FAQ

VI Sensor is not detected

• If you have problems detecting the sensor, connect the sensor directly to your PCs ethernet port and do a power cycle. It is important that your ethernet port is configured to be operated in DHCP mode where you automatically receive an IP. A few seconds after booting up your sensor, you should get an IP from the sensor, namely 10.0.0.5 . If not, try running:

sudo dhclient eth0

assuming that eth0 is the network interface of your ethernet adapter.

• If, when you connect directly to the sensor, your PC gets an IP (10.0.0.5), you can ping the sensor (10.0.0.1), but autodiscovery can not find the sensor, try the following steps: ssh on the sensor, remount the sensor filesystem as writeable, remove the fpga/FPGA_BITSTREAM_BROKEN file and reboot the sensor.

ssh root@10.0.0.1
mount -o remount,rw /
rm fpga/FPGA_BITSTREAM_BROKEN
reboot && exit

This can happen due to unstable power at boot-up, which can get the embedded software locked. The symptom would be that your FPGA LEDs continue to blink alternating while booting instead of having only one blinking LED when the sensor is ready.

• If you still do not get an IP, please contact our support support@skybotix.com

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Firmware version not compatible

Please make sure that you've successfully...

1. updated the sensor according to the visensor_tools readme: https://github.com/skybotix/visensor_tools

2. Pull the newest version of libvisensor: https://github.com/ethz-asl/libvisensor

3. Pull and build the newest version of the visensor_node: https://github.com/ethz-asl/visensor_node

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How to set a static IP address to the Skybotix VI Sensor

Map a static IP to your sensor using its MAC address. This is done in the DHCP settings of your router. For getting the MAC address of the sensor you can ssh to the sensor and run ifconfig.

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Connecting to a specific sensor IP

If you use the ROS visensor_node, use the option to either define the sensorIp or sensorId parameter as described here.

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How to ssh to the sensor

Assuming that the sensor IP is 10.0.0.1, you can ssh to the sensor with

ssh root@10.0.0.1

No password is required. Be aware that due to tampering with the sensor over ssh the sensor might become unusable. Thus it is advised that only experienced users use the sensor in this way. Skybotix explicitly takes no responsibility for any problems related to manipulating the sensor over ssh.

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Orientation from imu0 message

The ADIS IMU provides angular rates, accelerations, magnetic field and pressure. However, there is no attitude estimator included. We are currently working on a complementary filter that will fuse the inertial data in order to obtain an attitude estimate.

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Using visual odometry and the IMU

Currently, our customers use KF frameworks such as msf https://github.com/ethz-asl/ethzasl_msf to fuse the odometry output with the IMU. We are currently working on a tightly coupled visual-inertial odometry solution that we want to make available to our customers.

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Noisy disparity output

Two issues can lead to very noisy disparity output of the standard ROS stereo pipeline as described here.

• The visensor_calibration_flasher from the visensor_tools overwrites the onboard factory calibration. Contact support@skybotix.com to get the original calibration file and revert the factory calibration.
• Recalibration of the sensor is required if the positioning of the Lenses, the imager chips or the IMU has changed (e.g. due to hard impacts). Have a look at the Sensor Calibration section for more information on sensor recalibration.

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Further Questions?

Please contact our support support@skybotix.com

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