Difference between revisions of "Paul Cox Notes"
| Line 99: | Line 99: | ||
==Sept 30 == | ==Sept 30 == | ||
==Using a | ==Using a joystick to control twog servo== | ||
===PC-side configuration=== | ===PC-side configuration=== | ||
| Line 105: | Line 105: | ||
: 1. Running an ocaml application that listens to the joystick device and using a configuration file, will send ivy messages that get forwarded to the vehicle by the server. | : 1. Running an ocaml application that listens to the joystick device and using a configuration file, will send ivy messages that get forwarded to the vehicle by the server. | ||
: 2. Normal paparazzi settings mechanism (using settings dialog on PC) that sets corresponding variables on the vehicle. | : 2. Normal paparazzi settings mechanism (using settings dialog from paparazzi center running on PC) that sets corresponding variables on the vehicle. | ||
Running the test program you can see which buttons do what: | Running the joystick test program you can see which buttons do what: | ||
(Note you have to run a make in the directory first to compile everything) | (Note you have to run a make in the directory first to compile everything) | ||
| Line 198: | Line 198: | ||
<field name="ac_id" type="uint8"/> | <field name="ac_id" type="uint8"/> | ||
</message> | </message> | ||
</pre> | |||
To send settings use the actuators.xml file: | |||
<pre> | |||
<settings> | |||
<dl_settings NAME="Actuators" > | |||
<dl_setting VAR="actuators[1]" MIN="900" STEP="1" MAX="2100" module="actuators" shortname="chan1"/> | |||
<dl_setting VAR="actuators[2]" MIN="900" STEP="1" MAX="2100" module="actuators" shortname="chan2"/> | |||
<dl_setting VAR="actuators[3]" MIN="900" STEP="1" MAX="2100" module="actuators" shortname="chan3"/> | |||
<dl_setting VAR="actuators[4]" MIN="900" STEP="1" MAX="2100" module="actuators" shortname="chan4"/> | |||
<dl_setting VAR="actuators[5]" MIN="900" STEP="1" MAX="2100" module="actuators" shortname="chan5"/> | |||
<dl_setting VAR="actuators[6]" MIN="900" STEP="1" MAX="2100" module="actuators" shortname="chan6"/> | |||
<dl_setting VAR="actuators[7]" MIN="900" STEP="1" MAX="2100" module="actuators" shortname="chan7"/> | |||
</dl_settings> | |||
</settings> | |||
</pre> | </pre> | ||
===Vehicle-side configuration=== | ===Vehicle-side configuration=== | ||
On the vehicle side we are using a twog for hardware so we will use the setup_actuators target found in | On the vehicle side we are using a twog for hardware so we will use the setup_actuators target found in /conf/autopilot/setup.makefile. | ||
This makefile is used by the tiny.makefile which is used because we specify we're using the twog in twinjet_overo.xml | This makefile is used by the tiny.makefile which is used because we specify we're using the twog in twinjet_overo.xml | ||
| Line 211: | Line 225: | ||
</pre> | </pre> | ||
The setup target is defined as follows: | The setup target is defined as follows in the airframe (twinjet_overo.xml): | ||
<pre> | <pre> | ||
<firmware name="setup"> | <firmware name="setup"> | ||
| Line 220: | Line 234: | ||
If we were adding the joystick to the autopilot code we could instead add the following line to the firmware section: | If we were adding the joystick to the autopilot code we could instead add the following line to the firmware section: | ||
: <subsystem name="joystick"/> | |||
but that's another project... | |||
