Honda motorcycle OBD/k-line interface gear indicator

I’m building a gear indicator and information display for my CBR500R. It uses an Arduino Pro Mini, Nokia 5110 display, and hooks in to the Honda diagnostic connector under the seat. Protocol is a custom OBD k-line format. Here is some useful information on the protocol used.

The first version I created used 2N7000 MOSFET’s for the serial interface and it worked fine on a breadboard. However, before I could build the final physical version I received some LIN transceivers that should simplify the circuit considerably. I’m working on a new version of the hardware design now.

Posted in Projects | Tagged , , | Leave a comment

Motorcycle Stand

I used FreeCAD to model this simple motorcycle stand before building it. It’s made out of 2×4’s with glue and screws. I think it could easily hold a whole car up.

Posted in Projects | Leave a comment

FemtoWii

This is a small 25mm by 30mm MultiWii board I started designing a while ago. I haven’t had much time to refine or test it. I did create a prototype board but that’s about it. The intent was to create a board small enough to be used on micro quads, helicopters, and planes.

I’m providing the KiCad schematic and board layout here.

Posted in Projects | Tagged , , | Leave a comment

FrSky Taranis

The radio doesn’t sit flat on the bottom when you set it down on a level surface.

External TX module pins must be bent to fit modules.

Posted in Projects | Tagged , , , | Leave a comment

Blade 130X

Project 130X.

Had a Rakon DFC CNC head that was not square from the factory so I pounded on it with a hammer to make it straight. 

:)

It appears to be possible to use an S107 tail motor to repair/replace the 130x servo motor.  The S107 motor is 4mm and the servo motor is normally 5mm so there is some extra space.  I used a piece of 1.5mm carbon rod to take up the extra space and it seems to work fine.  I may try to find some other method of holding the motor in place.  Also, rumour is that some S107 clones have 5mm tail motors.

Posted in Projects | Tagged , , | Leave a comment

mCPX

Bought a cheap mCPX off eBay that had a broken 3-in-1.  Fixed the 3-in-1 and converted to brushless using C05XL and super-FET XP-3A (double FET’s).

Main motor PWM signal (from resistor on back of board) is 1kHz.  On the 9x using OrangeRX TX module throttle ranges from -72% (completely off) to +72% (solid full throttle signal).

Posted in Projects | Tagged , , | Leave a comment

HiSKY for 9x

Transmitter project for the HiSKY protocol used with things like the WLToys V922

Posted in Projects | Tagged , , | Leave a comment

V922

See also my HiSKY/HT8 for 9x thread.

Attached is my ER9x model for the V922.  I have the HT8 set for Futaba mode.  Note this model has no “beginner” mode or even idle-down (ie. full 3D always).  To fly start with the F.MODE switch all the way up (ID0), move pitch/throttle to mid-stick, then switch F.MODE down one click to “1”.  It will spin up to full throttle within a few seconds.  The throttle cut switch works but what I do is just flick the F.MODE switch all the way up, this is much faster than reaching for the throttle cut.

These are the settings used in the model:


PPM6CH400uSec
PPM FrLen16.5mSec
PPM Shift SelNEG
ELE DirectionINV
AIL DirectionINV
Swash Type120
Swash Ring100
ELE EXPO0%D/R47%
AIL EXPO0%D/R60%
CH1CYC150%
CH2CYC250%
CH3Throttle
CH4Rudder
CH6CYC350%
LIMIT CH3INV
LIMIT CH4INV
Throttleflat 100%
Pitch± 68%

WLToys V922 tuning 3D

I have converted to brushless using the HK 14000kv motor and a modified HK XP-3A ESC that has new double-stacked FET’s.  I’m using Hyperion 550 mAh batteries for about 6:30 minutes flight time.

I measured the PWM signal on the main motor FET gate. It appears to have an 80us cycle time which means 12.5 kHz signal. With a 9x/HT8 the PWM signal starts minimum throttle (18% duty cycle) at approximately -52% and is full throttle at around 39%. These are only approximate because of calibration and PPM timing differences between radios.

Attached to this thread is a custom version of BLHeli specifically built for the V922.  BLHeli normally only supports a maximum of 8kHz PWM on its signal wire but the V922 motor output runs at 12.5kHz.  What this does is make the throttle skip from 66% to 100% with no way to use any value in between.  My custom version of BLHeli multiplies the signal by 1.5 to bring the 8kHz calculations up to 12kHz and this makes the throttle perfectly linear.  Also attached are patch files that show the source changes I made.  I built versions using BLHeli 9.4 and 10.3.  I use 9.4 but the latest BLHeli is 10.3.

BLHeli 10.4 now supports 12kHz so no need to use my version of BLHeli unless you want to run an older version (I currently still use 9.4).

V922 brushless ESC
V922 brushless ESC installed

WLToys V922 brushless test 3D

New paper canopy, although I think I’m going to end up using this on my mCPX.  It’s made with card stock which is a little too heavy for my liking (3.7g).  I’m going to try to make another with lighter materials.

V922 custom canopy

Posted in Projects | Tagged , , | 27 Comments

Skyartec TX module for the 9x

Skyartec TX logo

This is a TX module for the 9x that works with Skyartec receivers (eg. Wasp 100 Nano CP, etc). It uses an off-the-shelf generic CC2500 module (eBay/China) and has an integrated LNA that provides 100mW output. The RF module is controlled by an Arduino Pro Mini board which converts the PPM signal from the 9x to the Skyartec protocol.  The TX module runs at 3.3V and uses a single 2N7000 MOSFET for level conversion of the 5V 9x PPM signal.

I fly with a fairly low power setting.  If you look in “skyartec9x.ino” at the skyartec_init() function the power output can be increased.  The current code looks like:

CC2500_WriteReg(CC2500_3E_PATABLE, CC2500_97_PWR10DN);

  That can be changed to:

CC2500_WriteReg(CC2500_3E_PATABLE, CC2500_FF_PWR1UP);

for maximum power.

This is the CC2500 module I used:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=121064278513

Although almost any CC2500 module will work.

I use a separate power supply and 9x interface board that supplies the 3.3v and PPM signal.

Skyartec Wasp 100 Nano CP with Turnigy 9x

Posted in Projects | Tagged , , | 8 Comments

JSON encoder and decoder for Lua

My implementation of JSON using the LPeg library.

Posted in Programming | Tagged , | Leave a comment