Robotic arm with 7 servos
Description
A little video:
youtube.com/watch?v=gfsLu1iuLRg
More about the electronics and other info at:
jjshortcut.wordpress.com/2010/08/17/multiply-the-robotic-arm-and-electronics/
About the mechanics:
jjshortcut.wordpress.com/2010/04/19/my-mini-servo-grippers-and-completed-robotic-arm/
Instructions
The base is made of one servo with 12mm spacers with m3 screw tread in it and some washers. The bottom and top plate are connected with 45mm spacers and connected with m3 screws which are sunk in the wood. The servo horn is connected with some small screws like 2x10mm (or 1,5x10mm) to the servoplate.
The underarms are connected with 2x10mm (or 1,5x10mm) screws to the servohorns and the servo itself is connected with m3 nuts and bolts to the servomountplates. the servomountplates are stuck in the servoplate with a bit of a press fit. Also u could use some glue for extra support.
The upper arms are connected on the servo with 15mm spacers with m3 screw tread in it, as you can see in the pictures.
The wrist is also connected by a press fit and some long m3x30 nuts and bolts to secure the mini servo.
For more support to lift something you can add a 45mm m3 spacer between the 2 servomountplates and a 15mm m3 spacer between the upperarm parts. Then you could attach a spring (or two) between them.
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Hi friend
I make " handful " but i don't know how to make arm, or rack.
I finished this -> http://jjshortcut.files.wordpr...
But not other things .
How you can post a drawing there or on your site, i following you there and also there jjshortcut.com
I am making on of these on my laser for a fellow Thingiverse reader and was curious to where people get the hardboard for these projects?
Hi,
I've build one and you can read about it here: http://geekswithblogs.net/kobu...
I'm now working on the software to control it and plan to blog more about it.
Big thanks to jjshortcut for this awesome design!
Hi I was wondering if you had burnt out any servos while testing/building this? A couple of my motors were making a faint buzzing sound while not in motion which is apparently a sign for binding. I didn't think much of it until one of the bottom servos (the two at the top of the rotating plate) started smoking. I don't understand what caused it to bind and if this is a problem that will keep happening. The top of the arm is quite top heavy and the movement of the arm is pretty jerky. When I try to get the arm to point all the way up then it's weight causes it to push to one side. Is the servo burning out a precursor to a problem that will keep happening? Any advice on this problem would be greatly appreciated because I am pretty stuck right now. Thanks!
Is the chasis made of cardboard? If not, can you pleases tell me, and give me measurements to make it? :'(
How many servos will I need? Also, I live in the United States, so is there any alternative servo I could use?
Thanks :-D
Hello,
I was wondering how I would attach the gripper and would it be remote controlled too? :'(
What are bearings and spacers?
Also, Please say it is remote controlled and if so how do I make the remote control. :'(
Will this robot arm be programmed with a remote control, and if so how do I control the arm and gripper/hand. Also, what and where is a miniservo?
Thank You.
Hello again, I have been working on your arm and it is coming along nicely. An issue I have run into is I am unsure of how to attach the other part of the elbow (the side that doesn't have a servo). I saw in your video that you had some black piece there, and I was wondering what those pieces are and how you did that. I saw that you also used that same thing on the wrist. I attached a photo of how far I am minus the gripper.
I was also wondering where the small circular piece needs to go because I don't want to overlook what could be an important part. I attached a photo of it. Thank you so much once again for all your help!
I am a little confused as to what you mean to do with the circular piece. On the fifth picture it shows a different looking piece so does that mean that I should print the piece out on a reprap because laser cut only does one layer?
Also on the part of the robot where you attach the elbow servo and wrist servo to the arm and hand I was wondering what you do to the other side that is not directly attached to a servo that is on the backside of the servo that will still be able to rotate. I saw that in your video that you had tw
o black pieces but I can't see what they are from the angle. I attached a photo of the side that attaches directly to the servo, but I was just wondering how to attach the other side of the piece to the arm without a servo??
