input/blog/2016/2016_11_05_frsky_telemetry.md

@@ -16,11 +16,11 @@ To output the telemetry data, the FrSky transmitter module has an RS232 serial p
 
 To display the received data with the Arduino, I'm using [this cheap I2C OLED display from HobbyKing](https://www.hobbyking.com/en_us/multiwii-oled-display-module-i2c-128x64-dot-mwc.html).
 
-<div class="lightgallery">
-    <a href="https://i.imgur.com/4W3O9zr.png">
-        <img src="https://i.imgur.com/pa8UJW8.png" alt="Schematic">
-    </a>
-</div>
+<!--%
+lightgallery([
+    [ "img/arduino_frsky_telemetry_1.png", "Schematic" ]
+])
+%-->
 
 The FrSky telemetry protocol transmits two ADC values and a serial data stream. Currently, the received serial user data is simply displayed but not used further. One of the two ADC values can be converted to a voltage using a simple algorithm: Just apply two different (known) voltages to the ADC input and note the ADC output value received (it's displayed on the OLED). Then enter these two voltage-value datapairs in to the `options.h` file and all intermediate values will be interpolated. For example:
 
@@ -39,17 +39,13 @@ The FrSky telemetry protocol transmits two ADC values and a serial data stream.
 
 This means, for Model 1 a value of 231 equals 3.88V, and for Model 2 a value of 169 means 9.00V. As you can see, multiple models with different voltage dividers and battery ranges can be used this way, and each one can have individual alarms set.
 
-<div class="lightgallery">
-    <a href="http://i.imgur.com/U6wNsI4.jpg">
-        <img src="http://i.imgur.com/Uuro1FN.png" alt="Photo 1">
-    </a>
-    <a href="http://i.imgur.com/cExsBPu.jpg">
-        <img src="http://i.imgur.com/MOI2jv5.png" alt="Photo 2">
-    </a>
-    <a href="http://i.imgur.com/C18T33u.jpg">
-        <img src="http://i.imgur.com/ve6bCwT.png" alt="Photo 3">
-    </a>
-</div>
+<!--%
+lightgallery([
+    [ "img/arduino_frsky_telemetry_2.jpg", "Photo 1" ],
+    [ "img/arduino_frsky_telemetry_3.jpg", "Photo 2" ],
+    [ "img/arduino_frsky_telemetry_4.jpg", "Photo 3" ]
+])
+%-->
 
 I've used an Arduino Pro Mini and could easily fit it, the OLED, beeper, switched and LED into my existing RC transmitter. The sketch should run without changes on any Arduino based on the Atmega328.
 

input/projects/3d-printing/bed-leveling-util.md

@@ -8,7 +8,7 @@ date: 2016-06-07
 update: 2016-06-12
 ---
 
-<span class="listdesc">[...back to 3D-Printing overview](3d-printing.html)</span>
+<!--% backToParent() %-->
 
 This is a manual Mesh Bed Leveling GUI utility for 3D printers with Marlin Firmware.
 

input/projects/3d-printing/ctc-i3.md

@@ -5,7 +5,7 @@ position: 20
 comments: true
 ---
 
-<span class="listdesc">[...back to 3D-Printing overview](3d-printing.html)</span>
+<!--% backToParent() %-->
 
 The CTC i3 Pro B is a very cheap chinese Prusa i3 clone.
 I bought it a couple of years ago for about 110 Euros.

input/projects/3d-printing/fabrikator-mini.md

@@ -5,9 +5,7 @@ position: 10
 comments: true
 ---
 
-<span class="listdesc">[...back to 3D-Printing overview](3d-printing.html)</span>
-
-**More content coming soon!**
+<!--% backToParent() %-->
 
 I bought the [Fabrikator Mini V1.5 from HobbyKing](https://hobbyking.com/en_us/fabrikator-mini-3d-printer-transparent-eu-230v-v1-5.html) in about March 2016.
 So that's pretty much exactly three and a half years ago, at the time of this writing.

input/projects/3d-printing/ikea-lack.md

@@ -5,7 +5,7 @@ position: 30
 comments: true
 ---
 
-<span class="listdesc">[...back to 3D-Printing overview](3d-printing.html)</span>
+<!--% backToParent() %-->
 
 As is common in the 3D printing community, I have built myself a tower of Ikea Lack tables to store my printers in.
 It has three levels.

input/projects/3d-printing/octoprint.md

@@ -5,7 +5,7 @@ position: 40
 comments: true
 ---
 
-<span class="listdesc">[...back to 3D-Printing overview](3d-printing.html)</span>
+<!--% backToParent() %-->
 
 All my 3D printers are connected to a Raspberry Pi running [OctoPrint](https://octoprint.org/).
 For ease of use, I suggest downloading and installing a pre-made [OctoPi image](https://octoprint.org/download/).

