An Arduino DIY Tachometer Display

The goal  of this project was to create some sort of display that would retrieve and display the rpm signal in an easy to read manor. I thought it would be nice to see this information while driving to see how the engine and the transmission react to different conditions. Though it maybe phased out by my custom touchscreen media center i'm working on now. That device would use a bluetooth OBDII reader that would give me much more than just rpm.

Using ADB and fastboot With Your Android Device

If you have found this page you are probably frantically looking for some fastboot or adb command and that's what I will give you - scroll to the end of the post and you'll find examples. For all you other people who are not freaking out about their bricked or non-booting phone...continue on. haha. 

What Are fastboot And ADB

fastboot and adb are two programs found in the Android development SDK that allow you to transfer files, install programs, flash images, and run commands on your Android phone. Another thing to note: ADB can only connect to your phone while it is in recovery or booted into the OS. fastboot can only be used when your device is in bootloader mode. Finally, one of the most important things (i think) in terms of android is to access the bootloader: turn off your device and hold Power and Volume Down at the same time. 

SDSMT FSAE Adventures?

Now that i'm in college i can finally join clubs that i can actually do fun stuff in. High school robotics was ok, but that doesn't compare to racing a Formula SAE car around a track. My college has had this program for a while so we have some older cars for new students to drive (dubbed the 03 car). It had some issues so we had to fix those first before driving.

This is the 2003 car for new drivers. 2012 car seen on left

Modding the NERF 6 Barrel Strongarm (Barrel Drop / Swap Mod)

Here at college we have Humans vs Zombies where we use Nerf guns to hunt down zombies (i think there's an assassin game later in the year). People have been buying Nerf guns for the past few months and modding them for better performance (pretty sure Walmart loves it haha). I got the Strongarm and then another one a few weeks later for driving someone on some errands. That means I could then do the barrel swap mod which allows for easy swapping of 6 rounds without having to reload individual darts after every shots. 

Here's an original Strongarm (notice the grey barrel supports). These are the main parts we'll be modding. Ok, stock except for the missing grip, haha.

Fixing "New XAMPP security concept" and "Port already in use" Errors With Apache

Now that im at college and have a decent internet connection, I wanted to try some cloud style music access. And by "style" I mean running my own server from my desktop with all my media and accessing it from my school issued laptop so i don't have to carry around all the music. I first tried Orb which basically installs a program on your computer and creates a database of your media and when you use their website to remote access it their servers contact your computer and stream the media to the remote computer. There are two problems with this: Orb is shutting down soon because it was bought out and media stream was in shitty quality. I then started to look for open source options that dint require a man-in-the-middle server to stream the media (aka i wanted a direct pipeline). I found the perfect choice: Ampache. Its based off of Apache (a basic, but powerful web server) and MySQL. I liked all of its features except that you have to do some server tinkering and i have had little experience, but it was actually quite easy because Apache and MySQL have been put into an installer package called XAMPP which makes it really easy to setup. There are step by step instructions here. Quick note: when installing XAMPP you only need Apache and MySQL for Ampache to work.

Using an Tiva-C Launchpad With Energia (Ardunio IDE for ARM)

If your'e a daily Hackaday reader you should've seen this post a week or so ago. It links to this ARM forum topic: some guy found a 25$ multi-use coupon and shared it with the community.  He and many others bought two tiva-c launchpads for a total of .98$ with the coupon (you can buy anything ya wanted but might as well get some MCUs). I was lucky enough to catch this before the coupon was discontinued and got my two launchpads and then went and searched on how to use them  There is of course the official TI C/C++ compilers or programs, but i wanted to go with something I already knew: Arduino. I remembered the Energia project from a while back that does exactly what I wanted: it uses the familiar Arduino "Wired" code and a similar IDE.

My Custom Android 2.2.2 Froyo Rom for LG Apex (US740)

In this post, i'll be writing about my adventures in creating a custom rom for a LG Apex (US740) on Froyo version 2.2.2. :)

This is What I Do When I'm Bored at Work

 Yes, that's right, schemes drawn on Home Depot receipts.

How to EASILY Dump your Android's Rom!

Well, I guess that is relative. There is no one click method for this, however, this the easiest i've found.

How to Root Any Android with Froyo (2.0)

The goal of this post is to show you how to root an Android device that runs the Froyo firmware, aka v2.0. I  found a LG Apex in the electronics recycling (pretty rare to find an android) and of course wanted to tinker with it. Just like with any other new project, you need to read as much as possible so you dont screw anything up. Rooting is actually quite simple: people have made programs that do it for you (just a few clicks).

