First order of business after arriving: food. The last two times I was there as a poor student, we never splurged on food, but now as working professionals, I can! Frog legs? Okay.

With the Eurocup games being hosted in France and the terrorist attacks that happened in Paris, there were soldiers on the street in just about every place with crowds. If any terrorist attacks were to happen in Paris, it wouldn’t be during the Eurocup games.

Later that night, we met up with one of our friend’s coworkers for dinner. Time for more food. Escargot? Okay.

Beef tartare? Okay. We all had one for ourselves, and if anything bad were to happen, there was only one washroom in our AirBnB. Would have been game over.

The next day, we went to Versailles. Instead of taking pictures of things, I played Pokemon Go instead. It had just launched in USA, and since I had an account from that launch, I got to play. Everywhere I went, there was Pokemon. Never mind that it was a blazing hot day without much shade in the palace gardens. Gotta catch’em all. It was Pokemon Go everywhere I went – there’s even an arena at the Arc de Triomphe.

Make Napoleon great again!

After all the walking around, it was time for more food. Foie gras this time.

The next day was a trip to the catacombs and saw the skeletal remains of a lot of dead people.

And also visited a famous dead guy: Napoleon.

After that, it was time to go to the fan zone at the Eiffel Tower to watch France VS Portugal. All these people are trying to get in through the many entrances. The police guarding the gate were letting women and children go in without lining out while everyone else had to. Chivalry is alive and well in France.

After a long while of waiting we got in. There were so many people walking on the gravel road that it kicked up so much dust everywhere and it was hard to breathe and I was coughing every few minutes. It wasn’t comfortable at all. There were long lineups everywhere and nowhere to sit. But the atmosphere was really good. Lots of cheering and anticipation for a France win.

A friend of ours, who was coming from another location came too late and couldn’t get into the fan zone to meet up with us. After a grueling ordeal of deciding whether or not to stay or go, we left and watched the game from a small restaurant near our AirBnB.

After Portugal won, people still cheered in the streets and set up firecrackers and stuff. I couldn’t have imagined what it would have been like if France won. All the France fans would have lost their shits and the streets would have been even more rowdy.

The next day, it was time to fly back home, thus ending my 3rd European adventure.

Link to photo album: here

1.0 Motors

The chosen motors are:

• Finger grasping – Cytron IG32E-264K at a cost of USD $57.03 from RobotShop
• Finger sliding – Cytron MO-SPG-30E-20K at a cost of USD $22.58 from RobotShop

Both motors meet the torque speed requirements for this project.

1.1 Finger Grasping Actuation

From the initial budget, the budget set for actuators was set at $325.  The torque requirement needed for gripping was also calculated and each finger would require 4 Nm at its output to lift a 4 kg object using only the fingertips.  The evaluation criteria states that the device grasp as fast as possible and that the client would have the highest satisfaction if the device cost was less than $700.

Looking on several websites that sold motors, the following DC motor was chosen: Cytron IG32E-264K at a cost of USD $57.03 from RobotShop.  The specifications are as follows:

At 12 V with gearing included, the stall torque would be 20.7 Nm (without consideration of mechanical efficiency).  A motor with a high stall torque is also beneficial because it lowers the gear ratio required, which leads to the use of less space for gearing.  The motor also comes with its gearing, which contributes to its high torque.  Given the high stall torque of this motor addition gear reduction is not required.  During grasping, the motor will be exerting high torque at low speeds and therefore, the motor will be operating near the stall torque.  The torque here is more than sufficient even with mechanical efficiency losses accounted for.

For finger actuation before grasping occurs, there is a low load and therefore the motor will be operating closer to the no load speed.  The no load speed with gear reduction is 27.7 rpm (without consideration of mechanical efficiency).  Split among three output shafts, the speed would be 9.21 rpm.  Even with the load of the fingers accounted for, this is still acceptable. based on requirements and evaluation criteria.

While the torque is a lot higher than required, this motor was only more expensive than a motor of one size smaller by less than three dollars.  The electrical characteristics were also identical.  With a higher motor torque, the grasper would be comfortable in lifting objects even heavier than 4 kg, which is another benefit based on the evaluation criteria.

