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This is my school project for the 5th year of high school (I'm Italian, we have 5 years of high school).

It consists in an artificial hand controlled by a glove with flex sensors. The artificial hand reproduces the movements of the hand with the control glove, wirelessly. The hand and the glove works both with Arduino.

I just wanted to share my work for everyone interested :)

This guide is still in development, sorry if some parts are not clear, I'll put some 3D images in future.

I'm sharing something about my project on my facebook page: https://www.facebook.com/Gabry295

Step 1: Materials needed

I bought almost everything from https://www.sparkfun.com/, they have fair prices (I don't mean to advertise!)

Total cost: ABOUT 160$

Materials for the control glove:
• an elastic glove;

LilyPad Arduino board (there are different versions, which usually only have 4 analog inputs, so pay attention and buy the one in the image): it works exactly like the classic Arduino UNO, so you can use even an Arduino Nano, but pay attention to the voltage needed;

XBee module: for the radio communication;
Shield to connect the Xbee module;
• 5 Flex sensors;
• 5 resistors: 47 KΩ;
battery pack with 3x1.5 V batteries (Lilypad can be powered from 2.7 to 5.5 V, so 4.5 V it's ok);
LilyPad FTDI adapter: to connect the LilyPad board to the PC and load programs with the Arduino IDE (quite optional, because you can use also the Arduino UNO board removing the ATmega chip, but it's tricky to make this kind of connection every time).

-

Materials for the robotic hand:

• a steel structure for the palm of the hand and wood for the fingers;
Arduino UNO board;
XBee module;
• 5 servomotors 5V powered (I used TowerPro SG90);
• a servomotor shield for Arduino UNO: to connect the servomotors I used the Robot_Shield from FuturaElettronica, which has also a switching regulator to power the entire circuit, but you can use any shield made for controlling servomotors. Link: https://store.open-electronics.org/index.php?_rou... ;
Shield to connect the XBee module (I made an horrible one, but it's economic and I needed to make one small because of the size of the Robot_Shield);
fishing wires;
• (optional) fihing sinkers, to secure the fishing wire, can be done also simply making a knot;
9 V Battery.
-

Tools needed:

angle grinder (mainly to cut wood and steel);
axial grinder;
welding machine (with electrodes);
drill;
soldering station and solder;
• electrician's scissors;
pliers;
heat shrink tubing.

Step 2: Making the glove

To make the control glove I suggest first to choose the right position of the different components, then connect everything with the proper length of wire.

To make an analog read with Arduino LilyPad you need to make a voltage divider, since that flex sensors don't work like potentiometers (they have only 2 contacts).

So following the scheme, first solder the 5 resistor on the LilyPad board, one side to the 5 different Analog pins, the other in common to the ground. Then solder the flex sensors, one side to the 5 different Analog pins and the other in common to the positive.

Then connect the XBee Shield: two wires for the power, the oter two for the signal. Solder the Tx pin to the Rx and vice versa.

Now you need the battery pack, and the glove it's done.

BE CAREFUL: don't power the Arduino LilyPad over 5.5 V and don't power it conversely (even if sometimes I did it by mistake... And it still works!)

Step 3: Making the Robotic Hand

This is the most complicated part, because you have to choose the proper materials to make the hand, but it can be also easy if you have the possibility to 3D print the hand (there are many different 3D projects on the web for printing hand parts).

I started making the fingers with cork, to find the proper structure for the movements, then I made it with a branch.

So make three wooden cylinder per finger, two of them with 1 cm over the normal lenght of your phalanx, needed to fit one piece into another.

Then with an angle grinder make the grooves to make the pieces fit together (see the images, you'll understand better).

You'll need some sandpaper to make the pieces curved, so that they can rotate.

Use a drill to make the holes for the hinge, then you have to make other two holes for the fishing wire, vertically, one towards the inside of the hand and one outwards. So when the wires are set at the top of the finger, when you pull the one inwardsthe finger will close, and when you pull the one outwards the finger will open.