Hi, the 5th picture of above shows the circular part, this is the bearing thingy which is on the back of the servo. It's actually a bearing together with the hole in the long part. I taped it to the back of the servo with double sided tape. The "bearing" piece has to be made out of plastic actually otherwise it wil not work that good. Hope that helps!
hai friend,very nice work, i'm also starting the work of thi arm. i'm planing to buy servos of 3KG is that sufficient??? i'm using pvc sheet of 2mm.
Hi great project! I want to make a robotic arm for a project at school and I have read though your wordpress and have watched your video. I was wondering because I see that you are using what looks like a normal RC transmitter in your project but you have 7 servos hooked up. Did you use connect some of them to the same channel with splicing? I was wondering because I have a five channel transmitter and was wondering if that would work. Also I saw that most of the servos you used are standard. But, the servos you used are not sold in the US sadly, but I want to use something similar or with more power to lift heavier objects. Would you recommend using high power 90 degree servos for the claw and such and 180 degree servos for the rotating base? I was also wondering where you got your 15mm and 45mm spacers from, or could I just use a combination of 5mm and 10mm nylon or aluminum spacers to get the space desired? Sorry for all the questions. I am a beginner to robotics and don't really know where to start. Thanks!
For the demo video I used a rc transmitter yes, I connected the 2 servos of the 'elbow' of the robot to one channel. So the elbow actually only needs one control signal. With your transmitter you can only control 5 servo's...
For the servo's you can use just regular servo's you can find, it doesn't matter that much. But for some more heavy lifting you should need stronger ones. And for the gripper I used just normal servo's, 180 deg. I do not think it makes a lot difference 90 or 180, it doensn't use the whiole range o
f 180, but it might be that 90 deg. is to less.. Not sure.
For the spacers you can use anything, I just like the nice metal or plastic spacers.
HI cool project what size sheet is the Whole robotic arm drawing on ????????????? :) :)
To JJ
I am in my final year BTECH in electronics and communication . This is my Final project .Have done it only because of ur support through thingiverse.Hope u like it.
I have used part steel and part wood for weight consideratons and also have attached a spring.I am using a 16servo usb controller
i made de arm but i have a problem the arm is so heavy, the arm fall , i am change servos for a 13kg/cm stall torque, is beter but not solve a problem , im use 6mm acrylic board and a power suply if 5v and 4 A, i have some pictures, i think the acrylic board is much heavy for this project. what you think about
thanks and sorry for a bad english
hi again,
i have finished my hardware part ... i need to know how to reverse the servos,as the servo motors rotate only in one direction
thank u
sumanta
Would you be able to upload .eps / .svg files to accompany the .dxf file? There are more free tools that can work with SVG and Ponoko accepts it as a format for laser cutting. Thanks regardless though, it's a cool design and I really like the gripper.
hello;
i am making one of this with 3mm ss.can u suggest a possible way to connect the upper right wrist to the upper right arm.
as the left side of the upper arm is connected with a servo to the left wrist .....
i am out of ideas here ...
thank u
hello,
I made one out of ABS sheet 3mm. it works fine.
I changed a piece and added a GP2D12.
Programmed in vb. It can play against an AL5B from Lynxmotion.
all is handmade :(
What scale is the dwf file set to? I'm trying to print it full scale and can't seem to be able to do it.
hi,i work in a robotic arm with you files and instruction, but the mechanic parts made in acrylic plate, and i use a circuit if a PIC 16F628A for control movements of robot arm, soon i have photos and video to post for you thank for your post
sorry for bad english, i from brazil adn english is not my natural language
This looks very cool. What kind of weight can it lift? Are all of the joints just using plastic spacers to reduce friction?
I made one of these out of aluminum and it works pretty good (except for my code moving it) I have a video and some more info about it here http://www.robhopeless.com/
License
More from jjshortcut
i was thinking you could make this but use hydraulics(syringes with oil and tubes) that are actuated by servos, that way it reduces the weight of the arm that needs to be lifted and it would just be cool.