X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=TeleMetrum%2Findex.mdwn;h=a98fcac5a2a07bbdcbcff8fc96f7cc8e1a00a59a;hb=415edfec216fb96e224120de746155cc652a4c1b;hp=6ebc768868baa191518043a2e3b63089db0c2fb3;hpb=6da0c7bbadd549fad309aceefa15bfad52cdbbef;p=web%2Faltusmetrum diff --git a/TeleMetrum/index.mdwn b/TeleMetrum/index.mdwn index 6ebc768..a98fcac 100644 --- a/TeleMetrum/index.mdwn +++ b/TeleMetrum/index.mdwn @@ -1,11 +1,18 @@ # TeleMetrum This is a recording dual-deploy altimeter for high power model rocketry -with integrated telemetry link. +with integrated GPS and telemetry link. - - - +These are photos of our current version, +which includes an integrated GPS receiver and patch antenna: + + + + +And this is a photo of our original board with serial port for off-board GPS, +without the big off-board 1000uF cap from the original ejection circuit: + + ## Motivation ## @@ -26,7 +33,9 @@ Another friend at the same conference showed us a board he was working on using a different part in the same TI series, that integrated a transceiver and CPU on the same chip. It didn't take us long to realize that with such a part we could combine and -simplify things by building a new altimeter with integrated RF link! +simplify things by building a new altimeter with integrated RF link! And +after gaining some experience in 2009 with a first version, we realized we +always want GPS on board, which lead to our current second generation boards. ## Features ## @@ -35,45 +44,70 @@ simplify things by building a new altimeter with integrated RF link! * Recording altimeter for model rocketry * Supports dual deployment (can fire 2 ejection charges) * 70cm ham-band transceiver for telemetry downlink -* Primary operations based on pressure sensor -* Temperature sensor +* Barometric pressure sensor good to 45k feet MSL * 1-axis high-g accelerometer for motor characterization +* On-board, integrated GPS receiver * On-board non-volatile memory for flight data storage -* Serial port for attachment of GPS module * USB for power, configuration, and data recovery * Integrated support for LiPo rechargeable batteries -* 2.5 x 1 inch board designed to fit inside 29mm airframe coupler tube +* Uses LiPo to fire e-matches, optional support for separate pyro battery +* 2.75 x 1 inch board designed to fit inside 29mm airframe coupler tube ### Developer View ### -* [TI CC1111F32](http://focus.ti.com/docs/prod/folders/print/cc1111f32.html) Low Power RF System-on-Chip - * Sub-1Ghz transceiver - * 8051 MCU - * 32k Flash - * 4k RAM - * USB 2.0 - * analog, digital, and serial I/O -* [Microchip 25LC1024](http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en520389) CMOS serial EEPROM - * 128k x 8 - * SPI interface -* Various Sensors +* Hardware Features + * [TI CC1111F32](http://focus.ti.com/docs/prod/folders/print/cc1111f32.html) Low Power RF System-on-Chip + * Sub-1Ghz transceiver + * 8051 MCU + * 32k Flash + * 4k RAM + * USB 2.0 + * 6 12-bit analog inputs (11 bits with single-ended sensors) + * 2 channels of serial I/O + * digital I/O + * [Atmel AT45DB081D](http://www.atmel.com/dyn/products/product_card.asp?part_id=3819) DataFlash memory + * 1M x 8 + * 256 byte page size + * SPI interface + * other parts in this Atmel DataFlash series can optionally be used + * [SkyTraq](http://www.skytraq.com.tw/) Venus634FLPx GPS receiver + * on-board passive patch antenna + * U.FL connector with 3.3V DC for optional external amplified antenna + * async serial interface * [Freescale MP3H6115A](http://www.freescale.com/webapp/search.partparamdetail.framework?PART_NUMBER=MP3H6115A6U) pressure sensor * [Freescale MMA2202EG](http://www.freescale.com/webapp/search.partparamdetail.framework?PART_NUMBER=MMA2202EG) 50g accelerometer. Can use 40-200g variants! - * [Microchip MCP9700A](http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en027103) temperature sensor -* Software Features (planned) +* Software Features * Written mostly in C with some 8051 assembler * Runs from on-chip flash, uses on-chip RAM, stores flight data to - serial EEPROM chip + serial DataFlash chip * USB serial emulation for "console" interface - * USB mass storage emulation for data recovery * Tools Used * [gEDA](http://www.gpleda.org/) for schematic capture and PCB layout * [SDCC](http://sdcc.sourceforge.net/) compiler and source debugger - * [FreeRTOS](http://www.freertos.org/) kernel * Licenses * The hardware is licensed under the [TAPR](http://www.tapr.org) [Open Hardware License](http://www.tapr.org/ohl.html) * The software is licensed [GPL version 2](http://www.gnu.org/licenses/old-licenses/gpl-2.0.html) +### v0.1 Differences ### + +* 2.5 x 1 inch board with all parts mounted on one side +* 4-pin PicoBlade serial port connector for attachment of external GPS module +* USB connector projected approximately 3mm over the edge of the board +* Debug connector used 4 IC socket pins on 100 mil centers +* no companion board interface +* [Microchip 25LC1024](http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en520389) CMOS serial EEPROM instead of DataFlash + * 128k x 8 + * SPI interface +* [Microchip MCP9700A](http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en027103) discrete temperature sensor + * eliminated in v0.2 to free GPIO line for companion interface +* used 1000uF electrolytic capacitor