This the third bot I am posting here. Its not very amazing but still love to post here to get comments about how I can improve it.
*sorry for any unclear pictures
This an electro-magnetic cranewhich works on simple polarity concepts.
There is a servo underneath(Which I have upgraded for continuous rotation) and a dc motor over that.
U can see in this picture:
This setup gives the funcionality of a DOF servo bracket.
I have connected 2 push buttons through a breadboard for the vertical movement.
The horizontal movement is controlled by merely connecting wires to coins. (In the crane, I have attached two nails to the two terminals of servo through wires and coins are conected to the battery so that I can easily change the direction of movement by interchanging the nails.) :P
Here are the breadboard connections:
The picture must have explained it better.!
The electro magnet can be controlled by the on-off switch attached for picking up and dropping items wherever it is supposed to be....
The switch and connection: 
(I didn't have a 9V battery available so clicked without that.. well, the I will stick the battery on the other end of the 'scale' and connect it directly to the switch)
Some more pics:
P.S. -> the wheels are completely manual. they are just sopposed to let the crane move by applying force.
move along fixed axis, pick up, and drop objects. Locomotion in closed range.
- Actuators / output devices: servo modified for continuous rotation, dc motor(90 degree shaft)
- Control method: Semi-autonomous
- Power source: three sources- 4 AA cells, 3 AA cells And a 9V battery
- Sensors / input devices: 2 push-buttons, other simple things
- Target environment: almost every dry place
This is a companion discussion topic for the original entry at https://community.robotshop.com/robots/show/crane-bot