Here's the setup.makefile section that worked for me: | Here's the setup.makefile section that worked for me: | ||
| Line 232: | Line 246: | ||
setup_actuators.srcs += sys_time.c $(SRC_ARCH)/sys_time_hw.c $(SRC_ARCH)/armVIC.c pprz_transport.c downlink.c actuators.c setup_actuators.c $(SRC_ARCH)/uart_hw.c $(SRC_ARCH)/servos_4017_hw.c main.c | setup_actuators.srcs += sys_time.c $(SRC_ARCH)/sys_time_hw.c $(SRC_ARCH)/armVIC.c pprz_transport.c downlink.c actuators.c setup_actuators.c $(SRC_ARCH)/uart_hw.c $(SRC_ARCH)/servos_4017_hw.c main.c | ||
</pre> | </pre> | ||
= Summer 2010 = | = Summer 2010 = | ||
Revision as of 07:53, 1 October 2010
Paul Cox Build Log
LISTS
| Num | Name | Notes | Priority | Status | |
|---|---|---|---|---|---|
| 1 | Add a task #1 | x | In progress :-) | ||
| 2 | decode PPM on Lisa | x | x | ||
| 3 | read battery levels on Lisa | x | x | ||
| x | Test Overo/Tiny SPI communication | Tested, need to add timeout/restart and checksum | x | Done | |
| x | get edimax working with gumstix | needed rt3070 driver, Allen has pushed my changes | x | done | |
| x | Create PCB to interface beth azimuth pot | beth board 1 built, tested, installed | x | Done | |
| x | Create PCB to interface tilt/elevation | beth board 2 built, tested, installed | x | Done | |
| x | Send telemetry from overo over wifi | works well, but some wifi sticks give error when high throughput required | x | Done | |
| x | Use event periodic call in main overo task for precise timing | Used fms_test_periodic as example | x | Done | |
| x | Update to new CAN implementation | x | x | Done | |
| x | Implement PID on Beth | x | x | x | |
| x | Implement Kalman on Beth | x | x | x | |
| x | Implement feedback lin. control on Beth | x | x | x | |
| x | Receive datalink with overo through wifi | x | x | Done | |
| x | Create ipkg to install and setup gumstix | libraries, utilities, scripts to setup in ro, , etc | x | x | |
| x | add SPI checksums | use STM32 spi checksum offload capability | x | x
| |
| x | x | x | x | x |
| Num | Name | Notes | Priority | Status |
|---|---|---|---|---|
| 1 | Get foam plane flying | Electronics mostly installed, more few manual flights | x | In Progress |
| 2 | Paparazzi Documentation | Started outlining here | x | Started |
| 7 | Try Web-based GCS | x | x | x |
| 8 | Improve altitude control loop | issue with hard boundary between PI and constant regions | x | x |
| 9 | Some camera stabilization | Read gimbal servo positions via pot tap to ADC | x | x |
| 10 | Try then document item drop capability | x | x | x |
| Num | Name | Notes | Priority | Status |
|---|---|---|---|---|
| 1 | RC Transmitter | x | x | x |
| 2 | Camera for Overo | x | x | x |
| 3 | Booz system | x | x | x |
| Num | Name | Notes | Priority | Status |
|---|---|---|---|---|
| 1 | RC Transmitter with embedded GCS on 4-5" LCD | Compile GCS on ARM (beagle/overo/nokia tablet) | x | x |
| x | x | x | x | x |
| x | x | x | x | x |
Sept 30
Using a joystick to control twog servo
PC-side configuration
On the PC side we will send actuator commands two different ways:
- 1. Running an ocaml application that listens to the joystick device and using a configuration file, will send ivy messages that get forwarded to the vehicle by the server.
- 2. Normal paparazzi settings mechanism (using settings dialog from paparazzi center running on PC) that sets corresponding variables on the vehicle.
