Motion analysis of snake

http://www.qldzoo.com/snakes-move/

First of all, there are two kind of snake movement. Of course some snake move by sidewinding motion which is slide and jump to side or Caterpillar movement which is movement like caterpillar according to their size. But most snake use Serpentine movement and Concertina movement when they move forward. Serpentine movement is like upper diagram. Red part push the ground or obstacles to get reaction forces. Reaction forces form vector sum and resultant force make snake move forward.

When we see serpentine movement as 3D graphics, only force generation part contact to the ground and rest of part is lifted.

Second moving method is concertina movement.

http://www.qldzoo.com/snakes-move/

This movement is pushing and pulling. Snake push their frontal body as support with tail part. After that frontal body contact to the ground and pull the tail part to move forward. When snake climb up the pole, it use two motion simultaneously.

First snake push up frontal body by Serpentine movement and coil the pole using their frontal body. Then it pull their tail part as holding the pole like concertina movement, Snake coil the pole using their tail part and push up frontal body again. Climbing motion consist of holding and moving. Important part is holding motion. It generates holding force based on skin and coiling force.