Difference between revisions of "Future Autopilots"

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== Tiny 2.0 is in development! ==
{| align=right
[[Image:tiny11vs20.gif|thumb|Eagle screencap comparing the current Tiny 1.1 to the new 2.0 version]]Antoine began a complete re-reouting of the Tiny autopilot on November 2, 2006.  The new design is not a bug-fix as no known flaws exist with the current 0.99 and 1.1 versions, so the redesign is purely performance-oriented!  [http://cvs.savannah.gnu.org/viewcvs/paparazzi/paparazzi3/hw/in_progress/ Download the Eagle files]
|-
=== Planned feature additions ===
|<categorytree style="float:right; clear:right; margin-left:1ex; border: 1px solid gray; padding: 0.7ex;" mode=pages>Autopilots</categorytree>
* Hardware flow control on the modem
|}
*: The LPC has one "full-featured" serial port and one basic serial port.  Current versions have the full-featured port hard-wired to the GPS in order to leave the basic port open for initial bootloader programmingTiny 2.0 will exchange these ports and add test points to disconnect the GPS for the one-time bootloader programming.
 
* TI PTH08080WAS switching 5V/2.25A regulator
== Proposed additions ==
*: This integrated power supply will greatly simplify manufacturing, reduce costs, and improve performance.  Tiny 2.0 will have a voltage input range of 6-16V and enough 5V power for large servos and high-power modems and video systems.
We're always looking for great ideasIf you'd like to see something added or changed on ''Tiny v2.11'' list it here! Please keep your suggestions relevant to ''this revision'' and post other requests in the [[Hardware_Wish_List|Hardware Wish List]].
* Larger GPS ground plane and antenna
 
*: The 13mm antenna on Tiny 1.1 proved to be an unworthy exchange of performance for weight.  Crude parking-lot tests showed an approximate 3dBi loss (as expected from the data sheets), but the narrow bandwidth of the small antenna made it more sensitive to de-tuning from nearby components in the aircraft. Flight performance was acceptable but poor climb rate calculations were observed with the smaller antenna.  Tiny 1.1 users are advised to fit a 20mm antenna.  Tiny 2.0 will use a 20mm x 4mm or 18mm x 4mm antenna and will feature 35% more ground plane area.
* Connector changes
*: Tiny 2.0 will feature revised header layouts on all peripherals.  The modem header will have CTS/RTS and both 5V and 3V supplies (3V is shared with LPC and ADC channels - use with caution and only with very low power modems like the 10mW Xbee).
*:The button will be removed and it's function will be combined on the USB header along with an LED trigger so that indicator, button, and USB can be remotely mounted.
* Separate GPS Option
* Separate GPS Option
*: To provide more flexible airframe installation, EMI trouble resolution, and GPS hardware optimization, a second version of Tiny 2.0 will be created with no GPS receiver or antenna.  This model will feature a 4-pin serial port to connect to the external GPS and will not require test points
: see [[TWOG/v1.0]]
=== Proposed additions ===
 