Running the joystick test program you can see which buttons do what: (Note you have to run a make in the directory first to compile everything)
~/paparazzi3/trunk/sw/ground_segment/joystick$ ./test_stick Available button: 288 (0x120) Available button: 289 (0x121) Available button: 290 (0x122) Available button: 291 (0x123) Available button: 292 (0x124) Available button: 293 (0x125) Available button: 294 (0x126) Available button: 295 (0x127) Available button: 296 (0x128) Available button: 297 (0x129) Available button: 298 (0x12a) Available button: 299 (0x12b) Available axis: 0 (0x0) Available axis: 1 (0x1) Available axis: 2 (0x2) Available axis: 5 (0x5) Available axis: 16 (0x10) Available axis: 17 (0x11) Available axis: 40 (0x28) Axis 0 : parameters = [0,255] Axis 1 : parameters = [0,255] Axis 2 : parameters = [0,255] Axis 3 : parameters = [0,255] Axis 4 : parameters = [-1,1] Axis 5 : parameters = [-1,1] Axis 6 : parameters = [0,255] Input device name: "GreenAsia Inc. USB Joystick " on device "/dev/input/event6" buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 127 0 0 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 87 0 0 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 20 0 0 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 69 0 0 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 127 0 0 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 127 0 0 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 0 0 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 0 0 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 0 0 127 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 0 111 48 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 0 127 -64 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 -127 32 -127 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 -127 -39 -69 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 0 -117 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 0 -127 127 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis -127 40 -35 127 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis -127 49 127 127 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis -127 127 127 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis -53 127 127 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 8 127 0 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 127 84 0 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 0 0 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 0 0 0 0 0 127 0 0 0 buttons 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 0 0 0 0 0 127 0 0 0 buttons 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 0 0 0 0 0 127 0 0 0 buttons 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 | axis -127 -66 0 0 0 0 127 0 0 0 buttons 1 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 | axis -127 0 0 0 0 0 127 0 0 0 buttons 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 127 0 0 0 0 127 0 0 0 buttons 1 1 0 0 0 1 0 0 0 0 0 0 0 0 0 0 | axis 47 127 0 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 59 127 0 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 0 0 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 0 0 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis -105 -127 0 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis -78 -127 0 0 0 0 127 0 0 0 buttons 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 -99 0 0 0 0 127 0 0 0 buttons 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | axis 0 0 0 0 0 0 127 0 0 0
Then creating an xml configuration file such as:
paul@ledelle:~/paparazzi3/trunk/sw/ground_segment/joystick$ medit ngs_set_actuators.xml
and now running the input2ivy ocaml application:
export PAPARAZZI_HOME=/home/paul/paparazzi3/trunk paparazzi3/trunk/sz/ground_segment/joystick/input2ivy -ac TJOVERO ngs_set_actuators.xml
running ivyprobe we can see the message getting transmitted:
paul@ledelle:~/paparazzi3/trunk/sw/ground_segment/joystick$ ivyprobe '(.*)'
shows:
Paparazzi joystick sent 'input2ivy SET_ACTUATOR 1496 2 3'
but we have to make sure the server knows this message needs to be forwarded: in messages.xml the message should be labeled as "forwarded" :
<message name="SET_ACTUATOR" id="100" link="forwarded"> <field name="value" type="uint16"/> <field name="no" type="uint8"/> <field name="ac_id" type="uint8"/> </message>
To send settings use the actuators.xml file:
<settings>
<dl_settings NAME="Actuators" >
<dl_setting VAR="actuators[1]" MIN="900" STEP="1" MAX="2100" module="actuators" shortname="chan1"/>
<dl_setting VAR="actuators[2]" MIN="900" STEP="1" MAX="2100" module="actuators" shortname="chan2"/>
<dl_setting VAR="actuators[3]" MIN="900" STEP="1" MAX="2100" module="actuators" shortname="chan3"/>
<dl_setting VAR="actuators[4]" MIN="900" STEP="1" MAX="2100" module="actuators" shortname="chan4"/>
<dl_setting VAR="actuators[5]" MIN="900" STEP="1" MAX="2100" module="actuators" shortname="chan5"/>
<dl_setting VAR="actuators[6]" MIN="900" STEP="1" MAX="2100" module="actuators" shortname="chan6"/>
<dl_setting VAR="actuators[7]" MIN="900" STEP="1" MAX="2100" module="actuators" shortname="chan7"/>
</dl_settings>
</settings>
Vehicle-side configuration
On the vehicle side we are using a twog for hardware so we will use the setup_actuators target found in /conf/autopilot/setup.makefile. This makefile is used by the tiny.makefile which is used because we specify we're using the twog in twinjet_overo.xml
<firmware name="fixedwing">
<target name="ap" board="twog_1">
The setup target is defined as follows in the airframe (twinjet_overo.xml):
<firmware name="setup">
<target name="tunnel" board="twog_1" />
<target name="setup_actuators" board="twog_1" />
</firmware>
If we were adding the joystick to the autopilot code we could instead add the following line to the firmware section:
- <subsystem name="joystick"/>
but that's another project...
