Cardboard Robotics: Building a Desktop Robotic Arm

[Sponson]

Hey all! Undergrad in M.Eng here, building a desktop robotic arm (<12 inches tall, arduino board) for a personal project. I've been looking at materials, and aluminum and wood are both doable, but if possible I'd rather use a lighter material that I can cut without machines, such as a strong cardboard or cardstock that could be cut in sheets and designed to be structurally secure. Does anyone have experience with these materials? Any recommendations for what type to buy or where?

 

[BvU]

Hey Sponson ! Ever consider using a Lego robot arm ?

 

[Sponson]

Hey Sponson ! Ever consider using a Lego robot arm ?

Well, Now I certainly am! I have bins of legos sitting in the basement unused, but would they be able to attach to servo's and other components very easily?

 

[berkeman]

Hey all! Undergrad in M.Eng here, building a desktop robotic arm (<12 inches tall, arduino board) for a personal project. I've been looking at materials, and aluminum and wood are both doable, but if possible I'd rather use a lighter material that I can cut without machines, such as a strong cardboard or cardstock that could be cut in sheets and designed to be structurally secure. Does anyone have experience with these materials? Any recommendations for what type to buy or where?

As an ME, you may be using Foam Core material sheets for some of your models and mock-ups in the future. It's a much more stable material than just cardboard...

https://www.superlinkstore.com/assets/uploads/2016/04/whit-paper-foam-core-board-copy.jpg

 

[BvU]

Well, Now I certainly am! I have bins of legos sitting in the basement unused, but would they be able to attach to servo's and other components very easily?

I was thinking of the product "Lego Robot arm" . I'm sure Lego is keen on selling their controller stuff instead of your arduino, but perhaps you can find out what's needed to drive the thing.

The video nicely shows some limitations (e.g. vibration after sudden stop) that you might improve upon with better hardware and better control software !

But I see a search for "robotic arm arduino" gives lots of hits too

 

[JBA]

I have used foam board for many prototypes with low loads. For items thicker than the basic 1/8" board it is best to use the 1/8" board and laminate it to the thickness you require. For substantially stronger pieces, using simple thin plastic sheet laminated on both outside faces of the foam board assembly adds an amazing amount of strength to the structure (I buy the standard plastic sheet signs sold at the local hardware stores in my area for material because this material is very easy to cut). For pivots or bolted connections you need to insert and glue pieces of metal tube through the sheet structure to act as bushings (12" lengths of aluminum or brass ones in various diameters are also available at my local hardware stores).

 

[Sponson]

I have used foam board for many prototypes with low loads. For items thicker than the basic 1/8" board it is best to use the 1/8" board and laminate it to the thickness you require. For substantially stronger pieces, using simple thin plastic sheet laminated on both outside faces of the foam board assembly adds an amazing amount of strength to the structure (I buy the standard plastic sheet signs sold at the local hardware stores in my area for material because this material is very easy to cut). For pivots or bolted connections you need to insert and glue pieces of metal tube through the sheet structure to act as bushings (12" lengths of aluminum or brass ones in various diameters are also available at my local hardware stores).

Thank you so much! This is exactly the kind of product I was looking for, because I'd prefer the freedom and experience of manufacturing the parts than constructing it from LEGO or a kit

 

[JBA]

Just as a note on the cutting of foam board, it can be difficult to get a clean edge cut with this material. First, a very sharp cutting blade is required and the foam interior tends to grab on the faces of a cutting blade and tear, which I have discovered can be remedied by repeated applications of a film of "petroleum jelly" on both faces of the cutting blade (as improbable as this may sound).

 

[Sponson]

As an ME, you may be using Foam Core material sheets for some of your models and mock-ups in the future. It's a much more stable material than just cardboard...

View attachment 205100

I've been reading much more into foam and plastic options (probably going to do a plastic-foam sandwich), but foam core distributors I find tend to be from industrial supply quantities or "craft store" display foam board. Should I search for a particular type of foam or am I reading too deeply into material design for this small of a project?

 

[JBA]

The foam board I use is straight from the local crafts store. To my knowledge there are no different grades of this material.

As a new product development engineer for many years, one lesson I learned is that generally by the time you finish a prototype of an item you already know how it could be made better, so don't focus on overbuilding the first one and don't be hesitant to throw that one out and replace it. Prototypes are learning tools.