Firestone Airstroke solar tracker actuator

Airstroke actuators from Firestone provide a compact and easy way to continuously orient a solar tracker’s payload towards the sun to optimise the amount of energy produced. The rubber and fabric actuators can be used to solve the problem of stationary solar collection panels becoming inefficient as the sun shifts from a 90° angle to the panels.

Inflated or deflated by fixed or mobile compressed air (typically 7 bar), the actuators move photovoltaic systems to minimise an angle of incidence between the incoming sunlight and a photovoltaic array. Alternatively, an actuation alternative uses the expansion and contraction of Freon gas as it is heated and cooled within the actuators to extend and retract them and change the angle of the collection panels.

Since there are no seals sliding against exposed surfaces, the air springs can often survive abrasive and corrosive environments. They are identical in construction to the airbags used in truck and train suspension, so they are very tough. In addition to having no internal rods of seals to wear, unlike conventional metal cylinders, they have the ability to rotate through an angle without a clevis.

The ability to bend with load (and to tolerate high side loadings) means the air springs are easy to install in compact spaces and will perform where rigid alternatives would break or wear. Sizes are available from 80 mm to more than nearly 1000 mm in diameter, in single, double and triple convolutions. No lubrication is required and the lack of seals means lack of friction and jerkiness in operation.