3 This is a recording dual-deploy altimeter for high power model rocketry
4 with integrated GPS and telemetry link.
6 Production units are available from the
7 [Garbee and Garbee](http://auric.gag.com) web
8 store. TeleMetrum starter kits are also now available from
9 [Apogee Components](http://www.apogeerockets.com/Altus_Metrum_GPS.asp)
10 and [Australian Rocketry](http://ausrocketry.com.au/).
12 For the latest TeleMetrum firmware and related ground station software, please
13 visit the [AltOS](../AltOS) page on this site.
15 These are photos of our current production version:
17 <a href="v1.1/telemetrum-v1.1-thside.jpg"> <img src="v1.1/telemetrum-v1.1-thside-thumb.jpg"></a>
18 <a href="v1.1/telemetrum-v1.1-smtside.jpg"> <img src="v1.1/telemetrum-v1.1-smtside-thumb.jpg"></a>
24 * Recording altimeter for model rocketry
25 * Supports dual deployment (can fire 2 ejection charges)
26 * 70cm ham-band transceiver for telemetry downlink
27 * Barometric pressure sensor good to 45k feet MSL
28 * 1-axis high-g accelerometer for motor characterization
29 * On-board, integrated GPS receiver
30 * On-board non-volatile memory for flight data storage
31 * USB for power, configuration, and data recovery
32 * Integrated support for LiPo rechargeable batteries
33 * Uses LiPo to fire e-matches, can be factory modified to support separate pyro battery
34 * 2.75 x 1 inch board designed to fit inside 29mm airframe coupler tube
36 ### Developer View ###
39 * [TI CC1111F32](http://focus.ti.com/docs/prod/folders/print/cc1111f32.html) Low Power RF System-on-Chip
40 * Sub-1Ghz transceiver
45 * 6 12-bit analog inputs (11 bits with single-ended sensors)
46 * 2 channels of serial I/O
48 * [Winbond W25Q16](http://www.winbond.com/NR/exeres/A3D21C82-A0B6-4586-A770-2F0883A805FF.htm) serial flash memory
51 * [SkyTraq](http://www.skytraq.com.tw/) Venus634FLPx GPS receiver
52 * on-board [Taoglas AP.17A.01](http://www.taoglas.com/antennas/GPS_Antennas/Internal_GPS_-_Active_Patch_Modules/)
53 single-stage active patch antenna
54 * U.FL connector with 3.3V DC can be re-purposed for optional external amplified antennas
55 * async serial interface
56 * [Freescale MP3H6115A](http://www.freescale.com/webapp/search.partparamdetail.framework?PART_NUMBER=MP3H6115A6U) pressure sensor
57 * [Freescale MMA2202EG](http://www.freescale.com/webapp/search.partparamdetail.framework?PART_NUMBER=MMA2202EG) 50g accelerometer. Can use 40-200g variants!
59 * Written mostly in C with some 8051 assembler
60 * Runs from on-chip flash, uses on-chip RAM, stores flight data to
62 * USB serial emulation for "console" interface
64 * [gEDA](http://www.gpleda.org/) for schematic capture and PCB layout
65 * [SDCC](http://sdcc.sourceforge.net/) compiler and source debugger
67 * The hardware is licensed under the [TAPR](http://www.tapr.org) [Open Hardware License](http://www.tapr.org/ohl.html)
68 * The software is licensed [GPL version 2](http://www.gnu.org/licenses/old-licenses/gpl-2.0.html)
70 ## [Production History](../production) ##
72 ## [Flight Logs](flightlogs) ##
76 There is a single manual for TeleMetrum and all other Altus Metrum products,
77 which is available in [html](../AltOS/doc/altusmetrum.html) and
78 [pdf](../AltOS/doc/altusmetrum.pdf) formats.
80 The hardware design current gEDA files are available from
81 [git.gag.com](http://git.gag.com) in the project
82 [hw/telemetrum](http://git.gag.com/?p=hw/telemetrum;a=summary).
84 Work on the next version proceeds on the master branch, with occasional
85 temporary branches created when Bdale is making some major / speculative
86 change. Branched with names like 'v0.2' document what we're actually flying
87 on the respective PCB revisions. The 'ground' branch has a cut-down schematic
88 used to generate the BOM for partially loading v0.1 boards to used on the
89 ground. We call the on-the-ground version '[TeleDongle](../TeleDongle)', and
90 newer versions have their own PCB design.
92 For those who don't have ready access to the gEDA suite, here are pdf snapshots
93 of the files for Production PCB version 1.1 in more easily readable form.
95 * [schematic](v1.1/telemetrum.pdf)
96 * [pcb artwork](v1.1/telemetrum.pcb.pdf)
97 * [bill of materials](v1.1/partslist.csv)
99 Rockets we know of flying with TeleMetrum boards have exceeded 50g acceleration,
100 been well above Mach 1, and reached altitudes
101 greater than 25k feet AGL with great results. Keith's second generation
102 ground station program called AltosUI works on Windows, Mac, and Linux systems
103 and logs telemetry to disk, displays current and max values for key parameters
104 during flight, includes voice synthesis during the flight so that
105 our eyes can stay on the rockets, and even includes live display of rocket
106 position over moving maps! After flight, altosui can extract the
107 complete flight log from TeleMetrum, can display plots of the data from either
108 the telemetry received by radio or the onboard flight log, can output a kml
109 file for use with [Google Earth](http://earth.google.com), and can also
110 output all the flight data as a csv file for easy import to spreadsheet
111 programs or other analysis tools allowing you to perform whatever
112 custom analysis you can envision! More details on the software,
113 including full source code and pre-built packages
114 can be found on the [AltOS](../AltOS) page on this site. Feel free to
115 download the software and try it before purchasing our hardware!