The palm was problematic, beacuse I made it initially with wood and the thinner parts always broke. So I decided to make it of steel and I've had no problems.

Cut it and do some protrusions similar to those made for the fingers to fix them to the palm (see the images as a reference). Then use the drill to make the other holes for the fishing wire, the thumb will be tricky because it's not vertical as the ther fingers.

Afer making the hand, you need to make a support for the five servomotors and a support for the Arduino UNO boards. Be sure to choose the right position of the servos, so they don't touch each other while rotating.

The last part consists in connecting the fingers to the servomotors: fix the fishing wires at the top of the finger and make them pass through the holes; then, when the wires are at the bottom of the hand, turn the rotor (manually, without powering it) at his maximum rotation (180°) so that it's in a vertical position, then set the wire that closes the finger to the lowest hole of the rotor, for example making a knot; turn again the rotor at 0° (it's again vertical and the knot made before is at the top) then set the other wire (wich opens the finger) to the lowest hole of the rotor. Follow the last image in this step to understand better.

So, when the motor is at 0° (vertical) the finger is opened and when the rotor is at 180° (vertical again) the finger is closed.

Step 4: Circuit of the Robotic Hand

For the circuit, you can choose to use a servomotor shield for Arduino UNO (search on eBay or Amazon) with a XBee shield, or make a custom shield (I'll make one as soon as possible) with the XBee Module and the pins for the servomotors, and power the Arduino UNO by its jack port.

The DIY XBee Shield I made uses a 12 KOhm resistor and a 22 KOhm resistor, you can see the wiring in the pictures.

So I used what I had already bought before, but you can use everything that let you control the servomotors and the XBee.

The servomotors have 3 wires:

  • yellow: signal (connect to a digital pin);
  • red: power (+5 V);
  • brown: ground (GND).

So now you won't make mistakes :)

I used the simplest type of servomotor, working at 5 V, with a rotary angle of 180 degrees (that's the perfect angle, we don't need more).

The USB ports of a computer can't give anough power to control 5 servomotors, so I suggest to use a 12V power supply to test everything and then use the 9V battery (Alkaline are preferred).

Step 5: The programs

The program of the hand and the glove, with all description, are in links below.

REMEMBER: to load the program you have to remove everything connected to the TX and RX pins of the Arduino (in this case the XBee module), else the program won't load. Remember also to set the correct kind of Arduino in the IDE (LilyPad or Arduino UNO).

Links for the two codes:

https://codebender.cc/sketch:59559

https://codebender.cc/sketch:55013

Try this code to test the flex sensors on the glove: https://codebender.cc/sketch:56264

and this to test the connection between the Lilypad and Arduino Uno: https://codebender.cc/sketch:55014

