Device for driving a light receiving element to track a light source
A light tracking device comprising first and second support members and at least one light receiving element supported on each support member by one or more resilient flexible beams which deform upon relative translational displacement of the first and second support members. The first and second support members are arranged such that relative translational displacement of the members generates rotational displacement of the element. One or more resilient flexible beams may comprise spiral arms extending from the first to the second support members.
1. A light tracking device comprising:
first and second support members; and
at least one light receiving element supported on each support member by one or more resilient flexible beams which are each folded or curve such that they are each much longer than the direct path between their two anchor points and which elastically deform upon relative translational displacement of the first and second support members,
wherein the first and second support members and the resilient flexible beams are arranged such that relative translational displacement of the support members elastically deforms the resilient flexible beams and generates rotational displacement of the at least one light receiving element.
2. The light tracking device of claim 1 , wherein the one or more resilient flexible beams comprise spiral arms.
3. The light tracking device of claim 1 , wherein the resilient flexible beams are created from a flat component.
4. The light tracking device of claim 1 :
wherein the first and second support members and the resilient flexible beams are arranged such that a relative translational displacement of the support members elastically deforms the resilient flexible beams and generates a rotational displacement of the at least one light receiving element of at least 24 degrees.
5. The light tracking device of claim 4 , wherein the first and second support members and the resilient flexible beams are arranged such that a first relative translational displacement of the support members elastically deforms the resilient flexible beams and generates a rotational displacement of the at least one light receiving element about a first axis, and a second relative translational displacement of the support members elastically deforms the resilient flexible beams and generates a rotational displacement of the at least one light receiving element about a second axis perpendicular to the first axis.
6. The light tracking device of claim 5 , wherein the first relative translational displacement generates a rotational displacement of at least 24 degrees from a centre point, and the second relative translational displacement generates a rotational displacement of at least 60 degrees from a centre point.
7. The light tracking device of claim 4 , wherein the at least one light receiving element comprises plural light receiving elements.
8. The light tracking device of claim 1
wherein the resilient flexible beams and/or the first and second support members are formed from single pieces of sheet material.
9. The light tracking device of claim 8 , wherein the first support member and the one or more resilient flexible beams connected thereto are integral, and the second support member and the one or more resilient flexible beams connected thereto are integral.
10. The light tracking device of claim 8 , wherein each of the single pieces of sheet material consists of spring steel.
11. The light tracking device of claim 1 :
wherein the first and second support members are substantially planar; and
wherein the first support member and the one or more resilient flexible beams connected thereto lie substantially in a first plane, and the second support member and the one or more resilient flexible beams connected thereto lie substantially in a second plane.
12. The light tracking device of claim 11 , wherein the first and second support members are substantially parallel to each other.
13. The light tracking device of claim 12 , wherein the distance between the support members is controlled by at least one passive structural element.
14. The light tracking device of claim 13 , wherein the at least one passive structural element comprises a wire connecting the first and second support members.
15. The light tracking device of claim 11 , further comprising first, second and third actuators respectively configured to control the offset between the first and second support members in first, second and third perpendicular directions.
16. The light tracking device of claim 1 comprising:
a plurality of light receiving elements each supported on each support member by one or more resilient flexible beams which elastically deform upon relative translational displacement of the first and second support members,
wherein the first and second support members and the resilient flexible beams are arranged such that relative translational displacement of the first and second support members elastically deforms the resilient flexible beams and generates substantially the same rotational displacement of each of the plurality of light receiving elements.
17. The light tracking device of claim 16 , wherein the first and second support members are each substantially planar and are substantially parallel to each other.
18. The light tracking device of claim 17 , further comprising first and second actuators respectively configured to control the offset between the first and second support members in first and second perpendicular directions in a plane defined by the first or second support member.
19. The light tracking device of claim 16 , wherein each of the plurality of light receiving elements is a solar concentrating element which concentrates the light, and the light tracking device further comprises at least one photovoltaic cell for each light receiving element positioned at a point where the light is concentrated.