Pressure on the tube was measured with a pressure gauge, and the external torque acting on the joint was calculated based on digital pictures taken of the model. Later, he constructed a more complex model with multiple joints, tested its strength and flexibility, and also compared it to other forms of robotic joints and rotary actuators. Later, he experimented with adding additional tubes to a joint. The author presented a table of properties of the hydraulic joint, which included pacifications of the tube and the flexible beam, as well as Young modulus for both.
Also, he gave the pressure measured in relation to the angle of the joint and torque exerted, and the energy efficiency of the joint given several different load weights. The data was given in tables and charts. The author was pleased to find that experiments agreed with the calculated results. He also derived a new equation for joints using the tube modules as joints. It is amazing what new technologies we can discover by simply observing nature.
Spiders are very efficient movers and it stands to reason that the design of their legs plays a major role in their success in the wild. Makes sense to develop robotics based on these highly efficient appendages.