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).
11 For the latest TeleMetrum firmware and related ground station software, please
12 visit the [AltOS](../AltOS) page on this site.
14 These are photos of our current production version:
16 <a href="v1.1/telemetrum-v1.1-thside.jpg"> <img src="v1.1/telemetrum-v1.1-thside-thumb.jpg"></a>
17 <a href="v1.1/telemetrum-v1.1-smtside.jpg"> <img src="v1.1/telemetrum-v1.1-smtside-thumb.jpg"></a>
23 * Recording altimeter for model rocketry
24 * Supports dual deployment (can fire 2 ejection charges)
25 * 70cm ham-band transceiver for telemetry downlink
26 * Barometric pressure sensor good to 45k feet MSL
27 * 1-axis high-g accelerometer for motor characterization
28 * On-board, integrated GPS receiver
29 * On-board non-volatile memory for flight data storage
30 * USB for power, configuration, and data recovery
31 * Integrated support for LiPo rechargeable batteries
32 * Uses LiPo to fire e-matches, can be factory modified to support separate pyro battery
33 * 2.75 x 1 inch board designed to fit inside 29mm airframe coupler tube
35 ### Developer View ###
38 * [TI CC1111F32](http://focus.ti.com/docs/prod/folders/print/cc1111f32.html) Low Power RF System-on-Chip
39 * Sub-1Ghz transceiver
44 * 6 12-bit analog inputs (11 bits with single-ended sensors)
45 * 2 channels of serial I/O
47 * [Winbond W25Q16](http://www.winbond.com/NR/exeres/A3D21C82-A0B6-4586-A770-2F0883A805FF.htm) serial flash memory
50 * [SkyTraq](http://www.skytraq.com.tw/) Venus634FLPx GPS receiver
51 * on-board [Taoglas AP.17A.01](http://www.taoglas.com/antennas/GPS_Antennas/Internal_GPS_-_Active_Patch_Modules/)
52 single-stage active patch antenna
53 * U.FL connector with 3.3V DC can be re-purposed for optional external amplified antennas
54 * async serial interface
55 * [Freescale MP3H6115A](http://www.freescale.com/webapp/search.partparamdetail.framework?PART_NUMBER=MP3H6115A6U) pressure sensor
56 * [Freescale MMA2202EG](http://www.freescale.com/webapp/search.partparamdetail.framework?PART_NUMBER=MMA2202EG) 50g accelerometer. Can use 40-200g variants!
58 * Written mostly in C with some 8051 assembler
59 * Runs from on-chip flash, uses on-chip RAM, stores flight data to
61 * USB serial emulation for "console" interface
63 * [gEDA](http://www.gpleda.org/) for schematic capture and PCB layout
64 * [SDCC](http://sdcc.sourceforge.net/) compiler and source debugger
66 * The hardware is licensed under the [TAPR](http://www.tapr.org) [Open Hardware License](http://www.tapr.org/ohl.html)
67 * The software is licensed [GPL version 2](http://www.gnu.org/licenses/old-licenses/gpl-2.0.html)
69 ## [Production History](../production) ##
71 ## [Flight Logs](flightlogs) ##
75 There is a single manual for TeleMetrum and all other Altus Metrum products,
76 which is available in [html](../AltOS/doc/altusmetrum.html) and
77 [pdf](../AltOS/doc/altusmetrum.pdf) formats.
79 The hardware design current gEDA files are available from
80 [git.gag.com](http://git.gag.com) in the project
81 [hw/telemetrum](http://git.gag.com/?p=hw/telemetrum;a=summary).
83 Work on the next version proceeds on the master branch, with occasional
84 temporary branches created when Bdale is making some major / speculative
85 change. Branched with names like 'v0.2' document what we're actually flying
86 on the respective PCB revisions. The 'ground' branch has a cut-down schematic
87 used to generate the BOM for partially loading v0.1 boards to used on the
88 ground. We call the on-the-ground version '[TeleDongle](../TeleDongle)', and
89 newer versions have their own PCB design.
91 For those who don't have ready access to the gEDA suite, here are pdf snapshots
92 of the files for Production PCB version 1.0 in more easily readable form.
94 * [schematic](v1.1/telemetrum.pdf)
95 * [pcb artwork](v1.1/telemetrum.pcb.pdf)
96 * [bill of materials](v1.1/partslist.csv)
98 Rockets we know of flying with TeleMetrum boards have exceeded 50g acceleration,
99 been well above Mach 1, and reached altitudes
100 greater than 25k feet AGL with great results. Keith's second generation
101 ground station program called altosui works on Windows, Mac, and Linux systems
102 and logs telemetry to disk, displays current and max values for key parameters
103 during flight, includes voice synthesis during the flight so that
104 our eyes can stay on the rockets, and even includes live display of rocket
105 position over moving maps! After flight, altosui can extract the
106 complete flight log from TeleMetrum, can display plots of the data from either
107 the telemetry received by radio or the onboard flight log, can output a kml
108 file for use with [Google Earth](http://earth.google.com), and can also
109 output all the flight data as a csv file for easy import to spreadsheet
110 programs or other analysis tools allowing you to perform whatever
111 custom analysis you can envision! More details on the software,
112 including full source code and pre-built packages
113 can be found on the [AltOS](../AltOS) page on this site.