1.2 Finger Sliding Actuation

The motor required here does not require a large torque since motion in this degree of freedom is not expected to handle heavy loads.  This motor only requires enough torque to overcome the friction of the finger on the power screw that it is mounted on.  Therefore, a low-cost motor (relative to the grasping motor) will suffice.  The DC motor of choice is the Cytron MO-SPG-30E-20K at a cost of USD $22.58 from RobotShop.

The specifications are as follows:

The consistency of the stated specifications do not match the previous motor because the information that was provided by the manufacturer was not consistent.

An initial estimate of two 200 g fingers sliding on a 1/2” diameter power screw with a steel-steel sliding interface (friction coefficient of 0.8) shows that only 20 mNm of torque is required.  Therefore, this motor meets the requirement.  The power screw also has 13 threads per inch, and at the rated 185 rpm, the power screw would slide linearly at 6 mm/s.

1.3 Motor Type

DC and servo motors are motors that are suitable for the project.  An investigation between DC and servo motors showed that many manufacturers of motors did not provide the necessary specifications for choosing a servo motor in terms of the values of the no load, stall torque, and stall current.  While servos generate a lot of torque relative to their size when compared to DC motors, it is not feasible to use a servo motor because of the unknowns in the specifications.  It is possible to buy several servos and test them, but this is costly and time consuming.  At this stage in the project, the team is not able to commit the time to investigate further.

Comparison of the cost of the grasping motor relative to motors from Maxon Motor, a supplier of motors for UBC Thunderbots, shows that the price of a motor of the same power output costs approximately the same amount.  However, a fundamental difference is that the motor from Maxon does not include a gearbox, while the chosen motor for this project does.

2.0 Microcontroller

The microcontroller of choice is the Arduino Diecimila.  The primary motivator for using this board is because the UBC Thunderbots team already has this board and is currently unused.  The Thunderbots team has generously provided the board for use on this project.

The MCU will allow the turning the motors on and off, changing motor direction, changing motor speed, and reading encoder feedback.

3.0 Voltage Regulation for Encoders

Since the power supply is likely going to be run at 12 V, the encoders will require voltage regulation down to 5 V (the operating voltage of the encoder for the motors).  The chosen voltage regulator is the MC78L05A at a cost of USD from Digikey.  According to the typical application diagram of the datasheet, two capacitors will also be required (0.33 μF and 0.1 μF).  The cost of these are less than $1.

The voltage regulator will be wired up in this way as the datasheet shows:

The input will be from the 12 V source, and the output will be to the encoders.

4.0 Motor Driver

To control the motors, an H-Bridge is to be used.  However, due to the different current flows for each motor, one motor driver will require a high current capacity while the other one will not.  The high current capacity motor driver consists of a driving circuit using two half-bridges.  The low current capacity motor driver is made up of 1 IC.

4.1 Finger Grasping Motor Driver

To design the H-Bridge for controlling the motor, an L6205 motor driver will be used.  Each of them costs USD $11.36 from Digikey and can withstand a continuous current of 2.8 A and a peak current of 5.8 A and can be interfaced with the microcontroller with PWM inputs.  The driver can also be run in a parallel mode to double the current ratings by using both of its full bridges together.  The datasheet provides an application circuit as follows:

Output pins from the Arduino can turn the motor on and off through the enable pins.  Direction is controlled by adjusting the voltage polarity between IN1 and IN2.

There are also two output pins for current sensing.  By using it to measure the current draw, the microcontroller program can determine what the torque is through the use of the motor curves provided in the motor specifications.

4.2 Finger Sliding Motor Driver

The motor driver of choice is the L293D and each one costs $2.50 from Digikey.  Bidirectional control of a DC motor can be achieved by adapting the application circuit from the datasheet:

The 1A and 2A pins determine the direction of the motor or the motor deceleration.  A truth table is provided in the datasheet.

5.0 Power Supply

To power the grasper, a power supply plugged into the wall will be used.  It is expected that the future robot will have a power source of its own which will power the hand as well.  Therefore, for the purposes of testing the grasper for this project only a wall power supply will be required.

Looking at the maximum electrical power consumption of the two motors, the total comes to ~65 W (12 V * 5 A + 12 V * 0.41 A).  The other components also consume power and so the final power consumption will be higher.  To compensate, a 12 V power supply with a maximum wattage and current of 84 W and 7 A was selected.  The part number is CENB1090 and each costs USD $70.48 from Digikey.