input/projects/3d-printing/octotray.md

@@ -8,7 +8,7 @@ date: 2021-05-08
 update: 2021-05-13
 ---
 
-<span class="listdesc">[...back to 3D-Printing overview](3d-printing.html)</span>
+<!--% backToParent() %-->
 
 To quickly print new stuff on one of my printers, I am using the [OctoPrint](https://octoprint.org) integration of [PrusaSlicer](https://github.com/prusa3d/PrusaSlicer).
 Unfortunately, it does not allow me to turn on the printers power supply using the Raspberry Pi.

input/projects/quadcopters/aurora100.md

@@ -3,10 +3,9 @@ description: 3S LiPo, 100mm frame, 1104 6500KV motors
 parent: quadcopters
 position: 20
 date: 2017-07-17
-update: 2021-05-21
 ---
 
-<span class="listdesc">[...back to RC-Vehicles overview](quadcopters.html)</span>
+<!--% backToParent() %-->
 
 Not being totally happy with the power available with [my 2S xyAurora90](aurora90.html) I decided to build a 3S Aurora100 in July 2017.
 

input/projects/quadcopters/aurora90.md

@@ -3,10 +3,9 @@ description: 2S LiPo, 90mm frame, 1103 8000KV motors
 parent: quadcopters
 position: 30
 date: 2017-03-07
-update: 2021-05-21
 ---
 
-<span class="listdesc">[...back to RC-Vehicles overview](quadcopters.html)</span>
+<!--% backToParent() %-->
 
 The build started at the end of January 2017 and it was my main copter for flights indoors and outside in the garden for a long time.
 

input/projects/quadcopters/lx5.md

@@ -3,10 +3,9 @@ description: 4S LiPo, 220mm frame, 2205 2300KV motors
 parent: quadcopters
 position: 10
 date: 2017-11-01
-update: 2021-05-21
 ---
 
-<span class="listdesc">[...back to RC-Vehicles overview](quadcopters.html)</span>
+<!--% backToParent() %-->
 
 At the end of 2017 I had to give in to the urge of building a bigger more powerful copter.
 After my first failed attempts with large copters, gaining some experience with smaller frames seemed useful.

