Applanix alternative

Hello Marcel,

Thanks for taking the time to read and learn about the OpenMMS project. The current OpenMMS hardware (v1.3) only supports using the Applanix APX-18 GNSS-INS sensor. By supports, means that the OpenMMS documentation describes (in great detail) how the aluminum case and printed circuit boards need to be manufactured to physically integrate the APX-18 sensor into the OpenMMS hardware, and how the post-processing software workflows utilize the collected GNSS-INS data from the sensor (requiring the use of the Applanix POSPac UAV software).

For your reference, the latest pricing information I have for a single APX-18 sensor is (subject to change, contact Applanix directly for up-to-date pricing):

– APX-18 Sensor [Quantity 1]: $19,750 USD
– Trimble AV14 GNSS Antenna [Quantity 2]: $990 USD
– POSPac UAV Software (12 month maintenance) [Quantity 1]: $862 USD

For a total of $21,602 USD which accounts for 80% of the total OpenMMS hardware cost if using a Velodyne VLP-16 lidar sensor ($3,999 USD), or 91% of the total OpenMMS hardware cost if using a Livox MID-40 lidar sensor ($599 USD).

One of the long term goals of the project, is to, “entice sensor manufacturers to want their products to be integrated into the OpenMMS project, thus providing different accuracy and cost options for users and, in turn, new customers for the manufacturers”. However, no other GNSS-INS sensor manufacturers have yet expressed interest in having their sensor(s) integrated into the project. Of course any GNSS-INS sensor with appropriate size and weight characteristics can, in theory, be integrated into the OpenMMS project, but would likely require modifications to the case design and printed circuit board designs.

Stay safe!

-RGB

• This reply was modified 4 years ago by Ryan B.
• This reply was modified 4 years ago by Ryan B.

Hi,

I too was gob smacked by the price of the gnss/imu. I love this project, but it just isn’t viable due to the prohibitive cost.

I understand the idea to encourage the manufacturers to reduce their prices, but it seems to me that maybe a better approach is to use a cheap alternative to encourage them to do this. Why would anyone pay $19,000!!? For a gps and imu that can be bought for a few dollars in off the shelf parts?

Surely the whole point of and open source system is one that is affordable? The rest of the system looks great, especially the livox mid range, raspberry pi – all that is required is a cheap imu and gps chip.

I hope you might consider developing another version using affordable parts.

Thanks for the amazing work all the same!!

Best regards, Andrew.

Yes, the price of the IMU/GNSS is large and it is the main problem with this project. However some things have to be clear – this project provides step by step hardware and software integration guide with a total cost of cca 22 000€ for an advanced UAV LiDAR system that typically costs 2-3 times more in retail, despite being built with the same components.
And another thing is that most of UAV LiDAR manufacturers still do not have their firmware sorted out and have all kinds of issues with reliability – what I am trying to say is that they are not plug and play and there is almost no any special benefit from using the commercial solution.

From that point of view, this project is extremely valuable for anybody that wants to save a lot of money.

I do not think that the point of the open project is to have an affordable system – in my opinion, the goal of the open project is to have a free solution that can go toe to toe with commercial solutions (for example the ardupilot project) and this is exactly what this project offers.
However the path towards this end-goal typically has smaller steps, and along the way community is built.

The price for building the UAV LiDAR system will never be cheap i.e. it will always be more than a few thousand euros. Livox recently changed the game when introducing the low-cost LiDAR+IMU sensors and it will surely make this project more appealing to everyone. Ublox has developed F9 dual-frequency GNSS receiver (cca 200 USD), and it just sits there and waits to be used in this project. This would decrease the cost of the project drastically!
Ryan told me that he plans to focus on Livox sensors and make use of built-in IMU, which will be great for attracting more people to participate in the project.

Also, the Sparkfun GNSS RTK chips provide a +/- 2cm (allegedly) RTK base station for just a few $100 –

IMU chips are pennies, whilst these may not be top of the range solutions, it does make an entire setup under $1000, which for me and I’m sure hundreds of others, is affordable.

