this really deserved its own thread as it can be used for other applications than scoring for the air soft much warrior bots. I will include pictures , drawings and links.
This force-sensing resistor (FSR) from Interlink Electronics is a passive component that acts as a variable resistor, with resistance decreasing in response to increasing applied force, which makes it easy to add a touch interface to your project or create a robot with much more sophisticated tactile senses than are possible with simple lever switches. The polymer thick film (PFT) device is optimized for use in human touch control of electronic devices and can sense an applied force anywhere in the active area ranging from a few dozen grams to over 10 kg (22 lb).
In our tests, the resistance exceeded 1 M? with no applied pressure and dropped to a clearly detectable and very stable 50 k? with a 20 g weight placed on it. Pushing on the pad as hard as possible dropped the resistance to around 200 ?. This resistance range is well suited to work directly with the internal pull-ups of many microcontrollers such as AVRs and PICs. The FSR was responsive enough and sensitive enough to distinctly pick up light, rapid finger tap, and it was even able to pick up the vibrations of a small vibration motor placed on it on the motor's side.
Other robots from Synthiam community

Bhouston's My Inmoov's New Base

Steve's Meet Aegis

I like it.
Iwill try to look for the link,i have 3 different types to compare them,and been awhile since i was trying them out for my biped design by lynxmotion.

this is close to the design only making it a lot lot better