Some Management Stuff

I have made a few changes and am thinking about a few others. I changed the templates to something a little easier to read and see hyperlinks in text. I also found some new code box html code. Do you like the new stuff? Should I do page breaks in longer posts (lots of scrolling)?

That is if anyone cares :)

R/C Themed Car Media Controls

The goal of this project is to interface some sort of media player with my radio with media controls easily accessible. After washing my ipod and the cellphone battery not fixing it (soemthing was drawing excessive current and killing the battery within a day of not being used (a new ipod battery didn't fix it either). So i set off with another idea: use my netbook.

Why?
-has my entire music collection
-can be interfaced with an arduino through processing.
-arduino will handle all the control interface reading.
-runs linux which is awesome
-Amarok media player
-small

Replace A-Arm and Steering Assembly on 1/16th scale 25A SCT RC from HobbyKing.

First off NEVER EVER drive these RCs without the body unless your are on some flat, huge surface. Hitting something will most likely break off the A-arms without the body protection. Long story short, I broke one and finally did this repair after the ~9.00$ of parts came in. I got all of these parts to be less than the first tier ~100g package, so shipping was only ~2.00$ :D.

Dogbone 2 pcs - 118B, A2023T and A2035 1 IN STOCK Front Shock Complete 2 pcs - 118B, A2023T and A2035 1 IN STOCK Front Susp.arm - L/R 2 pcs - 118B, A2023T and A2035 1 IN STOCK Steering Drag Link 1pc - 118B, A2023T and A2035 1 IN STOCK

The parts.

RC Power Wheels Jeep

This post is about the Power Wheels Jeep I found in my neighbors trash while working on the Racing Wheel project. I plan on slimming it down, PAINTING IT, and turning it into a RC Power Wheels (on a low budget).

When I saw it, I was thinking it would be very unlikely any thing was severely wrong with it. 

DIY Computer Racing Wheel Setup

The main goal is to build a Racing Wheel for a computer out of a soon-to-be-scrapped 92 Ford Taurus. Since it's going to the scrap, it doesnt really matter what happens to it. Hehe. So, I've been taking apart random parts to learn about them. :) The  photos area bit lacking but should get the point across.

There she is :D

OBDuino Project

The goal of this project is to interface an Arduino with car OBDII diagnostics to display telemetry for the driver. This project first started because I wanted a tachometer in my automatic 2002 Prizm. I found one of those super cheap tachs on ebay, but hey, whats the fun in that? Here is a toyotanation (forum) post on that tach and install for most ~2000 Toyota Corollas. This tach works by reading the IGN or ignition pulse from the diagnostic port.

Disassembeling a LiPo

This is one of my first 3s LiPos that is pretty much useless now (wasn't damaged), so i decided to disassemble it.

Cut off the blue casing by taking an exacto knife. I cut a little notch and then it simply ripped down the case.

The balance connector and main terminal connectors

I didn't want to risk un-soldering, so, i carefully trimmed off the balance wires, then the main leads.  

To separate the cells, i used a plastic table knife and gently sawed them apart. The adhesive smelled really bad, but it at least it wasn't sweet ( a sweetish smell from a LiPo = fire).

As seen in the pictures, this 3S LiPo has three cells each with a nominal voltage of 3.7V and a capacity of 2200mah. Put three of these in series and you have 11.1V, the nominal voltage of a 3S LiPo battery. If the batteries is in series, the voltage increases, but the capacity is the same as the individual cells. In parallel the battery would have the same voltage as the individual cells, but the capacity of each cell is essentially "added". So, if these were wired in parallel, it would've been a 1S (3.7V) 6600mah LiPo battery.

And as the Mythbusters have said:

(All rights given to uploader and original content provider. I don't own this or the content.)

Yet Another Original Car Radio Aux Input Mod

Yeah, bad title, get over it.

Background

I got a new car because my 92' Taurus's ECM (the brain) decided to crap out. We decided it would be better to just get a new car. Oh, and this was in the middle of the interstate :D. Which meant that the motor suddenly stopped since nothing was controlling the motor electronics. Since i was going 70mph, it was quite easy to pull of to the side and think "what the hell" ?!?!?

