Sovella table design 2

this is a design inspired by the gas springs idea but a bit different one. the table uses a cross linkage and a air tube to push the cross link horizontally. the normal foot operated air pumps can also be used. there will be a permanent tube that will be connecting the pumps and the air tubes. the table is not only varies in height but also in length the position of the extra platform is completely controlled by a small pin. there can be 2 positions of the pin one will lock the extra portion to the main top and the other will let it be at the downward position. the force calculations for the table to move. the air pump has to compress the normal air by 15times(i.e 1atm of atmosphere air needs to get to a pressure of 15atm) which is normally done by the pumps and the radius of the tube has to be 3cm. this will help the pump to move the table weight of 500kg at the lowest position and as the table top goes up the amount of force need not be that much and the height of the table can be adjusted by simply removing some weight over the top of the table. this above calculation is for when the maximum weight on the table top is 500kg and at the lowest position. the values change as the weight on the top changes. the user need not pump in air every time he needs to rise the height but just simply removing some weight from the table.