Hello sir.i receive today my 5 flex sensors.i measured it with my multimeter and show<br>First flex bend(50K)and unbend(30K).<br>Second flex bend(53K)and unbend(28K)<br>Third flex bend(52K)and unbend(27K)<br>Fourth flex bend(51K)and unbend(32K)<br>Fifth flex bend(54K)and unbend(34K)<br><br>Which resistor i have to choose?can you help me please?and it is normal these values?thank you for your time.
<p>Hello, I found out that to have the best sensivity you should use a resistor that is the mean value of the max value and the min value: in your case: (50+30)\2=40KOhm.</p><p>In my case it's about 45K (I got 60K max and 30K min) so I choose a 47K resitor.</p><p>In your case you can use a 39K resistor, it's the nearest to the calculated 40K, but even a 47K should be ok.</p><p>Anyway the values you get are normal, unfortunately these sensors are not perfectly equal, but the code I wrote makes the calibration that should solve this problem :)</p>
<p>Thank you sir for your reply.I understand it.I choose 47K resistor.if i chosen 22K resistor would fried my flex sensor?Thank you again for your time.</p>
<p>http://www.amazon.in/Arduino-Lilypad-Main-board-AT... hi , i am using this lilypad . this is same as shown in image but its processor chip is different. so i buy it?</p>
<p>{http://www.flipkart.com/epro-labs-motor-drive-shield-dual-l293d/p/itmeggsdcxgmbdda?pid=ETYEGGSDN5GNTBRY&amp;affid=businessbu&amp;affExtParam1=buyt024&amp;affExtParam2=buyt024-574da5eadc39c23a438b4acb} I buy this one. How i needs to connect it with the xbee and motors for better control.</p>
<p>{http://www.amazon.in/s/ref=nb_sb_noss_1?url=search-alias%3Daps&amp;field-keywords=servo+motor+shield} which one will be better?send me link.</p>
<p>which one adapter u use ? Send me its link if it is on amazon.in , if it is not on amzon.in then there and many adapters , suggest me that which one i needs to use and also tell me about any motor controller on amazon.in which will able to control servo motors and if it is there then send me its link</p>
<p>[http://www.amazon.in/XBee-2mW-Wire-Antenna-ZigBee/dp/B007R9U1QA/ref=sr_1_fkmr0_1?ie=UTF8&amp;qid=1464628703&amp;sr=8-1-fkmr0&amp;keywords=4214A+xbee] Will this xbee work correctly? Tell me please....or give me a suggestion on my whatsapp no.9034157650 or gmail shubhamdhiman00.sd@gmail.com</p>
<p>Hello, that XBee it's S2, so you'll need to configure it with the PC before you can use it. I suggest a XBee S1 that is pre configured and you don't need to program it. Anyway the one you showed me can work as the one I used :)</p>
If my calibration values are 680 open and 430 closed what values should i use to get the servos to function? Ill send pics of the code manipulation we used. This is for the glove.
<p>I see you have modified the code, but you shouldn't need to insert the values you read, I wrote the code &quot;v2&quot; specially to do it automatically buy doing a fast initial calibration by closing the hand. So try to use the code as it is :)</p>
Like i said we had movement of a single servo with the values entered above but now with the values shown above we have no movement on any servos.
Like i said we had movement of a single servo with the values entered above but now with the values shown above we have no movement on any servos.
<p>Question. We have created a very similar project using the codes you have listed. Test functions are good with the glove and the arduino uno board, but the motor shield that you are using is not driving the motors, actually it will not recognize the code you provided. It looks as if the code you wrote does not include the code for the shield ie: servo1_pwm - servo5_pwm . We are pretty stuck right now on this project. If we use a standard arduino shield we can get individual servos to run but that shield is not stable to push 5 servos, but with the shield you recommended to use there is absolutely no movement of the servos.</p>
<p>Hello, did you provide the proper power to the circuit?</p><p>The Robot Shield doesn't need special function unless for the Servo function included in the library of the Arduino IDE. Usually the servos don't move when they don't have enough power, for example when you only use the USB plug. Try with only one servo, it should work even only with the usb.</p>