input/projects/quadcopters/trifecta.md

@@ -0,0 +1,84 @@
+title: Tricopter
+description: 3S LiPo, Quanum Trifecta frame, 2204 2300KV motors
+parent: quadcopters
+position: 60
+date: 2016-05-25
+---
+
+<!--% backToParent() %-->
+
+As a second attempt for a self-built copter I decided to try and build a Tricopter.
+These only have three motors, with the third degree of freedom (yaw) being provided by tilting the back rotor using a servo.
+
+<!--%
+lightgallery([
+    [ "img/trifecta_photo_1.jpg", "Top view" ],
+    [ "img/trifecta_photo_2.jpg", "Front view" ],
+    [ "img/trifecta_photo_4.jpg", "Top back right view" ],
+    [ "img/trifecta_photo_3.jpg", "Top back left view" ],
+    [ "img/trifecta_photo_5.jpg", "Yaw mechanism tilted" ],
+    [ "img/trifecta_photo_8.jpg", "Folded up, side view" ]
+])
+%-->
+
+Here are some recordings of the FPV footage.
+Be aware that these videos are recorded from the received signal on the ground.
+Not only can you see lots of interference and other HF problems, the loss of quality from the video recorder and the YouTube encoding is also very noticeable.
+In real-life, the picture doesn't look *that* bad.
+
+<!--%
+lightgallery([
+    [ "https://www.youtube.com/watch?v=OyqBxzw04xs", "img/xytrifecta_crash_yaw_thumb.jpg", "Quanum Trifecta Crash Yaw Mechanism"],
+    [ "https://www.youtube.com/watch?v=e11Yb5sWEGo", "img/xytrifecta_crash_thumb.jpg", "Quanum Trifecta mysterious crash" ]
+])
+%-->
+
+I quite like the Trifecta frame.
+It can be folded down considerably for easier transportation and storage, while still being surprisingly sturdy.
+
+You need to use a relatively small battery, otherwise the copter is too high up, the back foot not reaching the ground, balancing on the battery.
+I printed a longer foot because of that.
+
+I had some problems with the first servo I tried, but after switching to the metal gear servo listed below, the yaw mechanism has worked perfectly.
+
+## Parts List
+
+The prices listed below are just what I found while doing this page some years later, not the real prices I paid back then.
+
+<!--%
+tableHelper([ "align-right", "align-last-right", "align-right"],
+    [ "Part", "Description", "Cost" ], [
+        [ "Frame", ("Quanum Trifecta Mini Foldable Tricopter Frame", "https://hobbyking.com/en_us/quanum-trifecta-mini-foldable-tricopter-frame-kit.html"), "27.67€" ],
+        [ "Servo", ("Emax ES09MD Digital Metallgetriebe Mini Servo", "https://www.premium-modellbau.de/emax-es09md-digital-metallgetriebe-mini-servo-15g-0-08s-2-6kg-kugellager-es08md"), "12.90€" ],
+        [ "FC", ("AfroFlight Naze32 Rev6 Flight Controller (Acro)", "https://hobbyking.com/en_us/afroflight-naze32-rev6-flight-controller-acro.html"), "23.06€" ],
+        [ "ESCs", ("3x ZTW Spider Series 18A OPTO Multi-Rotor ESC 2~4S (BLHeli/SimonK Firmware)", "https://hobbyking.com/de_de/ztw-spider-series-18a-opto-multi-rotor-esc-2-4s-blheli-simonk-firmware.html"), "24.99€" ],
+        [ "Motors CW", ("2x Multistar Elite 2204-2300KV Multi-Rotor Motor 3-4S (CW Prop Adapter)", "https://hobbyking.com/en_us/multistar-elite-2204-2300kv-multi-rotor-motor-cw-prop-adapter.html"), "23.90€" ],
+        [ "Motors CCW", ("1x Multistar Elite 2204-2300KV Multi-Rotor Motor 3-4S (CCW Prop Adapter)", "https://hobbyking.com/en_us/multistar-elite-2204-2300kv-multi-rotor-motor-ccw-prop-adapter.html"), "12.45€" ],
+        [ "Props", ("10 Pairs LDARC 5x4.5x3 5045 5 Inch 3-Blade Propeller CW CCW", "https://www.banggood.com/10-Pairs-LDARC-5x4_5x3-5045-5-Inch-3-Blade-Propeller-CW-CCW-for-RC-FPV-Racing-Drone-p-1067877.html?cur_warehouse=CN&ID=223"), "6.95€" ],
+        [ "Cam", ("Sony 700TVL PAL FPV Camera", "https://amzn.to/3i0cUh8"), "15.00€" ],
+        [ "VTx", ("SkyZone TS5823 5.8GHz 32CH A/V 200mW Mini FPV Transmitter", "https://hobbyking.com/en_us/skyzone-ts5823-5-8ghz-32ch-a-v-200mw-mini-fpv-transmitter-v2.html"), "17.12€" ],
+        [ "OSD", ("Minim OSD v1.1", "https://hobbyking.com/en_us/minim-osd-v1-1.html"), "19.79€" ],
+        [ "Rx", ("FrSky D8R-XP 2.4Ghz Receiver (w/telemetry & CPPM)", "https://hobbyking.com/en_us/frsky-d8r-xp-2-4ghz-receiver-w-telemetry-cppm.html"), "25.66€" ],
+        [ "Battery", ("Turnigy 1400mAh 3S 40C Lipo Pack w/XT60", "https://hobbyking.com/en_us/turnigy-1400mah-3s-40c-lipo-pack-w-xt60.html?queryID=&objectID=78388"), "13.42€" ],
+        [ "OLED", ("128x64 I2C OLED", "https://amzn.to/3usYHMi"), "9.99€" ],
+        [ "", "Sum", "232.90€" ]
+    ]
+)
+%-->
+
+Here are some more photos.
+
+<!--%
+lightgallery([
+    [ "img/trifecta_photo_6.jpg", "Folded up, back view" ],
+    [ "img/trifecta_photo_7.jpg", "Folded up, front view" ],
+    [ "img/quanum_trifecta_1.jpg", "Front view with Xiaomi Yi" ],
+    [ "img/quanum_trifecta_6.jpg", "3D printed electronics mount on top" ],
+    [ "img/quanum_trifecta_4.jpg", "3D printed longer back leg, on copter" ],
+    [ "img/quanum_trifecta_5.jpg", "3D printed longer back leg" ],
+    [ "img/quanum_trifecta_7.jpg", "3D printed electronics mount" ],
+    [ "img/quanum_trifecta_8.jpg", "Copter closed up" ],
+    [ "img/quanum_trifecta_2.jpg", "Xiaomi Yi 3D printed holder" ],
+    [ "img/quanum_trifecta_3.jpg", "Poorly 3D printed camera holder" ]
+])
+%-->

macros.py

@@ -12,6 +12,17 @@ DEFAULT_LANG = "en"
 BASE_URL = "https://www.xythobuz.de"
 
 # -----------------------------------------------------------------------------
+# sub page helper macro
+# -----------------------------------------------------------------------------
+
+def backToParent():
+    url = page.get("parent", "") + ".html"
+    posts = [p for p in pages if p.url == url]
+    if len(posts) > 0:
+        p = posts[0]
+        print '<span class="listdesc">[...back to ' + p.title + ' overview](' + p.url + ')</span>'
+
+# -----------------------------------------------------------------------------
 # table helper macro
 # -----------------------------------------------------------------------------