarch64/data_exporter
Usage
USAGE
data_exporter [OPTIONS] OUTPUT_FILE
DESCRIPTION
Exports Cepton LIDAR data to a file.
FORMATS
`csv`
CSV file format.
`bin`
Binary file format. Array of `CeptonSensorPoint` structs.
OPTIONS
-c CAPTURE_FILE
Load data from capture file.
-n N_FRAMES
Number of frames to capture. Default is 1.
-f FORMAT
Default is 'csv'.
--split
Create multiple output files with single frame per file.
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Configuration
Serial Tool
The following sensor parameters can be configured:
Destination IP address (default: 255.255.255.255 )
Destination MAC address (default: ff:ff:ff:ff:ff:ff )
Destination port (default: 8808 )
Sensor IP address
Download the serial tool: http://cepton.com/downloads/cepton_serial_redist.py.
Install Python dependencies.
$ pip install ipaddress pyserial
Connect the sensor's serial cable to the host computer using a serial -> USB cable. Connect the
sensor's power supply.
List the serial ports.
$ python cepton_serial_redist.py --list_ports
Run the serial tool.
$ python cepton_serial_redist.py --port PORT --serial SENSOR_SERIAL_NUMBER \
[OPTIONS]
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SDK
Getting Started
Installation
Clone the Cepton SDK.
$ git clone --recursive [e-mail]:ceptontech/cepton_sdk_redist.git
$ cd cepton_sdk_redist
Windows
$ mkdir build
$ cd build
$ cmake -G "Visual Studio 14 Win64" ..
$ start "cepton_sdk_redist.sln"
Unix
$ mkdir build
$ cd build
$ cmake ..
$ make
Basic Interaction
Initialization
To start interacting with the Cepton SDK, call cepton_sdk_initialize with an on_event
callback.
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#include <cepton_sdk.h>
void on_event(int error_code, CeptonSensorHandle sensor,
struct CeptonSensorInformation const *p_info, int event)
{
if (error_code < 0) {
// Handle error
return;
}
switch(event) {
case CEPTON_EVENT_ATTACH:
// Handle new sensor
break;
case CEPTON_EVENT_FRAME:
// Handle new frame
break;
}
}
int main(int argc, char ** argv) {
cepton_sdk_initialize(CEPTON_SDK_VERSION, 0, on_event);
// Main code
cepton_sdk_deinitialize();
return 0;
}
Reference
Data
Timestamps
If your sensor has a GPS module connected, point timestamps will be based on the GPS clock,
otherwise they will be based on the host computer's clock.
Intensities
Intensity values are in the range [0.0, 1.0] . Intensity values default to 1.0 if unsupported by the
sensor/firmware.
Image Points
Image points are in camera image coordinates with a focal length of 1.0 . Sample code for
converting to 3D points can be found at samples/basic_interaction/point.hpp.
Notes
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Multiple returns
To use multiple returns feature, the SDK needs to be initialized with
CEPTON_SDK_CONTROL_ENABLED_MULTIPLE_RETURNS control flag set.
Currently Cepton sensors only support up to 2 returns.
First return is always the strongest signal.
Second return is the last detectable signal if it is not the strongest. Otherwise it is the second
strongest signal detectable.
Second return can be empty if only one signal is detectable.
Some applications require the farthest return. Farthest detectable signal is guaranteed to be
always present in the list, compare the distance of the two returns to obtain it reliably.
Threading
Callbacks are invoked from a networking thread that is launched by cepton_sdk_initialize .
Callbacks should be short to avoid dropped packets. If you need more than ~1ms to handle a
callback, then the data should be handled asynchronously in another thread (e.g. through a
queue).
Callbacks are not re-entrant since they come from a single thread.
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ROS
Getting Started
First, read the main Getting Started guide.
Installation
If you have not done so already, install ROS, and create a catkin workspace.
Change to the catkin workspace directory.
Clone the Cepton ROS driver.
$ git clone --recursive [e-mail]:ceptontech/cepton_ros.git src/cepton_ros
Run catkin make.
$ catkin_make
Source the catkin setup script.
$ source devel/setup.bash
Running the demo
Ensure that the sensor is powered on and connected to the host computer.
Launch roscore .
$ roscore
In a separate terminal, launch demo_single.launch .
$ roslaunch cepton_ros demo_single.launch
A rviz window should popup showing the sensor point cloud.
Driver
To view the driver arguments pass the --ros-args option.
$ roslaunch --ros-args cepton_ros driver_single.launch
Using multiple sensors
Create a transforms JSON file (see Transforms). Launch the driver_multi.launch file.
$ roslaunch cepton_ros driver_multi.launch transforms_path:=TRANSFORMS.json
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The driver will publish separate topics and transforms for each sensor. You must manually launch
rviz, and add the point clouds.
$ rosrun rviz rviz
Troubleshooting
First, try viewing the sensor in CeptonViewer to determine if the issue is related to ROS or the
sensor/network. Also, read through the main Troubleshooting guide. If it is a ROS issue, contact
Cepton for support.
Reference
Driver Nodelet
The driver nodelet is a thin wrapper around the Cepton SDK. It publishes sensor messages and
PointCloud2 topics for each sensor. The point type definitions can be found in
include/cepton_ros/point.hpp.
cepton_ros::CeptonImagePoint
timestamp (uint64)
image_x , image_z (float)
distance (float)
intensity (float)
cepton_ros::CeptonPoint
timestamp (uint64)
x, y, z (float)
intensity (float)
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Accessories
Interface Box
Interface box front.
Interface box back.
Specifications
Dimensions (W x H x D) 17cm x 11.5cm x 5.5cm
Getting Started
Connect the sensor serial cables to the serial ports on the front of the interface box. Connect the
sensor Ethernet cables to the Ethernet ports on the front of the interface box.
Connect the GPS serial cable to the serial port on the back of the interface box.
Connect the supplied power supply to the power port on the back of the interface box.
Connect the host computer's Ethernet to an Ethernet port on the front of the interface box.
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