Anyway, I’m not complaining in any way – I think this project is amazing, the level of detail and dedication to it is truly impressive, thanks guys!

Hi woody!
Yes, that is true, it is also based on ublox F9 chip. Imu chips are pennies, but it is really the crucial part if we are talking about accuracy or application of built LiDAR system. Those that would give good results cost more than a penny, they are very expensive actually. I am not even sure that the one that Livox has built-in (bosch BMI088) is sufficient for reasonable flying height (e.g. 50-60m) with reasonable product accuracy. Nevertheless, I think it would be nice to have that option to use cheap IMU. Another issue is the software – typically you get the software along with the IMU/GNSS if you buy Applanix or OxTS NAV650/250 you get a processing software. A large piece of the price tag surely goes for the software. I think that they give tightly coupled GNSS/IMU solution, which is not trivial and I don’t think there is open-source software for that at the moment.

But you got to start somewhere 🙂

I agree with you, this amount of work, dedication and attention to the detail is insane!

Hi Lukaj,

I completely get it, and do agree – you get what you pay for!

I just think it would be more inclusive and would encourage more people, (especially young enthusiasts (the future of dev)) to have a go at the project if it was affordable (irrespective of sub-cm accuracy (bearing in mind the Livox mid range only has <2cm accuracy anyway)), whereas with the pro GNSS/IMU setups, it’s just limiting it to very very few people who would have the time and money to invest in it making it not so “open” source. And actually, makes it not much cheaper than just buying a finished off the shelf solution anyway.

RE the software, I can see is a draw back, but there are quite a few ready built packages for ROS out there (including one provided by Livox) that are an extremely good starting point to build in individual components. And once that can be sorted, with a larger number of interested open source users of this project, due to the lower cost, that would get developed in no time. That is one of the benefits of an open source project, the power of open source development. Keeping the project at a very high cost price excludes any external minds to develop it.

I think it would be good to have two branches, one (that is already done) for a top of the line solution, and a second affordable albeit slightly less accurate version.

Hi woody!

I agree with what you said and having more branches is a good solution to satisfy people with different interests. Ability to build something using low-cost equipment is basically mandatory for open source projects.

I would like to see what Ryan thinks about the future of the project and which way somebody can get involved!

Hi Luka and Andrew,

Thanks for adding to the discussion on an Applanix alternative GNSS-INS sensor for OpenMMS. Luka, you stated, “the goal of the open project is to have a free solution that can go toe to toe with commercial solutions”, and you are 100% correct! Practically all of the commercial UAS-Lidar solutions utilize commercial off-the-shelf (COTS) sensors within their imagery and/or lidar-based mobile mapping systems. OpenMMS takes the exact same approach, grab a bunch of commercially available sensors, and integrate them to produce a mobile mapping system. However, OpenMMS attempts to do so with complete transparency, and in such a way that interested users can potentially add their own ideas to the baseline implementation. Hopefully I’m right!?! I am in the process of investigating alternative GNSS-INS sensors to replace the Applanix APX-18 sensor currently being used. Luka, I just posted a somewhat detailed ‘future of OpenMMS’ response to your General Discussion Forum question, you can read the response here.

Understandably, when the concept of mapping is discussed, most often X,Y,Z coordinates are the first thing that comes to mind. It has become common knowledge that if accurate and precise X,Y,Z coordinates are required, RTK GNSS is the solution, which is not wrong. However, when it comes to lidar-based mobile mapping systems (i.e., dynamically moving mapping systems) having the accurate and precise X,Y,Z coordinates of your mapping sensor(s) during a data collection mission is only one half of the problem. The other half is having accurate and precise orientation (aka. attitude) values for your mapping sensor(s), and of course the solution to this is an IMU. Because the lidar sensor is observing features of interest that are some distance away from itself, it is the combination of the lidar sensor’s X,Y,Z coordinates, the orientation (i.e., direction) of the observing laser, and the measured distance to the feature that all factor into the accuracy and precision of the X,Y,Z coordinates calculated for the mapped feature. As lidar observations increase in distance, the more impact the orientation values have on the feature’s calculated coordinates. Hence, using reasonable quality IMU sensors is important. I hope this helps to better explain the roles of the GNSS and IMU sensors from the perspective of mobile mapping. Please let me know if you (or anyone else reading this) have any questions.