6.0 Power Supply Connector

The power supply chosen has one port that uses a Molex Mini-Fit Jr. Receptacle.  Therefore, a proper receptacle must be used so that proper wire routing can power all the circuitry.  This also means that the future robot will also require a matching plug for this receptacle.

7.0 Fuses

Fuses will also be used as a redundant mechanism to stop the motor in case the current draw is too high.  The primary method of stopping the motor is through the current sense pins on the motor driver.

This guide presents how to mimic the system used in professional karaoke establishments at home.  The software this system uses revolves around a Taiwanese program called JetKTV.  Much of the content from this guide was drawn from Chinese language websites discussing the usage of this program (scroll all the way down for References).    There is little literature on this subject in English and so this guide presents basically an English version of the reference sites plus a few added notes.

The program used is in Chinese, so people who are not fluent in Chinese may have a hard time navigating through the software.  Those who are brave enough to continue or have a basic knowledge of Chinese with better English fluency may find it helpful to see English instructions.  The Chinese sites on this subject are also written for older versions, and the setup procedure for those older versions are slightly different.

Contents

• Proposed Setup
• Setting Up JetKTV2010
• Inserting A New Song
• Inserting A New Artist
• Testing
• References

Proposed Setup

The proposed setup of all the hardware (TV’s, amps, computer, etc.) is in the diagram below.

The computer will play the chosen Karaoke videos and transmit the video signal to the TV (via extended display like in a dual monitor set up).  The computer’s audio will go to an amplifier or a mixer, which is then transmitted to a set of speakers.  Microphones are plugged into the amplifier/mixer is well so that the speakers can also play the sound picked up by the microphones.  Depending on the hardware, the cables could be different (some TV’s may not have HD output etc.)The  computer is the source of all the signals transmitted to the other devices and must be set up with the Karaoke software.

Setting up JetKTV2010

The PC will use the following software:

• JetKTV2010 (link)
• SongMgr (optional – not helpful on English language PC’s – more on that topic later)

It is helpful to set up the software using a dual monitor setup.  That way, it is easier to test without having to go and plug the computer to the TV each time.

Unzip the contents of the JetKTV2010 program in a folder and open JetKTV2010.exe.  The GUI buttons are for searching through the database (by looking for the artist, song name, etc.) to find the wanted song. Once a song is selected, it will be added to the list of songs to play just like the software at actual Karaoke establishments. The video will play in full screen on one monitor and the song picker GUI will say on another monitor.  To close the program, click on the top left corner of the GUI (hidden button).

Some of the software features in addition to searching and adding songs:

• Skipping songs
• Fast forwarding, pausing, etc.
• Switching from one audio channel to both audio channels (alternating between vocal on/off)

This program reads from a database that contains the song names, artists, language, etc.   Therefore, it does not come with songs.  Songs must be downloaded separately and added on.  These can come from existing DVD’s or YouTube.  The next section will explain how to populate the database.

Populating the Database

The SongMgr program mentioned above can add/remove contents from the database, but there are problems with it when using it on English language PC’s due to problems in encoding some of the Chinese characters.  Even Microsoft AppLocale fails to rectify the problems.  The solution is to use Microsoft Access to open up the database file directly and make changes.

Adding one song can seem like a lengthy process at the first try, but it will get easier as one becomes more familiar with the system.

Inserting A New Song

To insert a new song, one must navigate to the table where the songs are stored and then add an entry to it.

1. Open Song.mdbin the JetKTV program directory
2. When prompted for a password, input “tmwcmgumbonqd” without quotes
3. Navigate to the table Tbl_Song.  This is the table that records all the song entries.

Below is an explanation of each column:

• Song_ID: numerical identifier for each song (the program lists them as 5 digit numbers starting at 10000)
• Song_Title: song title
• Song_Singer: each singer has a unique number associated with them (see next section)
• Song_Singer (2nd one): the name of the artist in text
• Song_Word: number of characters in the song name
• Song_Type: a number representing a language (Mandarin,Taiwanese,Cantonese,Hakka Chinese,English,Japanese,Movies,Cartoons,Other  in that order starting from 1)
• Song_Volume: song volume, but not sure what units they are in.  Default value is 70.
• Song_Channel: the audio channel that does not have the vocal track. (1-Left, 2-Right, 3-Both)
• Song_FileName: filename of the video without the directory
• Song_Path: the directory to the file (could use absolute pathing only, but unsure of whether relative paths work)
• Song_Create: the time that the song was added in
• Song_Count: the play count of a song
• Song_Juyin: the Zhuyin characters representing the song title
• Song_Stroke: number of strokes in the first character of the song name

Some of the columns can be left out, but that means that it will not be possible to find a particular song using the omitted information.  For example, Song_Juyin can be left out for those who dont use the Zhuyin system, and that feature won’t be used for song searching anyway.

