I appreciate your advice hippy, thankyou.
I guess your right about the poll, the main feedback I was after is how to improve?
The movie is in MPEG4 with no sound...
When we get this going I might post an easy to follow "how".
HISTORY:
Oscar was developed as a test of the mechanical, electrical and programming abilities of Glenn Maple and myself.
The name Oscar, (only a recent addition by me) came about by the first sentence ever written by the arm, which was a quote by the Irish-born author of the late nineteenth century, Oscar Wilde. From this point on ‘The arm’ became known as Oscar.
Design:
The design came about after a few hours of research on the Internet. It is mainly taken from a robotic arm called the Lynx 5 Robotic Arm. From this concept I created a simple template for the Perspex.
Materials:
Oscar’s base is made of wood, on top of which sits a second Perspex base. The upper and the lower arm are also made of Perspex. A metal brace is used to support the shoulder. Screws, nuts and bolts are used for joints and support.
Electronics:
The entire arm, consisting of 5 servo motors, and is run using a PICAXE 28X Micro controller. Other electrical materials include, a 6 volt power supply, wire, capacitors, resistors, diodes and connectors.
Time:
The arm was constructed and ran with a basic program in Semester 2, 2006, allowing it to type the alphabet on a computer keyboard. Further improvements to programming were made in Term 2, 2007, including the ability to write words and sentences.
Programming:
In 2006 the program consisted of a set of motor coordinates and pauses. That has now been developed to have all letters, and some other keys as sub routines. This allows any letter to be called upon in any order.
Faults:
Oscar runs well and can complete sentences without more than two or three mistakes. All mistakes are due to miss-presses where Oscar will:
-Press down before the destination of the key is reached,
-Double press a key,
-Miss a key
Cost:
Servos ($16 each) $80
Picaxe 28X and board $50
Other materials $20
-------
$150
Future improvements:
I have tried programming Oscar with a unique speed control program, but this proved to large and clumsy. I may try re-writing this program to get rid of the fast, jerky movement.
Other improvements include making another arm with more abilities, for example, a gripper.
Credits:
Matt O’Neil, Assistant programmer and technician.
Josh, Assistant programmer.
Brian Fitches, Technical backup.
Glenn Maple, Co-production and Co-initial programming.
Lliam Anstey-Sprigg, Design, Co-production, Co-initial programming technician and new
programming.
FUTURE:
My ideas on future design so far are:
-external pots for position feedback
-2 x Home made pressure sensor on top, bottom ,left and right of each main joint.
(these would be wired in series so that top back and bottom front were paired. This would mean that if the joint was trying to pick up something to heavy, the resistance would lower and be read by a PICAXE. Maybe even calculate the weight!)
-GRIPPER! (defiantly a necessity by struggling to find a good, easy, universal design...
Suggestions are welcome!
Lliam