Here's the setup.makefile section that worked for me:
setup_actuators.CFLAGS += -DFBW -DLED -DTIME_LED=1 -DACTUATORS=\"servos_4017_hw.h\" -DSERVOS_4017 setup_actuators.CFLAGS += -DUSE_UART1 -DUART1_BAUD=B57600 -DDOWNLINK_DEVICE=Uart1 -DPPRZ_UART=Uart1 setup_actuators.CFLAGS += -DDOWNLINK -DDOWNLINK_TRANSPORT=PprzTransport -DDATALINK=PPRZ setup_actuators.CFLAGS += -DDOWNLINK_FBW_DEVICE=Uart1 -DDOWNLINK_AP_DEVICE=Uart1 setup_actuators.srcs += sys_time.c $(SRC_ARCH)/sys_time_hw.c $(SRC_ARCH)/armVIC.c pprz_transport.c downlink.c actuators.c setup_actuators.c $(SRC_ARCH)/uart_hw.c $(SRC_ARCH)/servos_4017_hw.c main.c
Summer 2010
Develop beth detailed on Beth Test Bench page and overo/twog com detailed on overo page.
Aug 4
Some parameters I'm now using on beth:
- link -udp -transport pprz2
- server -no_md5_check option
- settings -ac BETH
other useful stuff:
- ivyprobe '(.*)'
- export PPRZ_DEBUG='*'
- export PAPARAZZI_HOME=/home/paul/paparazzi3/trunk
- export PAPARAZZI_SRC=/home/paul/paparazzi3/trunk
June 2010
June 23
Compile beth projects :
main overo - reads/writes SPI main_stm32 - runs on lisa STM. fetches values on I2C from olimex board, sends to overo main_coders - runs on Olimex header board. samples ADCs sends messages out of UART for debug and I2C slave
Seeing issue where lisa stm32 crashes randomly. seems to occur less often if periodic loop less frequent (for example reduce from 512 to 256 or 64)
attempt to debug with logic analyzer from saleae.com
June 22
Finish Beth schem/pcb take to ENAC with steel axle
available from:
http://code.google.com/p/enac-lara/source/browse/#svn/trunk/paul/beth
June 21
rt2780usb
Tried to get rt2780usb wifi dongle working with lisa, no luck : the adapter is recognized at some level as I get the following messages :
output from gumstix
usb 1-1.4: new high speed USB device using musb_hdrc and address 6 usb 1-1.4: New USB device found, idVendor=7392, idProduct=7711 usb 1-1.4 : New USB device strings: Mfr=1, Product=2, SerialNumber=3 usb 1-1.4: Product: 802.11 n WLAN usb 1-1.4: Manufacturer: Ralink usb 1-1.4: SerialNumber: 1.0 lsmod output: Module Size Used by ipv6 219420 1 0 rt73usb 20604 0 rt2x00usb 9154 1 rt73usb sg 21442 0 rt2x00lib 26540 2 rt73usb,rt2x00usb ads7846 8395 0
output from karmic pc:
[221517.285099] usb 1-4: new high speed USB device using ehci_hcd and address 62 [221517.440249] usb 1-4: configuration #1 chosen from 1 choice [221517.476238] phy8: Selected rate control algorithm 'minstrel' [221517.481524] Registered led device: rt2800usb-phy8::radio [221517.481663] Registered led device: rt2800usb-phy8::assoc [221517.481793] Registered led device: rt2800usb-phy8::quality [221518.171887] udev: renamed network interface wlan0 to wlan13 [221518.213665] rt2800usb 1-4:1.0: firmware: requesting rt2870.bin [221518.746845] ADDRCONF(NETDEV_UP): wlan13: link is not ready
Since the adapter works perfectly on my karmic pc and I noticed that there a firmware bin file was being requested, i copied it over to the gumstix in /lib/firmware but still no luck. I tried the latest prebuilt binary image (June 18) from gumstix and still the same behavior. Perhaps I need to configure something...