We're always looking for great ideas.  If you'd like to see something added or changed on ''Tiny 2.0'' list it here!  Please keep your suggestions relevant to ''this revision'' and post other request in the [[hw_Wish_list|Wish List]].
* EMI filters on ADC channels [[Image:EMI_Filter_NUF4220.gif|thumb|On Semiconductor NUF4220MNT1G 4-line EMI Filter]]
* EMI filters on ADC channels [[Image:EMI_Filter_NUF4220.gif|thumb|On Semiconductor NUF4220MNT1G 4-line EMI Filter]]
*: Analog sensors are severely affected by video and modem RF.  We typically see ADC reading fluctuations of +/-0.5% in a well shielded installation, but a misbehaving video transmitter or a noisy Radiotronix modem can affect ADC channels by more than 50% in the same well shielded installation.  The addition of effective filters to the ADC inputs should greatly reduce the effects of RFI and allow for a much broader range of RF equipment and airframe configurations.
: Analog sensors are severely affected by video and modem RF.  We typically see ADC reading fluctuations of +/-0.5% in a well shielded installation, but a misbehaving video transmitter or a noisy Radiotronix modem can affect ADC channels by more than 50% in the same well shielded installation.  The addition of effective filters to the ADC inputs should greatly reduce the effects of RFI and allow for a much broader range of RF equipment and airframe configurations.
*# I suggest the [http://www.onsemi.com/PowerSolutions/product.do?id=NUF4220MNT1G On Semiconductor NUF4220MNT1G].  A 2mm x 2mm chip that filters 4 analog signals, attenuatiing RF frequencies above 16 Mhz but particularly the 800 Mhz to 5 Ghz range. [[User:Jeremy|(Jeremy)]]
:I suggest the [http://www.onsemi.com/PowerSolutions/product.do?id=NUF4220MNT1G On Semiconductor NUF4220MNT1G].  A 2mm x 2mm chip that filters 4 analog signals, attenuatiing RF frequencies above 16 Mhz but particularly the 800 Mhz to 5 Ghz range. [[User:Jeremy|(Jeremy)]]
*#:<small>NUF4220MN is a 4 line LC EMI filter array designed for audio applications. It offers greater than -30 dB attenuation at frequencies from 800 MHz to 5.0 GHz, with no line loss. This part is a single chip solution for audio interface applications, 2 speaker lines with a microphone line. This device also offers ESD protection-clamping transients from static discharges and ESD protection is provided across all capacitors. </small>
:<small>NUF4220MN is a 4 line LC EMI filter array designed for audio applications. It offers greater than -30 dB attenuation at frequencies from 800 MHz to 5.0 GHz, with no line loss. This part is a single chip solution for audio interface applications, 2 speaker lines with a microphone line. This device also offers ESD protection-clamping transients from static discharges and ESD protection is provided across all capacitors. </small>
 
* Decoupling capacitor on GPS antenna
* Decoupling capacitor on GPS antenna
*: The u-blox reference design calls for a 47pF 10% 0603 capacitor in series between the receiver and antenna.  I have no idea why this is useful but apparently it must be, because this technique is commonly seen on WiFi cards, video transmitters, modems, even R/C receivers.  Maybe we're missing out on something great? [[User:Jeremy|(Jeremy)]]
*: The u-blox reference design calls for a 47pF 10% 0603 capacitor in series between the receiver and antenna.  I have no idea why this is useful but apparently it must be, because this technique is commonly seen on WiFi cards, video transmitters, modems, even R/C receivers.  Maybe we're missing out on something great? [[User:Jeremy|(Jeremy)]]
* Power plug
This is typically used as a DC block capacitor.  Many RF amplifier circuits either require DC on their output to be powered, or have stray DC on the output.  Also, many antennas are shorted at DC. The capacitor serves as a high-pass filter that allows minimal loss at RF frequenciesIt isn't necessary unless the manufacturer specifies it.[[User:hpux735|(hpux735)]]
*: Most users agree that the 1.25mm Molex is inadequate for the 8-16V / 1-2A main power inputThe obsolete ''Lite'' board used a 4-pin 1.25mm molex to address this issue but it was akward to connect two pairs of tiny 26AWG wire to the large main-power wires. ''Tiny 0.9'' used a "Futaba/Hitec" style header for battery input - the idea was that you could simply modify your ESC moving the 5V wire over to the battery input terminal. This solution occupied a lot of space on the Tiny and the modified ESC could easily end up mistakenly connected to standard r/c equipment. Tiny 2.0 is currently slated to have large solder pads on the input capacitors that users can solder their own wires to. Please post suggestions for a "better" method, if one exists.
 
* Filtering for GPS antenna
: Make some sort of low pass or band pass filter to reject outside frequency's. This would be useful since most UAV's are not just used to fly but for video or other sorts of communication which tend to interfere with the GPS Signal. Maybe similar to some of these designs http://www.webx.dk/rc/video-wireless/filtergps.htm [[User:Danstah|(Danstah)]]
Re:
I have since found out that the lea-4p has a built in saw tooth filter. Adding a filter would probably only reduce the signal strength
 
 
* VIRTUAL AUTOPILOT (The Next Logical Step)*
 
The virtual autopilot concept is based on virtualizing the autopilot through the Paparazzi GCS software and meant for larger aerial platforms. The avionics unit will be an actual micro pc running Linux such as http://www.fit-pc.com/web/ or the gumstick. The altimeter, gyro, servos, sensors, cameras, custom I/O , etc... are all modular. The telemetry/datalink is a remote desktop connection to the pc on the remoted vehicle (remote vehicle has a hardware in the loop type configuration).
 