Yes the first day we tested a single flex sensor with a single servo connected to the arduino and it communicated and operated properly through wireless signal. We then built the remaining project, added the shield with the 8 servo connectors and finished the glove. We get the open/closed readouts on the serial monitor but no movement on any servos off that shield. We use approx 12 volts for the servos shield and 4 volts for the glove. We also used all the same resistance values for the voltage divider on the glove. Here is a picture of the glove with the rx/TX disconnected for programming.
<p>Well, so the important thing that remain is the current: you need a power source with minimum 1A of output, I used an adapter of a router (12V 1A)</p><p>I also use a 9V rechargeable battery, you need good quality, economics batteries can't provide enough current. But if you are using 8 servos I think it's difficult a single 9V battery can drive them all (maybe 2x9V batteries in parallel can provide enough current).</p>
<p>hi.I am very close to completing this project. The readings on the hand are showing some issues. The PIinky finger readings show only either 0 or 180 irrespective of the position of the corresponding flex sensor. Also middle and annular values change simultaneously even though i m only bending my middle finger. however the test readings on the glove are perfectly fine. Where did i go wrong and how can i correct this?? Thanks in advance</p>
<p>Hi,</p><p>you mean you tried the &quot;test code&quot; i put on the last page and it shows the correct values on the Serial Monitor?</p><p>If you mean so, it's really strange that with the GloveTx and HandRx codes you have errors... I suggest to check the connection and welds you made on the flex sensors.</p>
<p>yes, the test code for the glove works fine and gives good values but i dont get the same values when i run the test code for the robotic hand</p><p>actually the first two values are accurate sometimes but the remaining values are never correct</p>
<p>actually i modified the glove code to print the angle values so what i see in the serial monitor are mapped angle values.</p>
<p>I suggest to control the joints you made on the glove, if necessary make new connection.</p><p>Anyway the values you get from the glove don't have to be precise, but you need a quite &quot;linear&quot; passage of the values from 0 to 180 when you bend the finger</p>
<p>which flex sensor are you using? 2.2 inch one ya 4.5 inch one? <br>Thanks! </p>
<p>Hi, 2,2 inch is enough, it's the one I used :)</p>
Great job, thanks for sharing. I remember way back when I was a kid (8 years old) , I made a &quot;robot&quot; made of wood :). I was inspired by Mazinger Z, :). One of the chapters, kids had a robot competition... I made mine :). I was using hand saw-saw; I cut myself and I still have scarf in my hand. Be careful, don't cut yourself. :)
<p>hello</p><p>I am new to arduino and i tried building this project but it didnt work :(. probably because i have xbee s2 and i have not configured it correctly. If i directly connect the tx and rx pins of the lilypad arduino to the tx and rx pins of the arduino board using connecting wires, should it work?? I am asking this because i wat to know where i went wrong.</p>
<p>Hi :) if you have the XBee S2, you probably need to configure them via PC (you need the adapter). I'm sorry but I don't know how to configure them, because I know the S1 don't need it, you should search on google for it :)</p>
<p>Ciao Gabriele, mi sapresti dire come hai fatto dei fori cos&igrave; sottili e precisi nelle dita per far passare i fili?</p>
<p>Col trapano, usi una punta sottile: per far passare i fili ne devi fare due paralleli, e la posizione dei fori deve essere fatta in modo tale che il foro per la vite del vincolo sia in mezzo, nello spazio tra i due canali per i fili (se non sono stato chiare dimmi pure, provo a spiegarlo meglio).</p>
<p>Bro it is a wonderful project. But I am wondering that can you make a whole body rather than the hands only. </p>
<p>Thank you! :)</p><p>What you say it's possbile, for sure! I don't know what kind of motors I could use for wrist and elbow</p>
<p>HI EVERY BODY I JUST NEED THE CONFIGURATION OF XBEES2 </p>
<p>Hi, if you have the XBee S1 you don't need to configure the module :)</p><p>If you have other model I can't help you, but Google is the way ;)</p>