Thanks again,

-Ryan

• This reply was modified 3 years, 10 months ago by Ryan B.

Hi,
OpenMMS the first complet open source project i found in internet, great work and documentation !!

For this GNSS-INS hardware, a new Aceinna OpenRTK330 borad is a good example te reduce coast of this amazing project
https://www.aceinna.com/inertial-systems/OpenRTK330

best regards

Wouldn’t something like below make more sense? Only about USD500 but pretty similar to applanix.
Specs wise , you think this would work?

https://item.taobao.com/item.htm?ut_sk=1.WoQX2CGUZeUDAGvMuSdaKCKM_21380790_1608780419990.Copy.1&id=632416253984&sourceType=item&price=2999-3500&suid=EF0988AE-E6C1-4871-86F2-C34A0DFCC8A7&shareUniqueId=6565420047&un=0fc80cb90ebb2784defba349c3f14615&share_crt_v=1&spm=a2159r.13376460.0.0&sp_tk=amZZQ2NKdXd5VHA=&cpp=1&shareurl=true&short_name=h.4TOpkZB&bxsign=scdC7zEaEwhKwW-4e02gA6TEg9UR3lwNktGhIB4-B-dv78F9Y9MKlmBuQ26m2YM9om7-MtOfr1zIFfH6ySBmSOm_nuAfe4Tb4j1pI2Yyh56BhQ&sm=2f33db&app=chrome

Aside from the physical fitting of this, could this technically work?

https://navio2.emlid.com/

Fitting aside, might this work?

https://navio2.emlid.com/

Also, the Sparkfun GNSS RTK chips provide a +/- 1cm (allegedly) RTK base station for just a few $100 – https://www.sparkfun.com/products/17369

IMU chips are pennies, whilst these may not be top of the range solutions, it does make an entire setup under $1000, which for me and I’m sure hundreds of others, is affordable.

Anyway, I’m not complaining in any way – I think this project is amazing, the level of detail and dedication to it is truly impressive, thanks guys!

Guys I am a new member here who have just purchased a Mid-40

I did it after finding OPENMMS but I did not realise APX-18 costs so much. Can somebody answer a few questions related to OPENMMS hardware and a specific application.

As I understand a Mid-40 comes with Windows software(Luvox Viewer) that will allow to see point cloud in real time through a wired connection. Is there is any app IOS/Android that can do the same including saving point cloud data in a file wirelessly? Something like through a Bluetooth dongle that support Serial communication over Bluetooth.

At this point I do not need an airborne LiDar and I am planning to use the Mid-40 for scanning from a ground. It can be anything outdoor or indoor. Do I really need APX-18 for it? What functionality it provides if I just want to walk with Mid-40 or drive a rover with it?

I do have Polaris Alpha RTK which is really cheap to buy but they come with licenses to pay both for rover/base to use them in RTK mode. A license is not that expensive and you can buy one for $200 per rover/base. It is designed to use as a standalone RTK or can be hooked up to Arduino. If there is no license you can just use one receiver with two GNSS constellation and it gives 30cm accuracy.

As for accuracy of 3D data captured I do not actually need any great accuracy. I want a system to bring real environments in 3D into Blender for games and CGI virtual tours so I am happy with even 5-10% error in 3D data as long as I get al details I need.

To be honest I wouldn’t even look at OPENMMS at this point but what bugs me that the MID-40 will just capture 3D data without any colour information and I would prefer to get colorized point cloud.

If anybody knows any other solution that can help me to add all real textures to the captured point cloud I would really appreciate it.