This is an example of the sort of documentation we'll be expecting from your investigations...
This is just one small part of the investigation, it is only about one investigation in to one type of grip which is only one part of the project.
You need to do this as you go along, adding a bit each day so that you don't end up with a huge write up at the end.
Crab Claw grip
I was investigating the grip part of the arm.
Rather than move two separate grippers I wondered if it would be easier to move just one, like a crab claw.
One side of the grip would be fixed and the other pivot, driven by a syringe to open and close. A syringe can provide a push and a pull so it can open and close the grip.
First attempt
I hot-glued the plunger of the syringe to the moving part of the claw. This did not work.
As the claw pivoted the syringe had to turn because the end of the plunger was fixed rigidly to the cardboard.
The plunger moves in a straight line while the part of the card it is attached to moves around in an arc (part of a circle).
I needed to allow for this movement.
Second Attempt
By drilling a hole in the plunger and using a brass paper fastener to attach the syringe to the card the claw could rotate as the plunger extended.
This arrangement worked well. I could open and close the claw by blowing and sucking on the syringe.
I connected a second syringe with a piece of tube to create a pneumatic control for the claw.
I then attached the syringe to the stationary part of the claw so that I didn't have to hold the two parts together. I cut a slot for one of the tabs on the syringe body and then hot-glued it in place. The hot glue forms a very strong bond.
The syringe still needed to turn a little bit but I'm sure this can be managed by including some flexibility in the mounting between the syringe and the fixed part of the claw.
This is just one small part of the investigation, it is only about one investigation in to one type of grip which is only one part of the project.
You need to do this as you go along, adding a bit each day so that you don't end up with a huge write up at the end.
Crab Claw gripI was investigating the grip part of the arm.
Rather than move two separate grippers I wondered if it would be easier to move just one, like a crab claw.
One side of the grip would be fixed and the other pivot, driven by a syringe to open and close. A syringe can provide a push and a pull so it can open and close the grip.
First attempt
I hot-glued the plunger of the syringe to the moving part of the claw. This did not work.As the claw pivoted the syringe had to turn because the end of the plunger was fixed rigidly to the cardboard.
The plunger moves in a straight line while the part of the card it is attached to moves around in an arc (part of a circle).
I needed to allow for this movement.
Second Attempt
By drilling a hole in the plunger and using a brass paper fastener to attach the syringe to the card the claw could rotate as the plunger extended.
This arrangement worked well. I could open and close the claw by blowing and sucking on the syringe.
I connected a second syringe with a piece of tube to create a pneumatic control for the claw.
I then attached the syringe to the stationary part of the claw so that I didn't have to hold the two parts together. I cut a slot for one of the tabs on the syringe body and then hot-glued it in place. The hot glue forms a very strong bond.The syringe still needed to turn a little bit but I'm sure this can be managed by including some flexibility in the mounting between the syringe and the fixed part of the claw.
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