USB OTG as host testing
Interfaced a hub to the USB OTG port. bridge the ID pin to GND and run USB+/- and VBUS to the hub. Supposedly hot-swapping is not supported (must boot with device plugged in already) but that could be an old issue and that works now.
June 17
Setting up paparazzi source and OpenEmbedded to compile for LISA:
sudo apt-get install paparazzi-stm32 sudo apt-get install gtkterm ls .ssh/id_rsa.pub cat .ssh/id_rsa.pub vi /home/paul/.subversion/servers ===================================== Uncommented : [groups] group1 = * ### Information for the first group: [group1] http-proxy-host = squid http-proxy-port = 3128 ===================================== svn co svn+ssh://paulcox@svn.savannah.nongnu.org/paparazzi/paparazzi3 cd trunk make cd paparazzi3/conf/ ls gedit conf.xml vi conf/airframes/Poine/booz2_a7.xml vi conf/autopilot/lisa_test_progs.makefile vi conf/Makefile.omap sudo cp conf/system/udev/rules/10-paparazzi.rules /etc/udev/rules.d/ sudo /etc/init.d/udev restart sudo vi /opt/paparazzi/stm32/share/openocd/scripts/interface/openocd-lisa-jtag.cfg make AIRCRAFT=BOOZ2_A7 test_led.upload vi conf/airframes/Poine/beth.xml make AIRCRAFT=BOOZ2_A7 overo_test_periodic.upload make AIRCRAFT=BETH overo_test_link_stm.upload ssh-copy-id paul@auto7 ssh auto7 ./overo_test_link_stm.elf
Used gtkterm to connect to ttyUSB0/1? to connect to Overo console. login as root with no password. ran dhclient wlan0.
Jan 2010
Had to pack up all my stuff this summer and just now starting to get back into UAVing. First on the list is to get a plane in the air. I brought most my electronics with me, and the lab is letting me use a foam plane so I should be flying soon. I'm also hoping to start on quadrotors so I can get more familiar with them and help document it. Other things on the task list: Design a tiny with an overo SPI connection.
Nov 2008 - Jan 2009
Installing Software on Ubuntu Intrepid Ibex 8.10
Used CVS to download "paparazzi3". also discovered Booz guys are using svn and that repository is called "paparazzi4".
Read the wiki multiple times through, built everything acording to instructions, and fired off the program which seems to run in simulator mode, although
I'm currently not seeing any action when I hit the "Launch" button. I probably haven't read something important somewhere...
Gather hardware:
Looked at the hardware designs in CVS to see if I wanted to customize a design or build one of the "released" designs. In summary, the current things
folks are building and using are:
Autopilots
- Tiny 1.3 - ARM processor and GPS on 4 layer PCB with 0402. Benefits: smaller and 4 layers is more reliable Drawbacks: Design is older and has
evolved so there are some missing feature and maybe some issues (Insert more specifics here as I learn them)
- Tiny 2.11 - ARM processor and GPS on 2 layer PCB with 0603 SMT devices.
- TWOG - Tiny 2.11 without GPS. I assume people want to branch out and use different GPS and not just the u-blox stuff. Also I see mention that some
people want to mount GPS hardware some place different on their airframe than where the autopilot resides.
- Booz - Some very exciting quadrotor developments. HW Design not checked yet as there's some errata that someone feels like needs to be fixed before it
is commited.