charged to 5V for pyro supply +* two LEDs instead of one attached to CPU + * eliminated second LED to free GPIO line for companion interface + +## [Production History](production) ## + +## [Flight Logs](flightlogs) ## + ## Problems ## * The CC1111F32 is a 36-pin QFN package, which necessitates reflow @@ -83,32 +117,67 @@ simplify things by building a new altimeter with integrated RF link! place parts! Without an inspection microscope, loading and testing these boards might be impossible. -* The v0.1 artwork has two issues that require cuts and jumps. The first is - that we need chip select on the SPI memory. To fix that, we give up the - ability to put the accelerometer into self-test mode and use that GPIO line - to pull chip select on the memory. The second is that the igniter sense - circuits each need a second resistor to complete the voltage divider so our - 3.3V CPU ADC can read the 5V ejection voltage. This is fixed by changing - two resistor values, and tacking two additional resistors onto the board - with jumpers to ground. +* The v0.1 artwork had three issues, two of which required physical rework + on each board. All of these issues were fixed in v0.2. + + * the USB connector footprint was placed wrong, so that the + connector hung out over the edge of the board instead of being + flush. + * we needed chip select on the SPI memory. To fix that, we gave up the + ability to put the accelerometer into self-test mode and used that + GPIO line to pull chip select on the memory, which required two + cuts and two jumpers. + * the igniter sense circuits each needed a second resistor to + complete the voltage divider so our 3.3V CPU ADC could read the + 5V ejection voltage. This was fixed by changing two resistor + values, and tacking two additional resistors onto the board + with jumpers to ground. ## Artifacts ## The hardware design current gEDA files are available from -[git.gag.com](http://git.gag.com). The 'fab' tag on the master branch reflects -the artwork as sent out for PCB fab. The 'loaded' tag on the master branch -indicates the parts Bdale loads for a functional board, but the schematic -does not reflect the cuts and jumps or added resistors. The 'nextcut' branch -is work towards our next PCB revision. The 'ground' branch has a cut-down -schematic used to generate the BOM for partially loading boards to use in -the matching TeleTerra ground station design. - -Keith has working data collection firmware, however the firmware is under a -massive, rapid rewrite to eliminate FreeRTOS which is much more generalized -and capable than we need... and consuming more system resources than we -can tolerate. As soon as we're over this transition, the sourcecode to the -firmware and related tools will also be made available. - -As of 11 April 2009, the first two boards are fully checked out, we have some -initial firmware capable of data logging ready, and as soon as we get a good -day to fly we hope to log our first flight data! +[git.gag.com](http://git.gag.com) in the project +[hw/telemetrum](http://git.gag.com/?p=hw/telemetrum;a=summary). + +Work on the next version proceeds on the master branch, with occasional +temporary branches created when Bdale is making some major / speculative +change. The 'v0.2' and 'v0.1' branches document what we're actually flying +right now on the two respective PCB revisions. The 'ground' branch has a +cut-down schematic used to generate the BOM for partially loading v0.1 boards +to used on the ground. We call the on-the-ground version 'TeleDongle'. + +For those who don't have ready access to the gEDA suite, here are pdf snapshots +of files in more easily readable form. + +* These are from the v0.2 branch: + * [schematic](v0.2/telemetrum.pdf) + * [pcb artwork](v0.2/telemetrum.pcb.pdf) + * [bill of materials](v0.2/partslist.csv) +* These are as of the working-v0.1 tag: + * [schematic](v0.1/telemetrum.pdf) + * [pcb artwork](v0.1/telemetrum.pcb.pdf) + * [bill of materials](v0.1/telemetrum.bom) + +Our [AltOS](../AltOS) firmware works well enough that we now routinely fly +TeleMetrum with no backup. Rockets with v0.1 boards have exceeded 50g +acceleration, been above Mach 1, and reached altitudes greater +than 12k feet AGL with great results. Keith's ground station program +called ao-view logs telemetry to disk, displays current and max values for +key parameters during flight, and even includes voice synthesis +during the flight so that our eyes can stay on the rockets! We have post +flight analysis software that makes it easy to extract data from the board, +analyze it, and even generate KML files for viewing flights in GoogleEarth! +More details on the software, including full source code and pre-built packages +can be found on the [AltOS](../AltOS) page on this site. + +## Future Plans ## + +As of early February 2010, three prototypes of v0.2 are done and working on +the bench. We hope to flight test them shortly, then arrange a production +run in time to make TeleMetrum available in assembled and tested form to +others in the rocketry hobby who have expressed interest in time for the +2010 flying season. + +Because we understand that not everyone uses Linux, we've started discussing +the best way to make a cross-platform ground station program for use with +[AltOS](../AltOS), perhaps in Java...