A medical robotic device comprising: (a) a first elongate device body comprising first, second and third motors; (b) a second elongate device body coupled to a distal end of the first elongate device body; (c) a first driveshaft disposed through the second elongate device body and operably coupled to the first motor; (d) a second driveshaft disposed through the second elongate device body and operably coupled to the second motor, the second driveshaft operably coupled at a distal end to a first bevel gear; (e) a third driveshaft operably coupled to the third motor, the third driveshaft operably coupled at a distal end to a second bevel gear, wherein the first driveshaft is rotatably disposed within and being radially concentric with the third driveshaft, and wherein the third driveshaft is rotatably disposed within and being radially concentric with the second driveshaft; (f) a shoulder joint comprising: (i) a differential yoke rotationally coupled to the first driveshaft, the differential yoke comprising a yoke body and a yoke lumen defined in the differential yoke, wherein the lumen has a longitudinal axis that is transverse to a longitudinal axis of the yoke body; (ii) a dual shaft rotatably disposed within the yoke lumen, the dual shaft comprising: a rotational shaft rotatably disposed within the yoke lumen, the rotational shaft rotationally coupled to the first bevel gear; and an extension shaft extending from the rotational shaft such that a longitudinal axis of the extension shaft is transverse to a longitudinal axis of the rotational shaft; and (iii) an output body rotatably disposed over the extension shaft wherein the output body is operably coupled to the second bevel gear; and; (g) an arm operably coupled to the output body. (a) a first elongate device body comprising first, second and third motors; (b) a second elongate device body coupled to a distal end of the first elongate device body; (c) a first driveshaft disposed through the second elongate device body and operably coupled to the first motor; (d) a second driveshaft disposed through the second elongate device body and operably coupled to the second motor, the second driveshaft operably coupled at a distal end to a first bevel gear; (e) a third driveshaft operably coupled to the third motor, the third driveshaft operably coupled at a distal end to a second bevel gear, wherein the first driveshaft is rotatably disposed within and being radially concentric with the third driveshaft, and wherein the third driveshaft is rotatably disposed within and being radially concentric with the second driveshaft; (f) a shoulder joint comprising: (i) a differential yoke rotationally coupled to the first driveshaft, the differential yoke comprising a yoke body and a yoke lumen defined in the differential yoke, wherein the lumen has a longitudinal axis that is transverse to a longitudinal axis of the yoke body; (ii) a dual shaft rotatably disposed within the yoke lumen, the dual shaft comprising: a rotational shaft rotatably disposed within the yoke lumen, the rotational shaft rotationally coupled to the first bevel gear; and an extension shaft extending from the rotational shaft such that a longitudinal axis of the extension shaft is transverse to a longitudinal axis of the rotational shaft; and (iii) an output body rotatably disposed over the extension shaft wherein the output body is operably coupled to the second bevel gear; and; (i) a differential yoke rotationally coupled to the first driveshaft, the differential yoke comprising a yoke body and a yoke lumen defined in the differential yoke, wherein the lumen has a longitudinal axis that is transverse to a longitudinal axis of the yoke body; (ii) a dual shaft rotatably disposed within the yoke lumen, the dual shaft comprising: a rotational shaft rotatably disposed within the yoke lumen, the rotational shaft rotationally coupled to the first bevel gear; and an extension shaft extending from the rotational shaft such that a longitudinal axis of the extension shaft is transverse to a longitudinal axis of the rotational shaft; and a rotational shaft rotatably disposed within the yoke lumen, the rotational shaft rotationally coupled to the first bevel gear; and an extension shaft extending from the rotational shaft such that a longitudinal axis of the extension shaft is transverse to a longitudinal axis of the rotational shaft; and (iii) an output body rotatably disposed over the extension shaft wherein the output body is operably coupled to the second bevel gear; and; (g) an arm operably coupled to the output body.