I poked around craigslist and found one of the cars I've always wanted: a 1999 Mitsubishi Eclipse. This didn't work out because i'd know they were all owned by younger people and therefor shitily driven. Still wanting a Mitsubishi, i found a Lancer, but the same story. I settled on a 2002 Chevy Prizm for a good price. it doesn't have many features, but it gets 37 MPG. meh, it gets good mpg, "screw looks" i basically said. It actually had a CD player, so i didnt really mind no aux-in port. this soon changed.

While using it, i noticed the buttons were all extremely hard to push. Meh, whatever, i only need the main volume/power encoder, so i didn't really care. And then CDs stopped working. I'm screwed. I never listen to FM because i have no local Techno etc stations. i have ascended to the best music. So i took this radio apart, and surprise, surprise: pop all over the inside. It seem the previous owners spilled a bit. I started cleaning and soon realized that i couldn't do it by hand. So i walk over to the sink, fill it up with hot water and i wash my radio :D. FYI, it is the minerals in the water, not the H20 itself that fries electronics. Then i did a few rinse cycles in distilled water (pure H20), and dried it. The radio still works just as it did before the wash: no CD player.

Theory Stuff

I then began the same search as i did in my Taurus radio mod for the audio lines to the speaker amplifiers on the PCB and therefor bypassing the controls entirely and allowing a standard 3.5mm audio cable to be connected for aux-in. i was still unable to find the audio lines from the FM decoder to the mixer chip so i'm stuck without mixer controls on the radio (bass boost etc).

If your CD player still works and you just want aux out, then look at these sites: here and here. Note that the Prizm radio is essentially the same as the ones in those posts, so the mod works. i'd guess a lot of stock radios from the 2000's would have a similar layout and the mod would also work. This method allows you to still use the bass, treble and volume buttons etc on your radio with your aux device and the CD player still works when you take out the aux cable.

The Mod

Pull out the Radio

Use a screw driver to pry the black console frame off at the red line. Make sure you don't damage the dashboard foam/plastic stuff. Or you could some how pull out with some 90deg hook tool at the blue line. After you get a side loose, then just use your hands and follow the perimeter with your hands pulling out.

Pull the black casing off to the side to get the radio out. 

Take out the four yellow marked screws. Now, pull the radio out and up just over the shifter. Then, pull off the antenna connector and harness.  

Here's my radio before the mod.

Take off the mounting hardware and case

These plates are held on by a few small screws, and just pull off. Also, note that these are weird bolts, neither customary or metric sockets fit. I had to use a pliers.

These are the mounts for the radio to the car dash.One bracket per side. Three 8mm bolts each.

All the plates and brackets

Search for the magical mixer IC output lines

CD Player Mechanism below the top plate. 

This was simply puled out after the case screws were taken out.

The top PCB after taking out the CD player mechanism. Hot glued the cable to the PCB.

The bare PCB below bottom plate. Where ill find the input lines.

Labeled PCB

Mixer outputs to AMP.

Then i just soldered a 3.5mm audio cable to the pads, and soldered a ground.

FrSky Voltage Sensor

One of the reasons I choose to upgrade my Turnigy 9x to the FrSky system was the telemetry(2-way) mode. This gives me signal strength data and most of all, the RX has two analog ports. These two analog ports (3.3v!) can be used for anything with a range of analog values. For example, with a few resistors, i made a voltage divider so that the 12.6v of a lipo is scaled down to 3.3v where it is then sent to the 9x and read out as a battery voltage on the 9x lcd. no need for lipo alarms! I have the ER9x firmware which made the frsky mod possible. also required here.

RX Setup

Here is the schematic. The color dots are the resistor color codes. AIN is A1 or A2 on the RX. Only connect one +. so if you had a 3s batt, you would connect it 12v+ to the 3s resistor.

TX Setup

Hardware Setup

-Build the above circuit for the battery you are using

-Connect it to the battery and RX(dont mess up polarity!)

Turn on your TX

-Power the RX with a bec or something

Voltage Calibration 

model page 10/12 (Telemetry 1)

-A1 channel 11.1v 13.0 line is showing the voltage of the battery 11.1v is a calibration value, 13.0 in this example is the actual battery voltage it reads.
-To set this up, measure the voltage of your battery with a volt meter. 

-Now this voltage should be in this screen. adjust the 11.1v number until the 13.0 number is equal to the volt meter reading

-press exit when done. now you have "calibrated" A1. 

-also, the the "v" from 11.1v can be changed to A for ex to measure the amps the model is drawing (with that amp sensor of course).

