making a robotic gripper u need following things....
1)some wood's rod and a wood plate
5)2 equal radius gears
6)a pen etc.
Step 1: MAKING..........
now join the wood rods to gears as shown in image.
now make hole in wood plate equal size of motor shaft.
now mount motor on plate.
Step 2: L.....
now mount one gear on motor shaft and another gear on a metal rod and mount that rod on wood plate as shown in fig. this assemble make turning pairs.
now take 2 another rods equal size of turing pairs radius.
now mount these both 2 rods to wood plate as show in fig,these mounted rods must be turning pair.
now take 2 another rod of length 2-3 times of older one.
Now join these rods to another rod as shown in fig.
Step 3: Modifications.....
now add parts in gripper as shown in images........
now your gripper ready for work.