Marvelmind Indoor Navigation System User manual

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Marvelmind Indoor Navigation System
Operating Manual
V2017_05_20
www.marvelmind.com

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Table of contents
1. Version changes ...................................................................................................................................................... 3
2. Executive summary ................................................................................................................................................. 4
3. Basics of the system ............................................................................................................................................... 6
3.1 What’s in the box .............................................................................................................................................. 6
3.2 Indoor GPS architecture .................................................................................................................................... 7
3.3 Indoor “GPS” syste – close-up and internal view ........................................................................................... 8
3.4 Syste ele ents ............................................................................................................................................... 9
3.4.1 Stationary beacons ....................................................................................................................................... 9
3.4.2 Mobile beacon (“hedgehog”) ..................................................................................................................... 10
3.4.3 Mode /router ............................................................................................................................................ 11
3.4.4 Charging beacons and other details ........................................................................................................... 12
4. Setting up the system ........................................................................................................................................... 13
4.1 The very first setup routine of your device ..................................................................................................... 13
4.2 Setup software (Dashboard) ........................................................................................................................... 14
4.3 Using the syste after the very first setup ..................................................................................................... 19
4.4 DFU progra ing ........................................................................................................................................... 20
5. Interfaces ................................................................................................................................................................ 23
5.1 Beacon HW v4.9 external interface 4x4 pinout .............................................................................................. 24
5.2 Mode HW v4.9 external interface pinout .................................................................................................... 25
6. Advanced system settings and optimization ..................................................................................................... 26
6.1 Using oscilloscopes .......................................................................................................................................... 26
6.1.1 Monitor ultrasonic signal fro one beacon to another ............................................................................. 26
6.1.2 Proper ultrasonic signal detection .............................................................................................................. 27
6.2 Using hedgehog.log file ............................................................................................................................... 28
6.3 I portant aspects and hints ........................................................................................................................... 29
6.4 Deep hints ....................................................................................................................................................... 30
6.5 Powering beacons ........................................................................................................................................... 31
6.6 Different colors in the Dashboard enu ......................................................................................................... 32
6.7 Ultrasonic coverage ......................................................................................................................................... 32
6.8 Sub aps .......................................................................................................................................................... 32
7. Frequently Asked Questions ............................................................................................................................... 33
8. Contacts .................................................................................................................................................................. 33

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1.Version changes
V2017_05_20
- Cleaned up description and some corrections are added
- Description of HW v4.5 is removed from this manual and is given in the previous version of the
manual and can be found here:
http://www.marvelmind.com/pics/marvelmind_navigation_system_manual_HW_v4.5.pdf
- Description of HW v4.9 added
- Introduced plastic housing for beacons and modem
- Introduced 915MHz variant for the US market (HW v4.9 only)
- General updates and description improvements
V2016_05_21:
- Detailed description of HW v4.5 added (5-sensor beacon)
- New Dashboard with multiple sub-maps introduced
- Some less relevant older HW versions descriptions are removed
- General updates and description improvements

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2. Executive summary
Marvelmind Indoor Navigation System is off-the-shelf indoor navigation system designed for
providing precise (+-2cm) location data to autonomous robots, vehicles (AGV) and copters.
It can also be used for tracking other objects, where the mobile beacon can be installed, for
example, in virtual reality (VR) systems, helmets for construction workers or miners, etc.
The navigation system is based on stationary ultrasonic beacons united by radio interface in
license-free band. Location of a mobile beacon installed on a robot (vehicle, copter, human,
VR) is calculated based on the propagation delay of ultrasonic signal (Time-Of-Flight or
TOF) to a set of stationary ultrasonic beacons using trilateration.
Stationary beacons form the map automatically. No manual entering of coordinates or
distance measurement is required. If stationary beacons are not moved, the map is built only
once and then the system is ready to function after 7-10 seconds after modem is powered.
Key requirement for the system to function properly is:
- An unobstructed sight by a mobile beacon of three or more stationary beacons
simultaneously - for 3D (X, Y,Z) tracking
- An unobstructed sight by a mobile beacon of two stationary or more stationary
beacons simultaneously – for 2D (X,Y) tracking
- Distance to the nearest 2 or 3 beacons – not more than 30 meters

