Posts made by Alex Kushleyev

@Michael-Soul , it is EAR99

@restore , a few more things:

• you should set the auto exposure to lme_msv, which is the non-isp option, since we would not be using isp in this case
• before saving the raw bayer, start the misp output stream, so that AE can actually process, otherwise the exposure will be stuck in default value -- the bayer stream does not trigger AE to process.

Alex

@restore, that is strange. Does this effect appear in the jpeg snapshot only? (as opposed to the preview stream).

Yes, we do support saving raw bayer10 for this camera. For 9248 x 6944, each image would be something like 80MB (10-bit bayer)

In order to test it,

• set your preview width and height to 9248 x 6944
• en_raw_preview : true
• en_snapshot : false (for now)
• en_misp : true
• set misp width and height to something reasonable (1920x1080)

When you run it, assuming there are no errors, you should see hires_bayer pipe and you can dump individual images using voxl-record-raw-image tool.

I have not tested this in a while, but it should work. Let me know if you run into any issues.

Also, please use an SDK that is not older than few months, as we recently enabled the full raw resolution support for this camera.

Regarding the jpeg smoothing, the parameters are baked into the chromatix tuning file and we have not tuned that for any particular application. However, you should first check whether the jpeg encode quality is sufficiently high. snapshot_jpeg_quality param in your voxl-camera-server.conf is set to 75.

Alex

@austin-c , The GPS driver is built for SLPI as well as APPS PROC, so you could connect it to a apps-proc UART and start the driver on the apps proc side of PX4.

This was done on RB5 : https://docs.modalai.com/Qualcomm-Flight-RB5-linux-user-guide/

https://docs.modalai.com/voxl2-linux-user-guide/

Regarding magnetometer, just like with the GPS driver, you should be able to enable the mag driver to build for apps proc. Since the apps proc i2c uses standard posix interface, it should just work. However, i don't think we have ever tried it.

Alex

@ktrieu , you can find the STEP file for the M0166 camera module here : https://docs.modalai.com/pcb-catalog/

@syamala-kotireddy ,

If your M0129 ESC only has a label that says M0129, it most likely means it is M012-3. The only difference between -3 and -6 is that -6 is rated for 6S battery voltage (which is irrelevant for Starling 2).

Was the ESC working? How did it get into non-working state?

Please make sure PX4 is not running before you use the voxl-esc tools : systemctl stop voxl-px4. You should reboot, disable voxl-px4 and try to use voxl-esc tools directly from /usr/share/modalai/voxl-esc/

In order to test if the ESC itself is working, the best way to connect it directly to a Linux PC using a serial-to-usb adapter and use voxl-esc to scan, test, etc. You can make your own adapter or purchase one here.

Also, double check if the status of ESC LEDs when you turn on the power. Additionally, does the ESC make motor sounds? See additional debugging information here : https://docs.modalai.com/voxl-escs/faq/

Alex

@Jskim , you should check dmesg to see maybe there are some warnings. Perhaps the device is not de-initialized properly (how are you powering it off?) and next time the OS allocates a new Device ID.

Either way, using udev rule should help resolve the issue, however make sure there is no resource leak as a result of the device on/off. Also, if you keep turning the device on/off, does the device ID increment indefinitely?

Alex

@fhaltmayer , unfortunately, we do not have any updates at this time. It looks like we may never release Ubuntu 20.04 for VOXL2 because it is a LOT of work to switch to a new major Ubuntu release and test + maintain everything. Additionally, even Ubuntu 20.04 is already relatively old, so we are trying to focus our efforts on more forward-looking software development with larger impact.

Alex

Hi @austin-c ,

You can find the latest M0138 firmware with regen completely disabled here

Also, I added the esc config that i've been using for testing here

For step tests, i have been using pretty aggressive step command:

./voxl-esc-spin-step.py --id 2 --rpm 2000 --step-amplitude 4000 --step-frequency 2.0 --timeout 2.0 --cmd-rate 2000 --enable-plot 1

In order to make the ESC not de-sync (due to long demag time of the motor), the following params were adjusted:

• max_rpm_delta set to 4000 (you can go lower), to cap the maximum rpm transitions. Although in my test, the step is 4000, so this had no effect
• timing_advance: 45 -- this is pretty high commutation advance to trigger commutation earlier so that there is more time for back-emf sensing -- high advance wiil reduce motor efficiency and will cause the motor to heat up a bit more
• sense_advance: 30 -- delay back-emf sensing so that we don't sample back-emf during the motor coil demagnetization
• more details : https://gitlab.com/voxl-public/voxl-sdk/utilities/voxl-esc/-/blob/dev/voxl-esc-tools/doc/low_kv_motor_tuning.md

I had another thought.. What if you use a small battery to absorb the voltage spikes? Basically hook up a 6-7S battery with a beefy Schottyky diode (10A) set up with Cathode (negative) pointing to the battery.