119 TeleMetrum v1.1 meets all of our expectations, except for one mis-placed
120 trace also present in v1.0. The error makes use of a separate pyro battery
121 less trivial than intended. We'll fix that for a future production run.
125 * The CC1111F32 is a 36-pin QFN package, which necessitates reflow
126 soldering. Since we needed to reflow solder anyway, and because TI used
127 them in their reference design, we went a little crazy and used 0402
128 passive parts everywhere. That means working under a microscope to
129 place parts! Without an inspection microscope, loading and testing these
130 boards might be impossible.
132 * The addition of on-board GPS in v0.2 and later boards means that the total
134 can exceed the rate at which we draw power from the USB interface,
135 particularly when the GPS is in cold start mode. This means a battery must
136 be attached during operation, and also that the battery will only charge
137 effectively from USB when the board is turned off.
143 These are photos of our third version, which was the basis of our first
144 production build. These were sold between April and December 2010, and
147 <a href="v1.0/cimg5972-crop.jpg"> <img src="v1.0/cimg5972-thumb.jpg"></a>
148 <a href="v1.0/cimg5974-crop.jpg"> <img src="v1.0/cimg5974-thumb.jpg"></a>
150 The differences between v1.0 and v1.1 were small:
152 * different flash memory part due to supplier availability problems
153 * updated reset circuit to improve reliability at temperature extremes
154 * changed the GPS antenna footprint to eliminate the large through-hole
155 originally intended for use with a passive patch
156 * irq line eliminated from the companion port
157 * an additional resistor divider added to allow sampling the 5V supply
159 The schematics and PCB artwork for this version are on the v1.0 branch in
160 our git repository, here are pdf copies for easy reference:
162 * [schematic](v1.0/telemetrum.pdf)
163 * [pcb artwork](v1.0/telemetrum.pcb.pdf)
164 * [bill of materials](v1.0/partslist.csv)
169 These are photos of our second version, which included the integrated Venus
170 GPS receiver, but with a passive patch antenna that turned out to have
171 disappointing performance due to our many PCB geometry constraints. It also
172 used a voltage regulator with less capacity which we felt was marginal for
173 supporting the companion boards we have planned:
175 <a href="v0.2/cimg5164-cropped.jpg"> <img src="v0.2/cimg5164-thumb.jpg"></a>
176 <a href="v0.2/cimg5171-cropped.jpg"> <img src="v0.2/cimg5171-thumb.jpg"></a>
178 Other than cleaning up the silkscreen, the differences between v0.2 and
179 v1.0 boards were really quite small:
181 * 100ma LDO regulator instead of the current 150ma part
183 * different value for C36 reset capacitor
185 The schematics and PCB artwork for this version are on the v0.2 branch in
186 our git repository, here are pdf copies for easy reference:
188 * [schematic](v0.2/telemetrum.pdf)
189 * [pcb artwork](v0.2/telemetrum.pcb.pdf)
190 * [bill of materials](v0.2/partslist.csv)
194 And this is a photo of our original board with serial port for off-board GPS,
195 without the big off-board 1000uF cap from the original ejection circuit:
197 <a href="v0.1/loadedpair.jpg"> <img src="v0.1/loadedpair-thumb.jpg"></a>
199 The differences between v0.1 and later boards were substantial:
201 * 2.5 x 1 inch board with all parts mounted on one side
202 * 4-pin PicoBlade serial port connector for attachment of external GPS module
203 * USB connector projected approximately 3mm over the edge of the board
204 * Debug connector used 4 IC socket pins on 100 mil centers
205 * no companion board interface
206 * 50ma LDO regulator on early boards, later boards used a 100ma part
207 * [Microchip 25LC1024](http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en520389) CMOS serial EEPROM instead of DataFlash
210 * [Microchip MCP9700A](http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en027103) discrete temperature sensor
211 * used 1000uF electrolytic capacitor charged to 5V for pyro supply
212 * two LEDs instead of one attached to CPU
214 The elimination of the discrete temperature sensor and second LED were
215 necessary to support the companion board interface added in v0.2.
217 The v0.1 artwork had three issues, two of which required physical rework
218 on each board. All of these issues were fixed in v0.2.
220 * The USB connector footprint was placed wrong, so that the
221 connector hung out over the edge of the board instead of being
223 * We needed chip select on the SPI memory. To fix that, we gave up the
224 ability to put the accelerometer into self-test mode and used that
225 GPIO line to pull chip select on the memory, which required two
226 cuts and two jumpers.
227 * The igniter sense circuits each needed a second resistor to
228 complete the voltage divider so our 3.3V CPU ADC could read the
229 5V ejection voltage. This was fixed by changing two resistor
230 values, and tacking two additional resistors onto the board
231 with jumpers to ground.
233 The schematics and PCB artwork for this version as of the working-v0.1 tag
234 are available here are pdf copies for easy reference:
236 * [schematic](v0.1/telemetrum.pdf)
237 * [pcb artwork](v0.1/telemetrum.pcb.pdf)
238 * [bill of materials](v0.1/telemetrum.bom)