Sensors
- Single Axis IR - For two Melexis thermopiles
- Dual Axis IR - For four Melexis thermopiles
- GPS board - A PCB to hold just a GPS and an antenna. For use with TWOG
Looked at how much to have the PCBs fab'ed by quick turn board house, but unless you order 25 or more PCBs you're better off buying from the listed
vendors. I went with PPZUAV:
- single IR PCB $8
- Dual IR PCB $8
- Tiny 1.3 PCB $9.95
- Tiny 2.11 PCB $5
$6.80 shipping (California to Washington)
I check first to make sure all was in stock, and David replied that it was. Order took a couple days to process and a few days for the post office to
deliver the priority lettter. PCBs arrived in a little padded envelope and even though I knew the dimensions before, I was surprised at how small they
are in the flesh.
Components were mostly from Digikey: TI DC/DC was only available in SMT and no shotkeys.
Complete List: (insert spreadsheet here)
Mouser had the switching DC/DC in through-hole and shotky diode so put in an order with them as well:
Of note: Looked for GPS modules and antenna and found some items of interest. A Tyco GPS module with a built in antenna for $60 []. Also antenna [].
Different center frequencies are available 1575 MHz and 1579 MHz, but googling seems to show that 1575 is the main GPS freq. Not sure what 1579 is useful
for, but it kinda looks like the one paparazzi recommends from their testing is centered at 1579 so I must be missing something.
Complete List: (insert spreadsheet here)
While waiting for all the hw to arrive, built a wireless GPS device:
Main components:
Wireless modem: XBee Pro 802.15.4 (XBP-24-AUI) GPS: Battery: 2S Lipo (gutted Axim x50v battery, rewired from parallel to series) Antenna: Some rpsma? wifi antenna I had laying around with a u.fl connector/pigtail.
Other components TI DC/DC converter (same as used on tiny) 100uF tantalum capacitor (TI DC/DC conv requires this on the input) SPDT toggle switch Samtec mating connector for GPS kynar wire plastic box and some thin model plywood for a case
Receiver is another XBee Pro in a USB carrier board. The XBee Pro has a wire antenna (XBP-24-?UI). Looking back I should have ordered with the RP-SMA so
I can put some coax on there to a big honkin' antenna to improve range.
Build process: Main obstacle here is the fine pitch connector on the GPS module.
XBee Pro and the GPS module are 3.3V devices. For the TI DC/DC used on Tiny to produce 3.3V a 1.87kOhm resistor is needed an input capacitor of 100uF is
needed. I wired up all these components
Bring up process:
Getting things talking was suprisingly easy. XBee devices come pre-programmed and configured for transparent mode at 9600bps. There's destination and
source addresses and all sorts of configurable stuff, but out of the box two XBee will just find and talk to each other (great job guys!). Transparent
mode basically means that both the devices send traffic to each other transparently, so essentially the end devices don't need to know anything since the
XBees just look like a wire.
The GPS module provides NMEA data at 4800 baud so I needed to reconfigure the XBees for that lower baud rate (I may not have needed to do both, but I did
anyways). Doing that involves getting out of transparent mode and into command mode (done by sending characters "+++") at which point a few "AT" commands
are used to change the rate and save the setting to non-volatile memory.
By the way, Digi also makes a windows application available called "X-CTU" which is very useful. It will test communication with your XBee device,
read/write the module's settings, and has two other very useful modes: A range test mode where the the Xbee on the far side of the link has had it's
RX/TX pins wired together for loopback and signal strength is displayed; and a terminal emulator that works nicely (I had a heck of a time finding a good
terminal program that worked with my COM26 device, looked good, and was easy to use. No matter how much .ini hacking I did I couldn't get teraterm to
look beyond 4 ports).
So first to validate that my DC/DC is providing power and the GPS works, I hooked up a GPS to a serial/USB converter (from acroname) to the GPS RX/TX
pins and plugged the USB cable into my laptop. Turn on power and sure enough, lots of NMEA looking stuff spews forth. Next rewired the GPS to the XBee
and plugged the USB/XBee device into the laptop and, voila, same data shows up as before but this time the GPS device is totally wireless.
Now I wanted to get more than just a bunch of NMEA strings on a terminal window, I wanted to see the position in google earth or google maps. I bought
the plus version of google earth and had used it with my Garmin Etrex Vista successfully, but it turns out that it doesn't work directly with an NMEA COM
port based device (at least for me). Instead, there are a number of folks out there that provide little command line programs that open the com port and
crank the data out in xml via http socket. Google earth can open a network location.