• you will have to make sure the power supply voltage never exceeds battery voltage + diode drop.
• you will also need to make sure that you don't over-charge the battery with repeated spike absorption.. It is possible to have some sort of self-discharge circuit to slowly discharge the battery to a certain voltage (using a Zener diode + resistor or something similar).

Anyway, just an idea..

Try out the no-regen firmware..

Alex

@fhaltmayer , it looks like there maybe something missing from /usr/lib/camera/, as the camera is detected by the i2c probe but not accepted by the system.

Can you please let me know how exactly the camera is connected (to camera slot/id 2, it seems) and also list all the contents of /usr/lib/camera/.

Alex

@cbay , yes this should work.

Whenever you add cameras of the same type, you should always check for possible I2C (CCI) conflicts. If you look here https://docs.modalai.com/M0188/#image-sensor-interfaces , the sensor IDs 0,2,3,6 (which is what you use) use unique CCI buses 0-3, so that is all good.

If you used ID 1, it would conflict with with another AR0144 on ID6 (both use CCI1)

One last thing to check is the sensor sync.

• if you see fsin in the configuration of the sensor (and name of the sensormodule in /usr/lib/camera/), it means it is set up as a sync slave
• currently you have the IDs 0 and 6 set up as sync slaves, but ID 2 and 3 as free-running

There are two issues enabling sync'ed drivers for AR0144 in ID 2 and 3:

• the driver is provided only for ID2 in : /usr/share/modalai/chi-cdk/ar0144-fsin/ - this is easy to fix
• ID1 and ID3 on M0188 do not have the sync line connected to the camera connector
  • this is easy to fix by installing a 0-ohm resistor, which is DNI by default.

Depending on your requirements for VIO (which VIO are you using?), you may or may not need the cameras synchronized.

Please let me know your requirements and we can go from there..

Alex

Hello @adam , please see the following post regarding GPS signal quality on Starling 2 and Starling 2 Max : https://forum.modalai.com/topic/5116/gnss-emi-mitigation-guidelines

There is no voxl-gps service - voxl-px4 handles the GPS functionality, so as long as that is running, the GPS module should be active. Please go through the documentation linked above, there are some mitigation steps that are relatively easy to implement.

We apologize for the inconvenience, but enabling usable GPS on Starling 2 will require some tweaks.

Alex

@RyanH ,

Sometimes there is small pieces of random magnetic debris that gets stuck in the motor.

First, you could try using compressed air to clear out the motor.

Additionally, It could help to spin the motor up and down using voxl-esc command line tools a few times to clear it out (without prop is best, just for safety). Spinning the motor without prop a bunch of times could get the debris dislodged and actually broken up by the moving motor parts, so that the debris is no longer large enough to cause a problem. Reversing motor spin using voxl-esc test tools can help dislodge the debris (you can commend negative power/rpm).

You can find useful info regarding motor testing here : https://docs.modalai.com/voxl-escs/faq/

Alex

@groupo , thank you for the feedback and offer to help. Yes, please send us an email with some more details and we can discuss if there is an opportunity to collaborate.

Alex

@Roy-Azriel , the description of Starling 2 Max states that it uses VOXL2, as well as lists other major components and options for camera configurations : https://www.modalai.com/products/starling-2-max?variant=48216084087088

Please let us know what Lidar you are considering adding.

Alex

@aheyne , please send us a message via contact form. We don't sell this part separately as a product, but will help you with a replacement.

You will need the M0177 flex cable (as the print states on the cable).

https://www.modalai.com/pages/contact-us

Alex

@Piyush-Singh , can you please provide more details

• how exactly all cameras are connected to VOXL2 mini (including interposers, flexes), etc. A diagram would help a lot
• which kernel variant are you running on your voxl2 mini (2.0.0 or 2.0.2).

Are all the other cameras working if you disable the TOF sensor in the camera server config?

Alex

@Shantanu-Gupta please check documentation and video for VOXL2:

• https://docs.modalai.com/voxl2-voxl2-mini-system-image/#force-voxl-2-into-fastboot
• https://docs.modalai.com/voxl2-connectors/#buttons
• https://www.youtube.com/watch?v=IM3PnW7cipQ

Alex

@fhaltmayer , which wifi usb adapter are you using?

Hello @RoyAzriel ,

If you are going to be experimenting with adding different sensors (Lidar), then Starling 2 Max is definitely going to offer more flexibility due to the larger size and longer flight time.

You should consider the dimensions of the tunnel and make sure that the drone will easily fit. I have no idea how small the cross section of the tunnel is, but if it is very small (just several times larger than the diameter of the drone), then it would be very difficult to fly due to air circulating in a small space.

What Lidar are you considering adding and what is its weight and communication interface?

The illumination will depend on your specific application, depending on how far you need to see. You should be able to add standard LED lights. if you need to control the LED intensity, you would need to get an LED with built in adjustable LED driver and optionally control it using PWM output feature on the ESC.

Are you going to develop your own mapping and navigation stack for this application?

Alex