117 TeleMetrum v1.1 meets all of our expectations, except for one mis-placed
118 trace also present in v1.0. The error makes use of a separate pyro battery
119 less trivial than intended. We'll fix that for a future production run.
123 * The CC1111F32 is a 36-pin QFN package, which necessitates reflow
124 soldering. Since we needed to reflow solder anyway, and because TI used
125 them in their reference design, we went a little crazy and used 0402
126 passive parts everywhere. That means working under a microscope to
127 place parts! Without an inspection microscope, loading and testing these
128 boards might be impossible.
130 * The addition of on-board GPS in v0.2 means that the total power consumption
131 can exceed the rate at which we draw power from the USB interface,
132 particularly when the GPS is in cold start mode. This means a battery must
133 be attached during operation, and also that the battery will only charge
134 effectively from USB when the board is turned off.
140 These are photos of our third version, which was the basis of our first
141 production build. These were sold between April and December 2010, and
144 <a href="v1.0/cimg5972-crop.jpg"> <img src="v1.0/cimg5972-thumb.jpg"></a>
145 <a href="v1.0/cimg5974-crop.jpg"> <img src="v1.0/cimg5974-thumb.jpg"></a>
147 The differences between v1.0 and v1.1 were small:
149 * different flash memory part due to supplier availability problems
150 * updated reset circuit to improve reliability at temperature extremes
151 * changed the GPS antenna footprint to eliminate the large through-hole
152 originally intended for use with a passive patch
153 * irq line eliminated from the companion port
154 * an additional resistor divider added to allow sampling the 5V supply
156 The schematics and PCB artwork for this version are on the v1.0 branch in
157 our git repository, here are pdf copies for easy reference:
159 * [schematic](v1.0/telemetrum.pdf)
160 * [pcb artwork](v1.0/telemetrum.pcb.pdf)
161 * [bill of materials](v1.0/partslist.csv)
166 These are photos of our second version, which included the integrated Venus
167 GPS receiver, but with a passive patch antenna that turned out to have
168 disappointing performance due to our many PCB geometry constraints. It also
169 used a voltage regulator with less capacity which we felt was marginal for
170 supporting the companion boards we have planned:
172 <a href="v0.2/cimg5164-cropped.jpg"> <img src="v0.2/cimg5164-thumb.jpg"></a>
173 <a href="v0.2/cimg5171-cropped.jpg"> <img src="v0.2/cimg5171-thumb.jpg"></a>
175 Other than cleaning up the silkscreen, the differences between v0.2 and
176 v1.0 boards were really quite small:
178 * 100ma LDO regulator instead of the current 150ma part
180 * different value for C36 reset capacitor
182 The schematics and PCB artwork for this version are on the v0.2 branch in
183 our git repository, here are pdf copies for easy reference:
185 * [schematic](v0.2/telemetrum.pdf)
186 * [pcb artwork](v0.2/telemetrum.pcb.pdf)
187 * [bill of materials](v0.2/partslist.csv)
191 And this is a photo of our original board with serial port for off-board GPS,
192 without the big off-board 1000uF cap from the original ejection circuit:
194 <a href="v0.1/loadedpair.jpg"> <img src="v0.1/loadedpair-thumb.jpg"></a>
196 The differences between v0.1 and later boards were substantial:
198 * 2.5 x 1 inch board with all parts mounted on one side
199 * 4-pin PicoBlade serial port connector for attachment of external GPS module
200 * USB connector projected approximately 3mm over the edge of the board
201 * Debug connector used 4 IC socket pins on 100 mil centers
202 * no companion board interface
203 * 50ma LDO regulator on early boards, later boards used a 100ma part
204 * [Microchip 25LC1024](http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en520389) CMOS serial EEPROM instead of DataFlash
207 * [Microchip MCP9700A](http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en027103) discrete temperature sensor
208 * used 1000uF electrolytic capacitor charged to 5V for pyro supply
209 * two LEDs instead of one attached to CPU
211 The elimination of the discrete temperature sensor and second LED were
212 necessary to support the companion board interface added in v0.2.
214 The v0.1 artwork had three issues, two of which required physical rework
215 on each board. All of these issues were fixed in v0.2.
217 * The USB connector footprint was placed wrong, so that the
218 connector hung out over the edge of the board instead of being
220 * We needed chip select on the SPI memory. To fix that, we gave up the
221 ability to put the accelerometer into self-test mode and used that
222 GPIO line to pull chip select on the memory, which required two
223 cuts and two jumpers.
224 * The igniter sense circuits each needed a second resistor to
225 complete the voltage divider so our 3.3V CPU ADC could read the
226 5V ejection voltage. This was fixed by changing two resistor
227 values, and tacking two additional resistors onto the board
228 with jumpers to ground.
230 The schematics and PCB artwork for this version as of the working-v0.1 tag
231 are available here are pdf copies for easy reference:
233 * [schematic](v0.1/telemetrum.pdf)
234 * [pcb artwork](v0.1/telemetrum.pcb.pdf)
235 * [bill of materials](v0.1/telemetrum.bom)