To add a song, fill out the following information at the minimum on one row:

• Song_ID (must be a unique number and should have five digits)
• Song_Title
• Song_Singer
• Song_Volume (70 is the default)
• Song_Channel
• Song_FileName
• Song_Path

For the Song_Singer information, refer to the next section.

Inserting A New Artist

Artist information is stored on a different table called Tbl_Singer

1. Open the table called Tbl_Singer
2. Fill out an entire row to add a new singer (see below for the reference for each information column)

Below is an explanation of each column:

• Singer_ID: unique identifier for each singer (this is the unique ID that is to put inserted in the Song_Singer column in Tbl_Song)
• Singer_Sex: singer gender (0-Female, 1-Male, 2-Group/Band)
• Singer_Name: artist name in text
• Singer_Juyin: the Zhuyin characters representing the artist name
• Singer_Stroke: number of strokes in the first character of the artist’s name

Testing

One a song or two has been entered into the database, one can test it by opening up the JetKTV program and trying to pick a song.  It is working when one screen shows the video playing and another screen showing the JetKTV GUI.

One can also try clicking the button labeled “導唱” to test if the audio channels are set up properly (toggling it turns on and off the vocals).

The next step would be to plug in the computer with all the television components and then trying it again.  Once everything works, the system is ready.

References

All reference sites are in Chinese

[1] 動手打造窮人 KTV <http://www.jetktv.ktvdiy.com/> [Update 2022 October: JetKTV seems to be defunct]

[2] [影音相關] JetKTV 輕鬆打造免費 KTV 點唱機 (進階設定篇) <http://www.soft4fun.net/video-related/%E5%BD%B1%E9%9F%B3%E7%9B%B8%E9%97%9C-jetktv-%E8%BC%95%E9%AC%86%E6%89%93%E9%80%A0%E5%85%8D%E8%B2%BB-ktv-%E9%BB%9E%E5%94%B1%E6%A9%9F-%E9%80%B2%E9%9A%8E%E8%A8%AD%E5%AE%9A%E7%AF%87.htm#doublescr>

[3] 峰網誌 JetKTV-DIY電腦點歌機..軟體篇 <http://www.wretch.cc/blog/Linpy/4853370>

After almost four years of using my Inspiron 1520, its age finally caught up with it and its light literally went out.  The backlight refuses to turn on now.  I came back from Berlin last Monday and found my computer in this state.  I left it off during that time too.  During this time, I had trouble doing any blogging and uploading any photos.

Google told me that the problem lay with either a loose connection, the inverter or the lamp.  I tried to check this out myself and open the computer case, but the screws refused to budge.  People online somehow got theirs open, but I couldn’t.

Unfortunately, my warranty expired so I’d have to pay to get this computer fixed.  I looked at my options on the Dell site and the North American Dell Support refused to help me and kept referring me to the European side even though I bought my computer in Canada (I really don’t know what these guys at the call centers are doing).  After about three calls to the support line, I finally found someone helpful and she told me that I had to change my laptop registration such that it showed a European location before I could get it fixed.  An alternative option would have been to send the computer back to Canada to get it fixed.

What I did instead was just buy a new laptop.  My laptop is already super old and already can’t really keep up with my tasks anyway, so I suppose it’s time for an upgrade.  What surprised me was that laptops in Germany (from their Best Buy/Future Shop equivalents anyway) cost so much more than in North America.  In fact, it was cheaper for me to buy my computer in Canada and get my parents to ship it to me rather than buying it locally.  I’m sure there are cheaper places, but I don’t exactly know how to look through all these German websites.  Another added advantage in buying from Canada is that I’d have a computer with the US Keyboard layout rather than the German one.  And in the future when my laptop needs repairs, it’ll be easy.

In the meantime, I’m using a 17 inch LCD screen that I borrowed from a friend.  This will suffice until my new computer arrives.  No more shining a lamp at my computer screen and squinting my eyes to see the screen anymore.  I also don’t need to be using my phone to go on the internet at home either.