The modular design saves autopilot hardware development costs. The modular design also saves repair costs. For example, currently if sensors and other components become infused with the autopilot board and the board or sensor goes bad repair costs raises. A modular design with a virtualized autopilot creates an environment for rapid development and integration of anxilary equipment (sensors etc...). Hecto's Paparazzi software suite is perfectly designed for virtualizing an autopilot because its meant for autopilot development (I must add its ahead of its time!).
 
Think of all the hardware you can run through usb ports alone and all the programs you can run simultaneously on a pc. With a remote desktop connection through a TM link, your UAV increases its functionality significantly.
''
Akira Devereaux'' http://akiraproject.net/cv
 
[[Category:Autopilots]]

Latest revision as of 04:53, 25 January 2013

Proposed additions

We're always looking for great ideas. If you'd like to see something added or changed on Tiny v2.11 list it here! Please keep your suggestions relevant to this revision and post other requests in the Hardware Wish List.

  • Separate GPS Option
see TWOG/v1.0
  • EMI filters on ADC channels
    On Semiconductor NUF4220MNT1G 4-line EMI Filter
Analog sensors are severely affected by video and modem RF. We typically see ADC reading fluctuations of +/-0.5% in a well shielded installation, but a misbehaving video transmitter or a noisy Radiotronix modem can affect ADC channels by more than 50% in the same well shielded installation. The addition of effective filters to the ADC inputs should greatly reduce the effects of RFI and allow for a much broader range of RF equipment and airframe configurations.
I suggest the On Semiconductor NUF4220MNT1G. A 2mm x 2mm chip that filters 4 analog signals, attenuatiing RF frequencies above 16 Mhz but particularly the 800 Mhz to 5 Ghz range. (Jeremy)
NUF4220MN is a 4 line LC EMI filter array designed for audio applications. It offers greater than -30 dB attenuation at frequencies from 800 MHz to 5.0 GHz, with no line loss. This part is a single chip solution for audio interface applications, 2 speaker lines with a microphone line. This device also offers ESD protection-clamping transients from static discharges and ESD protection is provided across all capacitors.
  • Decoupling capacitor on GPS antenna
    The u-blox reference design calls for a 47pF 10% 0603 capacitor in series between the receiver and antenna. I have no idea why this is useful but apparently it must be, because this technique is commonly seen on WiFi cards, video transmitters, modems, even R/C receivers. Maybe we're missing out on something great? (Jeremy)

This is typically used as a DC block capacitor. Many RF amplifier circuits either require DC on their output to be powered, or have stray DC on the output. Also, many antennas are shorted at DC. The capacitor serves as a high-pass filter that allows minimal loss at RF frequencies. It isn't necessary unless the manufacturer specifies it.(hpux735)

  • Filtering for GPS antenna
Make some sort of low pass or band pass filter to reject outside frequency's. This would be useful since most UAV's are not just used to fly but for video or other sorts of communication which tend to interfere with the GPS Signal. Maybe similar to some of these designs http://www.webx.dk/rc/video-wireless/filtergps.htm (Danstah)

Re: I have since found out that the lea-4p has a built in saw tooth filter. Adding a filter would probably only reduce the signal strength


  • VIRTUAL AUTOPILOT (The Next Logical Step)*

The virtual autopilot concept is based on virtualizing the autopilot through the Paparazzi GCS software and meant for larger aerial platforms. The avionics unit will be an actual micro pc running Linux such as http://www.fit-pc.com/web/ or the gumstick. The altimeter, gyro, servos, sensors, cameras, custom I/O , etc... are all modular. The telemetry/datalink is a remote desktop connection to the pc on the remoted vehicle (remote vehicle has a hardware in the loop type configuration).

The modular design saves autopilot hardware development costs. The modular design also saves repair costs. For example, currently if sensors and other components become infused with the autopilot board and the board or sensor goes bad repair costs raises. A modular design with a virtualized autopilot creates an environment for rapid development and integration of anxilary equipment (sensors etc...). Hecto's Paparazzi software suite is perfectly designed for virtualizing an autopilot because its meant for autopilot development (I must add its ahead of its time!).

Think of all the hardware you can run through usb ports alone and all the programs you can run simultaneously on a pc. With a remote desktop connection through a TM link, your UAV increases its functionality significantly. Akira Devereaux http://akiraproject.net/cv