Alarms

alrm --- < 0.0v
alrm  --- < 0.0v

These are alarms you can set so it will beep when it is below certain level. 

-Select the "---" and choose yellow, orange or red. these would be the level of the battery. 

-Now, you can change the sign (< or >)most people will use less than (<) then you could set the 0.0v parameter to the a voltage that is related to the yellow orange or red. FOR example

alrm Yel < 11.1v 

this means you would have a yellow alert when the battery on the model drops below 11.1v

alrm Red < 10.0v 

this means you would have a red alert when the battery on the model drops below 10.0v
alrm Yel > 11.1v

this means you would have a yellow alerrt while the battery on the model is above 11.1v
alrm Red > 10.0v

this means you would have a yellow alert when the battery on the model is above 10.0v

Same for if you had a battery on A2

Model page 11/12 (Telemetry 2)
-TxRSSIalarm is a value to set for when the TX signal is less that whatever value. lets you know when youre going out of range
-RxRSSIalarm is the same for telemetry signal from the rx

-mAhalarm is for alarming you when you have drawn x amount of amps from the battery
-ALTalarm is for if you have a baro sensor and it will alarm you if you have gone too high.
-gpsaltmain uses the gps as a baro instead of the separate baro

-Custom Menu this allows you to change what values show on your Telemetry screen while using the TX. i did A1 A2 RSSI and TSSI

will add more pics :)!!

Assemble a HK 2-axis FPV Mount

I bought this to fill up one of my HK orders. Here is how i put it together

The parts in the bag.

The linkage endings. Press the little metal balls into the plastic.

Put them on the shaft like so.

Grab two servo horns like so. 

See if the holes will fit the bottom piece like so. If so, then use screws to hold the horn on to the piece. If it doesn't fit, you will have to use hot glue to hold it in place.

Like so.

Testing with a servo. Make sure you center the servo somehow before screwing it on.

Put the bearings in to the arms. Everything is press fit. Now, insert the camera mount plate into the bearings.

Put the little bearing covers on.

Once you have that, carefully spread the arms so that the base plate fits in (see bottom).

Put the servo arm on with the servo centered like so.

Use the itsy bitsy screws from the pack to attach the linkage to the servo arm and the base arm. i used a spacer on the servo arm for better movement. To get the angles right, i held the servo to the camera plate with my hand, and then used the HK servo tester to see what range the servo moved the camera plate. Then i moved it a bit up or down and repeated until the camera plate moved in a range i wanted.

FrSky DHT DIY 9x Mod with ER9x Integrated Telemtry

In one of my latest HK orders I got one of the FrSky DHT 8ch DIY Telemetry TX Modules. I'm definitely a DIY person and that's why i didn't get the 50$ module that fits in the JR style Turnigy 9x.
I needed:
-Single Core wire: for example: IDE ribbon cable.
-Xacto
-Solder stuff.
-9x with a programming header
-ER9x-FrSky firmware
-Basic hand tools

9x Mods

Ill start with the Turnigy 9x part of the mod. We need to move two aux switches to extra digital pins so that the original pins can be used for UART communication with the FrSky Module. Cut the traces, and solder on the two wires for RX and TX.

 

Open up the case.

Disconnect the cable between the two halves. Wiggle and pull gently.

An un-modded Turnigy 9x will look just like this.

I had already modded mine with the programming port, so mine looks like this. Except, it is slathered in hot glue to protect the programming wires from popping off. At that point i didn't expect to do another mod, so i didn't even think about how it would affect later things. That hot glue causes a lot of problems  here, so i recommend to do all mods at once or don't use hot glue. I had to carefully pick off the glue.

Cut the traces on the PCB where shown by the yellow marks. Use a sharp Xacto and be sure not to press so hard that you loose control and cut another trace. Check it with the continuity function of a multimeter.

Use the Thin piece of wire (seen in pic) to connect the blue marked spot to the blue pin on the top side of the atmega64. Same for red. Use a bit of flux and be sure to not bridge anything. Check for no continuity again.

This image shows what we are doing next, and also is a brief overview of what we just did. The GND, VCC, MOSI, MISO, SCK, and RST bubbles need to be connected to a programming header so that we can program the ER9X-Frsky firmware. Then there are the two bubbles that have two labels: RX0/MOSI and TX0/MISO. These two pins double as the TX and RX from the FrSky telemetry module and for programming now that the AIL and THR switches are on other pins. Thanks to Marc G at rchacker.com for this image: original post.