Tiny v2.11 Assembly Process
Once all parts arrive: sorting components and getting BOM and component placement references ready for use. Wiki has all this info nicely laid out.
- PCB silkscreen and wiki image (
) have LED1 and LED2 reversed. Not sure which is correct yet.
Since there's more components on the CPU side, that's the side I populate first. Starting with smallest components to largest makes assembly the fastest.
Once all components mounted and the input power wires are soldered, time to apply power. I used a benchtop power supply so I could monitor current.
With a voltage input of 7.0V, current should be around 50? mA.
Now attach IR sensor boards and USB connector along with wires for other interfaces (serial, download, rc receiver -- I'm waiting before doing servo
wires to keep things tidy until later)
First order of business is to download USB bootloader over the serial port. This uses the "Download" serial port so you have to disable the GPS, but I
hadn't populated it yet so didn't have to bother with disabling it.
Now that there's a USB bootloader, downloading code into Tiny just requires plugging in the USB cable, powering up, and sending the code (which is either
done with a "make" command or pressing the "Upload" button in Paparazzi Center.
Now to run a simple program: LED test. Some nice instructions on getting this going are [here].
All goes well and three LEDs are blinking.
Now download autopilot code. A direct connection of the serial port to a USB-serial adapter plugged into my PC relays the telemetry data. Firing
Paparazzi Center and executing the session "Flight USB-serial@9600" shows battery voltage so I'm up and running.
Now I attach the IR boards
Mounting
Things are getting sloppy and afraid something will short and fry, so it's time to mount things to get things under control. I had some plastic cases that some lenses came in which happen to be just the right size. Tiny, my 2S lipo, and an XBee fit in one side perfectly, and the other side can be used for extra wires, the USB connector, power switch, and the RC Receiver. The IR sensors are hot-glued on the exterior using a little balsa. Probably won't be useful when it comes time to fly, but it's compact and sturdy which is what I need until I'm ready to start thinking about flying...
Configuration
I started with the funjet1.xml airframe file because I read others use that with the Tiny2.11. I don't plan to use a dual elevon plane (instead will do a
standard rudder/elevator/ailerons setup) so will have to make lots of changes -- not a bad way to learn how things work... The
Airframe Configuration page is a great help here.
- Battery voltage - The default looks to be setup for a 3S battery and perhaps my resistor devider resistors aren't the right values, so GCS reports
incorrect battery voltage. Instead of hunting through the code I vary the voltage on my power supply, watch the output, and empiracally find the correct
values to set:
<section name="BAT"> <define name="MILLIAMP_PER_PERCENT" value="0.86"/> <define name="VOLTAGE_ADC_A" value="0.0245"/> <define name="VOLTAGE_ADC_B" value="0.1"/> <define name="VoltageOfAdc(adc)" value ="(VOLTAGE_ADC_A * adc + VOLTAGE_ADC_B)"/> <define name="CATASTROPHIC_BAT_LEVEL" value="6.4" unit="V"/> <define name="CRITIC_BAT_LEVEL" value="6.8" unit="V"/> <define name="LOW_BAT_LEVEL" value="7.0" unit="V"/> <define name="MAX_BAT_LEVEL" value="8.4" unit="V"/> </section>
- IR:
- Mode - I change from to tilted to aligned mode because tilted mode seems weird.
- IR:
remove:
<define name="HORIZ_SENSOR_TILTED" value="1"/>
add:
<define name="HORIZ_SENSOR_ALIGNED" value="1"/>
- Neutrals - The "cupboard test" shows the neutral values are pretty close already.
- Direction - Tilting the sytem around, I see that one of the axes is reversed so I set IR2_SIGN and TOP_SIGN values accordingly:
insert here
- GPS - For LEA-5H u-blox module: add -DGPS_USE_LATLONG in makefile portion of airframe xml file as per instructions on wiki []. I still get some error
messages, but they stop after a few seconds and all seems to work.