Sprocket for mobile robot track drive

A drive sprocket for a mobile robot driven by a track, comprising:

• a hub having a central axis;
• a circumferential rim being connected to the hub by a plurality of radial spokes extending from the hub to the rim;
• each of the plurality of radial spokes includes a fin formed on a radially outer portion thereof, the fin comprises upper and lower sides parallel to the central axis and a pair of opposing lateral sides that extend from the upper side to the lower side, each of the upper sides includes a width that is greater than a transverse width of teeth engaging openings in the track but less than a transverse width of the track;
• the lower side is wider than the upper side such that each opposing lateral side forms an angle F with a normal to the lower side, wherein the normal lies in a plane of the fin and the angle F is in a range of ten to fifty degrees;
• and
• a plurality of teeth extending radially outward from the rim and being configured for engaging teeth-engaging openings in the tracks, wherein each of said fin is disposed at a circumferential location of a respective one of the plurality of teeth,
• wherein the circumferential rim includes a plurality of circumferential areas, wherein each of the plurality of the circumferential areas is situated between a pair of the plurality of teeth and includes a radially outermost surface, and wherein a width of each of the plurality of circumferential area increases radially inwardly from the radially outermost surface.

A drive sprocket for a mobile robot driven by a pair of parallel tracks, comprising:

• a hub having a central axis;
• a circumferential rim being connected to the hub by a plurality of radial spokes extending from the hub to the rim;
• each of the plurality of spokes includes a fin formed on a radially outer portion thereof, the fin is symmetric about a plane that is normal to the central axis and bisects the rim, the fin comprises upper and lower sides parallel to the central axis and a pair of opposing lateral sides of equal length that extend from the upper side to the lower side, each of the upper sides includes a width that is less than half the transverse width of the track;
• wherein the lower side is wider than the upper side such that each opposing lateral side forms an angle F with a normal to the lower side, and wherein the normal lies in a plane of the fin and the angle F is in a range of twenty to forty degrees;
• and
• a plurality of teeth extending radially outward from the rim and being configured for engaging teeth-engaging openings in the tracks, wherein each fin is disposed at a circumferential location of a respective one of the plurality of teeth,
• wherein the circumferential rim includes a plurality of circumferential areas, wherein each of the plurality of the circumferential areas is situated between a pair of the plurality of teeth and includes a radially outermost surface, and wherein a width of each of the plurality of circumferential area increases radially inwardly from the radially outermost surface.