Introduction: DIY $200 Robotic Hand - Arduino Project
I designed and built this robotic hand and the controller for less than $200. The fingers and thumb are controlled by servo motors. The first video shows the hand in action. The second video shows how to make the hand.
Here is Part 2: DIY $200 Robotic Hand Part 2: The Controller
Visit my website for an Arduino sketch to test the hand: http://www.SurfingReality.com
Parts you will need:
1 bicycle chain
1 spool SpiderWire fishing line (It's made with Dyneema, and I used 3 strands of 65 pound test line, which I made into a rope for each finger)
see my video for making rope with this fishing line: https://www.instructables.com/id/How-to-Make-the-Worlds-Strongest-Rope/
1 Arduino (I used the Uno R3)
1 Maker Shield (Maker Shed)
1 mini breadboard (Maker Shed)
4 servo motors
1 AA battery pack for 6 AAs
14 extension springs (A 200pc. Spring Assortment from Harbor Freight Tools had all the springs I needed for the hand and the controller. You can vary the length and spring wire diameter to adjust fingers)
11 #6-32 x 1/2" L machine screws (most hardware from Home Depot)
15 #6-32 x 3/4" L machine screws
3 #6-32 x 1 1/4" L machine screws
1 #6-32 x 1 1/2" L machine screw
2 #10-24 x 1 1/4" L machine screws (Stove Bolt Assortment from Harbor Freight Tools)
4 machine screws that will fit into the holes on the servo's horn. (~0.075" diameter)
6 2" L x 1/2" ID x 15/16" OD #10-24 eye bolts (Eye Bolt Assortment from Harbor Freight Tools)
41 #6-32 nuts
17 #10-24 nuts
14 washers 1/2" OD
8 washers 3/8" OD
5 rubber washers 1/2" OD 1/8" thick
6 tapered rubber feet
3 1/2" snap studs (Fabric Store)
1 small sheet of lexan 1/8" (.1" actual) (Home Depot)
4 tie down brackets (Home Depot)

Participated in the
Epilog Challenge V
14 Comments
2 years ago on Introduction
Nicely done aaronthomen.
7 years ago
Would it be possible to make the hand do a specific motion on something such as a timer or a clock without having an actual hand control it?
9 years ago on Introduction
So is it possible to have two free "hands" ( one robotic and one real) I am going to build a robotic hand for my friend as a birthday present (he only has 1 hand) and I would like him to be able to control two hands at once. If not then it is just a longer arm. Thank you for your time.
Reply 9 years ago on Introduction
I have connected this robotic hand to my EEG machine. I used the electrodes to detect the muscle impulses in my forearm. I didn't spend a lot of time on it, and individual finger control was tricky (signal interference from other muscles), but it did work. Another option would be to trigger the whole hand to close using the movement of another body part (using flex sensors). Fine motor control will be very difficult, unless your friend is willing to let you surgically implant electrodes, and if he's a good enough friend he won't have a problem with this.
Reply 9 years ago on Introduction
Thank you for your time, I would love to see some future projects. I am going to modify this project though… I am going ("try") to make the whole contraption wireless from a single Arduino. Keep up the hard work with your projects.
10 years ago on Introduction
Love this and plan to build it!
Don't see the pot's in the list. Can you list the specification?
Where did you get the knobs for the pots?
Reply 10 years ago on Introduction
The potentiometers are listed in the parts list of part 2:
https://www.instructables.com/id/DIY-200-Robotic-Hand-Part-2-The-Controller-A/
The resistance of each pot makes no difference (I used 2 10Ks, 1 50K, and 1 100K and they all work the same - the Arduino doesn't care)
I got them from Radio Shack, along with the knobs.
Reply 10 years ago on Introduction
The potentiometers are listed in the parts list of part 2: https://www.instructables.com/id/DIY-200-Robotic-Hand-Part-2-The-Controller-A/
The resistance of each pot makes no difference (I used 2 10Ks, 1 50K, and 1 100K and they all work the same - the Arduino doesn't care)
I got them from Radio Shack, along with the knobs.
10 years ago on Introduction
Excellent work.
I think you're missing the mini breadboard on the list also.
I'm assuming this is it:
http://www.makershed.com/Mini_Breadboards_p/mkkn1.htm
Reply 10 years ago on Introduction
Thanks! I added the mini breadboard.
10 years ago on Introduction
GREAT WORK ! Love the Video instructions - Clear, Simple, straightforward .
Reply 10 years ago on Introduction
Thank you!
10 years ago on Introduction
I'm guessing that is bicyle chain for the fingers? I wasn't listed in the parts list. A fantastic build none the less very impressed!
Reply 10 years ago on Introduction
I added the bicycle chain to the parts list. Thanks for your comment!