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Key capabilities:
Parameter Technical Specifications
Distance between beacons Up to 50 meters in lab conditions; Recommended distance in real-life - 30 meters
(Transducer4 to Transducer4 looking straight to each other and other transducers
are off)
Coverage area Up to 1000 m
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for Starter Set configuration
Coverage for larger territories done similar to cellular networks
Location precision
- Absolute: 1-3% of the distance to the beacons
- Differential precision: ±2 cm
Location update rate
- 0.5-45Hz
- Can be set manually
- Depends on the distance between mobile and stationary beacons (shorter
distance – higher update rate)
- Depends on the number of mobile beacons (update rate for 25Hz for 1 mobile
beacon => 25Hz/2 for 2 mobile beacons and 25Hz/3 for 3 mobile beacons)
- Depends on the radio interface profile (500kbps vs. 38kbps)
- Slightly depends on the number of stationary beacons – not like for mobile
beacons
Power supply
Internal: LiPol battery 1000mAh
- Battery lifetime totally depends on the usage
- Stationary beacon with 16Hz update rate => up to 72h (tested). With 1Hz
update rate => ~72h*16 => 1 month
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Mobile beacon with 8Hz update rate – 12h (tested)
External: microUSB – recommended for permanent use
Weight Mobile beacon from Starter set:
- 59 grams (including battery 1000mAh and housing and antenna 50mm)
-
27 grams (bare board w/o battery)
Beacon size Size: 55x55x33 mm (with 50mm antenna: 55x55x65mm)

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3.Basics of the system
3.1 What’s in the box
Starter Set:
- 4xStationary beacons
- 1xMobile beacon (aka “hedgehog”)
- 1xModem/Router
* Exact appearance may wary depending on the Hardware version. Characteristics are kept the same or better
unless specially noted

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3.2 Indoor GPS architecture
Marvelmind Indoor Navigation System provides high-precision (± 2 cm) indoor coordinates
for autonomous robots and systems (“indoor GPS”). Brief description of the key elements of
the system is given on scheme below:

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3.3 Indoor “GPS” syste – close-up and internal view
LiPol 3.7V
1000 Ah

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3.4 Syste ele ents
3.4.1 Stationary beacons
- Shall be mounted on walls and ceilings – usually, above the robot and ultrasonic sensors facing
down – to provide the most robust unobstructed coverage of ultrasonic signal to robot. However,
for automatic landing and indoor navigation of copters, for example, it is recommended to place
beacons on the floor/ground and install the mobile beacon horizontally downwards looking on
the belly of the copter
- Position for the beacons and angles of
positioning shall be chosen in such a way that
maximum coverage in ultrasonic is provided for
the maximum territory. Proper ultrasonic
coverage is the utmost important element for the
system to function effectively
- Stationary beacons emit and receive ultrasound,
when the map is being formed. And they only
receive the ultrasound, when the map is formed
and frozen
- Stationary beacons have no exterior difference
with mobile beacons
- Inertial measurement unit (IMU) is not installed
on the stationary beacons
- The mobile and stationary beacons can be easily
interchanged by selecting the option (Except for
IMU) in the Dashboard
- There are 433MHz and 915MHz versions available. Proprietary radio protocol is used for
communication and
synchronization. Other ISM
bands are available upon
request too
- Stationary beacon with
full-size 165mm
antenna (for 433 MHz)

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3.4.2 Mobile beacon (“hedgehog”)
-The mobile and stationary beacons can be easily interchanged by selecting the option in the
Dashboard
-The mobile beacons are designed to be placed on the robot vehicle or copter/drone or AGV
or helmet to trace its location. Formally speaking, location of the mobile beacon is traced –
not the robot itself. Since the sizes and the location of the central point of the mobile beacon
and the robot are different, the difference
has be taken into account in the robot’s
SW
-It is recommended to place the mobile
beacon horizontally to provide optimal
ultrasonic coverage in the upper
hemisphere
-Its sensors must not be covered with
anything that can reduce the strength of
ultrasonic signal. For example, they
system wouldn’t normally work, if one puts
the mobile beacon in a plastic box
-The beacon’s coordinates are updated
according to the rate set in the Dashboard
-System may contain one or several mobile
beacons. Current implementation relies on
time division multiple access approach.
Thus, if two mobile beacons are activated, they share the same system bandwidth. It means
that, if 16 Hz update rate is selected and there are 2 mobile beacons in the system, each
beacon’s location will be updated with the rate of 16Hz/2 ~ 8Hz. If there are 3 mobile
beacons => 16Hz/3 ~ 5Hz, etc. Future SW implementation may contain different solution
that will improve update rate in the setup with multiple mobile beacons
-Location data is obtained either from the “hedgehog” via USB (virtual UART), UART, SPI or
the modem/router via USB (virtual UART). More on interfaces:
http://www.marvelmind.com/#Interfaces
- Data from the beacon is sent in a streaming format identical that of GPS (NMEA 0183)
-There are 433MHz and 915MHz versions available. Proprietary radio protocol is used for
communication and synchronization
- The “hedgehog” has been successfully integrated with Windows PC, Linux machines,
Raspberry Pi, Arduino boards, Intel boards, etc: http://www.marvelmind.com/#Interfaces