This is looking into a female 6 and 10 pin isp connector. Simply connect all of the pads on the board to their respective pins on the connector. Then take two more pieces of wire and solder them to the MISO and MOSI pads so that they can go to the FrSky module.

My Results

As i mentioned before, i had issues with hot glue. This is what i ended up with (working!). In the first test i realized that the THR and AIL switches were mixed, so rather than re-soldering to the atmega use IDEcable wire), i just cut the wires before and swapped: green to brown and vice versa. The next screw up is the resistor wrapped in tape. I couldn't get a wire connected to the SMD resistor right next to the TX0/MISO pad, so i put in a through-hole resistor. The caps at the top left are to replace the 22uf one that blew when i plugged the battery in with opposite polarity: i was lucky that i didn't blow anything else! As you can see this mod isnt without risk, but now i could nearly do it in my sleep (so to say)!

FrSky Module Mods

In this part we will open the FrSky module and grab the TTL level TX and RX to connect with the 9x. The FrSky module converts the 3.3v TTL to RS232 as it has better quality but this outdoes matter for the distance from the FRSky module to the atmega.. We don't need RS232 since were going to the atmega and dont want to spend 50$ for their telemetry JR module. This mod involves cutting a few traces, and soldering some wires and resistors. The important thing to remember here is that the FrSky module runs at 3.3v so we might need to do a little protection between it and the atmega 5v (like the 3.3v bluetooth module).

The bag from HK 

The top one is the included 2db antenna. below it is a 5db antenna that I've had laying around. This is a a pretty important topic. The higher the "db" of an antenna, the higher signal power, but this comes at a sacrifice. More power means less unidirectional distribution of that power. If you have a high gain antenna  you risk loosing control of your model because of this narrower range of power, if you don't use these antennas properly. To deal with this people have made antenna trackers. Basically, these have super high gain antennas that are pointed to the model at all times using GPS, so no matter what, it will have good signal.

Here is the binding PCB with an LED and a momentary switch.

the SMA connector with the 2db antenna. NOTE: NEVER EVER turn on the TX without an antenna as you risk frying the transmitter module. It's sorta like a LED with 5v: you must have the resistance, or it will fry because of too much current.

The RX mode toggle.

TTL Level FrSky Module Output

Cut open the case (Careful!). It's some sort of thin, hard plastic shell. Rips pretty well.

Cut traces marked by yellow

and here

Scratch off the light green protective layer over the TX and RX lines so we can solder onto them. 

TX/RX pins on the FrSky module.

Solder a wire from TX (next to the MCU) to the TX on the pin header (red line).

You have two choices to connect the RX line:

1. The atmega RX can take these 3.3v levels from the FrSky TX. The RX of the FrSky will need the resistors as a 3.3v MCU isn't compatible with 5v on the serial port. Put a 20k resistor from the FrSky RX pad to GND and a 10k from the RX pad to RX on the pin header. (Safer)

2. These STM MCUs (processors) are 5v tolerant. That means you can hook the STM RX pad directly to the RX on the pin header. Just be careful with the wiring. This is shown in the first picture above. (i did this; no issues) 

Now connect FrSky pinheader TX to RX (MOSI) of the atmega, and FrSky pinheader RX to atmega TX (MISO)

Connecting to the 9x

Power, Ground and PPM connect to pads I have pointed out on the top of the main board. Some people unscrew the main board and solder to the bottom of the connector (the one just to the right of all the labeled wires) that goes to the other half of the TX. That doesn't make sense as these front side solder pads are so much easier to get to.

Frsky wire : 9x Connection

Black        : Ground

Red          : +12v

Yellow:      : PPM

Ignore the wires. This pic was from a different mod, but gave me what i needed for the markings.

Switches

Mount these some where on the outside of the case so you can change modes quickly. the toggle is for changing between 1-way (a regular RX), 2-way (receive telemetry from the RX to your TX), and the FW setting fro uploading new FW to the FrSky module. The button and LED are for binding.

I'd recommend putting the toggle somewhere else. Mine got in the way of the antenna a bit and required some extra work.

You're Done! 

Enjoy longer range, signal strength, telemetry, and that feeling of accomplishment. Look in the manual you received with the FrSky DIY module for binding instructions.

The final insides. I used tape because the original plastic cover was ruined (you wont see it anyways :D).

Credits!

Big thanks to Zen09 from RCG for the FrSky TX/RX pictures and rchacker for it's picture and info!