<p>Hello Gabry and everyone else.</p><p>I completed this project using a 3D printed hand from an open source robot called inmoov from<a href="http://www.instructables.com/id/Wireless-Controlled-Robotic-Hand/" rel="nofollow">inmoov.fr</a>. I then followed this instructable as well as another that was similar that used the inmoov hand. That instructable can be found at:</p><p><a href="http://www.instructables.com/id/DIY-Robotic-Hand-Controlled-by-a-Glove-and-Arduino/" rel="nofollow">http://www.instructables.com/id/DIY-Robotic-Hand-Controlled-by-a-Glove-and-Arduino/</a></p><p>I had some trouble using Gabry's code so I combined how he sent data between the two XBees with the code from the other instructable. You can follow my build and also see videos at:</p><p><a href="http://www.google.com/url?q=http%3A%2F%2Fbocabearingsworkshop.blogspot.com%2Fsearch%2Flabel%2F3D%2520Printed%2520Robotic%2520Hand&sa=D&sntz=1&usg=AFQjCNEjoGp7oconXGogKnPxpbA635eTWQ" rel="nofollow">http://www.google.com/url?q=http%3A%2F%2Fbocabearingsworkshop.blogspot.com%2Fsearch%2Flabel%2F3D%2520Printed%2520Robotic%2520Hand&amp;sa=D&amp;sntz=1&amp;usg=AFQjCNEjoGp7oconXGogKnPxpbA635eTWQ</a></p><p>Gerardo</p>
<p>Hi <a href="http://www.instructables.com/member/bocabearing" rel="nofollow">bocabearing</a> , i cannot find the full programming code for both the 3D printed hand and the glove on the site u provided above.<br>Can you please help how you do the wireless communication?</p>
Hi jesher777,<br><br>The link that I provided directs you a page filled with different parts that I went through for the project. <br><br>Part 5 includes the first code that I used. http://bocabearingsworkshop.blogspot.com/2015/05/3d-printed-robotic-hand-part-5_15.html<br><br>Part 7 includes a code that I used that didn't require the use of a servo shield for the Arduino. Instead, I just used a breadboard to provide an external power source to the servos.<br>http://bocabearingsworkshop.blogspot.com/2015/11/3d-printed-robotic-hand-part-7-last.html<br><br>Part 8 includes the robotic hand's schematic that is to be used for the code from part 7.<br>http://bocabearingsworkshop.blogspot.com/2016/01/3d-printed-robotic-hand-part-8-wiring.html
<p>Hey Gabry,</p><p>Why didn&acute;t you use the LilyPad board on the reciever hand instead on the UNO? </p><p>ty.</p>
Hi AndresM41, I used the Arduino UNO because there are shields made for it that are convenient to do different things, in my case I used two shields that allow to connect the servomotors and the XBee module to the Arduino UNO. Also Arduino UNO has a higher current output and I think the LilyPad couldn't manage to control 5 servomotors.<br>Maybe it's possible, but there is still the problem of connecting the servomotors to it, it's not so handy.
<p>can i use 5 servo without any shield</p>
<p>Yes, but any servo shield help you connecting the 5 servos to the Arduino board, I suggest to use one because it's more convenient.</p>
<p>Replay me as soon as possible</p>
I am not sure where to find the item on step 4 picture 5 and I am not entirely sure on how to assemble it with the sheild and arduino. If I could get a better explanation that would be great
<p>That is the Robot Shield I bought from futurashop: <a href="https://www.futurashop.it/shield-per-arduspiderin-ardubipe-e-ardufilippo-8190-robotshield">https://www.futurashop.it/shield-per-arduspiderin-...</a></p><p>If you can't find that you can buy any other servo motor shield for Arduino.</p><p>The shields for Arduino simply fits on the two row of pins that Arduino UNO has on its bard. You have to know a little about the circuit of the shield before use them and start to programming :)</p>
<p>Hey Gabry, thanks for your info, but i was wondering what did you use to code both of your xbee? And did you use a dongle?</p><p>Thanks, hope to hear you soon.</p>
<p>You don't need to program the XBee modules if you have the Series 1. Anyway it's possible to program them by an XBee adapter and downloading its tool (X-CTU): http://www.digi.com/support/productdetail?pid=3352&amp;osvid=57&amp;type=utilities</p>
<p>Hi Gabry,</p><p>I like your design. I was wondering whether it could be adapted to replicate full limb movement using additional bend sensors (such as lower arm rotation and elbow bend, shoulder movement? )</p>
<p>Yes it's possible :) but you have to consider the number of analog input pins of the Arduino Lilypad, I think you would need different boards for a project like that.</p>
What did you use for connecting the different joints of the hand together?
<p>the fingers are made of wood, I jointed them with a simple screw and nut. Then I used some fishing wire to connect the top of the finger to the servomotor</p>
does it must be a Xbee module because its really cheap<br>

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Bio: Hi, I'm Gabry295, and I like doing electronic things, even if at the moment I have only one Instructable :) I like robots and everything ... More »
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