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3.4.3 Mode /router
- The central controller of the system. It must be powered all the time, when the Navigation
System works. It is recommended to use active USB hub for that purpose or even a regular
USB power supply for cellular phones. A
USB power bank can be used too
- Modem is also used to setup the system,
monitor it, interact with the Dashboard
- It can be placed anywhere within radio
coverage to have permanent radio
connection with all beacons – usually in
the radius of up to 100 meters with
antennas from Starter Set
- The radio coverage can be further
extended to a few hundred meters by
using lower bitrate of 38kbps and full-
size (165mm – for 433MHz band)
antennas (tested up to 400 m in ideal
conditions)
- There are 433MHz and 915MHz versions
available
- Proprietary radio protocol is used for communication and synchronization

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3.4.4 Charging beacons and other details
−The Beacon has 5 sensors (transducers) RX1, RX2, RX3, RX4, RX5
−DIP switch modes:
1) Power = OFF, DFU = OFF: charging is possible; beacon is disconnected from
internal battery. This mode is recommended, if you want to keep the battery fully
charged for a long time and store the beacon on the shelf
2) Power = ON, DFU = OFF: normal working mode for beacon. The beacon is fully
powered and wakes up every a few seconds to monitor radio signal from the
modem. Power consumption is still minimal, if the beacon sleeps and the battery
can last for many weeks or months. It is recommended to keep the beacon in this
mode and to not touch the DIP switch at all, unless you want to store the beacon on
the shelf. Then, the mode 1) is better and recommended
3) Power = ON, DFU = ON: DFU programming mode. It is used for the very initial SW
uploading or when the HEX SW cannot be uploaded from the Dashboard for some
reasons
−Charging is done
automatically every
time, when the USB
charger is attached to
the board. LED 1 is
active
−It takes 1-2h to fully
charge the board’s
battery
−If you plan using
charger for permanent
powering of the
beacon, make sure
that the power source
is not noisy (+5V is
not noisy). The
performance can be
monitored by
Dashboard => View
=> Oscilloscope, visit
oscilloscope
paragraph
−When the board is
charged and turned
on LED 2 is blinking
every few seconds, if
to press reset and modem is active. If modem is not active or works on different radio
channel, the beacon automatically goes into a sleep mode in 1 minute

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4.Setting up the system
4.1 The very first setup routine of your device
The routine below describes the very first setup of the system. If you have done that already,
please, jump to the chapter Using the system after the very first setup below.
4.1.1 Unpack the system. Watch the help video: https://youtu.be/IyXB3UXHdeQ. Note that
the video is shot for the previous HW version 4.5
4.1.2 Check that your board is charged; see that all switches on beacons are in the
correct position (Power = ON; DFU = OFF). See paragraph detailed description and
charging
4.1.3 Press Reset button on beacon. If LED2 is not blinking, it means your board is turned
off or discharged. Check the position of DIP switch again or charge via USB; see
appropriate paragraphs for help

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4.2 Setup software (Dashboard)
4.2.1 After charging boards download the latest stable software package from
http://www.marvelmind.com/#Download
4.2.2 Select the SW version of the portable or distribution and unzip
4.2.3 Run the Dashboard and update the SW for all beacons and modem using
Dashboard => Firmware => Choose the file => Program
4.2.4 If you see message in the Dashboard “Not found modem connection to computer through
USB”, usually, it means that the driver is not installed. To install the driver, download it with link
at top and run installation file” click on the link under, install the driver
4.2.5 Ensure that
(a) You are programming modem’s SW to modem and beacon’s SW to beacon
(b) You are using SW for 4.9, if you have HW v4.9
(c) You have the SW from the same SW pack, i.e. the Dashboard SW and modem SW
and beacon SW must be from the same SW pack. Don’t mix SW releases
4.2.6 While beacon/modem is connected to the Dashboard, press Default button in the Dashboard to
upload the default settings. See the print screen below:

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4.2.7 Write down and use later the beacon’s address or change the addressed to your convenience as
shown here
4.2.8 Press RESET button on your beacons and modem after programming
4.2.9 After programming devices with the latest software, modem and beacons are ready for use.
Place stationary beacons on the walls vertically in such a way that optimal ultrasonic coverage is
provided. To start with the system it is recommended to use a simple room of 4x6 meters or so
and place the stationary beacons on the opposite walls on 1.85m height (default). After
familiarizing with the system far more complex configurations can be done. Here is the help
video
4.2.10 Connect the modem/router via USB to the Windows PC with the Dashboard installed.
4.2.11 Run the Dashboard
4.2.12 In the left corner of the Dashboard Modem shall appear connected
4.2.13 Wake up all beacons by clicking on the buttons in the Dashboard on the below panel
4.2.14 It may take up to 8 seconds for beacons to wake up
4.2.15 If modem is not active and is not powered, the beacons will go asleep automatically after 1
minute. The system may run for the frequency search, if it is you’re the very first waking up the
beacons. If doesn’t succeed with this step, disconnect the modem and connect that beacon
again via USB. Press the Default button in the Dashboard and Read all button to make sure that
the radio settings are really the default ones. You may compare the radio settings on the modem
and the radio settings on the beacon. They must be the same

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4.2.16 Now you can check the height position of the beacons, RSSI, radio channel, threshold etc. on
the panel in the right corner of the Dashboard
4.2.17 Notice, that there are 99 beacon’s addresses available. If you don’t see some of your connected
beacons on the map, scroll it so you will be able to find their addresses
4.2.18 Also double click on the device to go into sleeping mode and double clicking to wake up
4.2.19 The map will form automatically and zoom in automatically
4.2.20 If the map does not form well. Check the Table of distances in the left corner of the Dashboard.
Cells must be colored in white; it means the distances between stationary beacons are
measured correctly.

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If you see in the table some empty cells or marked yellow/red, it is an indication that distances between
some beacons are measured inconsistently or not measured at all. Try to check what the problems with
those beacons are. Try to re-position them, because, usually, there is an obstruction of some sort in the
between the beacons. Reset them.
Use View => Table of distances to monitor the measured distances between beacons
4.2.21 Freeze the map by clicking the button. Stationary beacons will stop measuring relative distances
and will be ready to measure distance from the mobile beacon(s)
4.2.22 Turn on and wake up mobile beacon similar to the operations with the stationary beacon:
https://youtu.be/A4aRsjH2-_E

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4.2.23 If you see on the devices’ panel beacon colored orange, it means some settings between
beacons are different, for example: some sensors are off or some ultrasonic or radio settings are
different. You can change the settings for sensors manually by clicking on the panel in the right
corner of the dashboard and make grey cells green to turn on sensor. But for starting, it is very
much recommended to use default settings on all beacons and modem
4.2.24 After you froze the map of stationary beacons, wake up the mobile beacon. After it wakes up, it
will be traceable in 5-7 seconds
4.2.25 By now, the system must be fully operational

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4.3 Using the syste after the very first setup
4.3.1 If you had setup the drivers, built and froze the map and hadn’t moved stationary beacons,
in order to start using the system again, you simply have to power up the modem. The map
is stored inside the modem and the system will be ready to handle your mobile beacons in 5
seconds after that
More help you can find here: https://www.youtube.com/channel/UC4O_kJBQrKC-NCgidS_4N7g/videos

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4.4 DFU progra ing
DFU programming or SW uploading is used when HEX SW uploading in the Dashboard cannot
be used, for example, when you update from a very old SW version or when the SW brings so
much change to the system that it is possible to update the SW only via DFU programming
4.4.1 To start programming, move the beacon’s DIP switch in the DFU programming mode, as
described in the paragraph DIP switch modes
4.4.2 Download the latest SW package, unpack it and select the proper version of the SW – for
your HW and for your frequency variant. Remember, that for DFU programming you shall
use DFU SW – not HEX SW
4.4.3 Download: http://www.marvelmind.com/downloads/Software.zip
4.4.4 Use DFU programmer and upload DFU SW into beacon:
- Install DFU driver
http://www2.st.com/content/st_com/en/products/development-tools/software-
development-tools/stm32-software-development-tools/stm32-programmers/stsw-
stm32080.html
- Install DfuSe SW 3.04 (or 3.0.3 or 3.0.5) - whatever works the best for your
Windows
- http://www. arvel ind.co /downloads/DFU/DfuSe_De o_V3.0.5_Setup.exe
- Connect beacon via USB to PC
- Run DfuSe SW before starting the Dashboard
- Press RESET button on your beacon
- You will see in the upper left corner of the DfuSe program a device connected in the
DFU mode
- Choose the DFU driver for the beacon from the 1 step downloaded and unpacked
SW package (2 step on pic)