A rear-end transmission device for a robotic surgical manipulator, comprising: a first rotating member connected to a first cable and a second cable , wherein the first cable and the second cable wrap around the first rotating member in opposite directions; a second rotating member connected to a third cable and a fourth cable , wherein the third cable and the fourth cable wrap around the second rotating member in opposite directions; a first pulley assembly including a first movable pulley , wherein each of the first cable and the second cable extends from the first rotating member and rides on the first movable pulley ; a second pulley assembly including a second movable pulley , wherein each of the third cable and the fourth cable extends from the second rotating member and rides on the second movable pulley ; and characterized by comprising: a position adjusting assembly comprising two sliders disposed in parallel and a rotating assembly disposed between the two sliders and meshing both the two sliders , wherein each of the first movable pulley and the second movable pulley is rotatably connected to a respective one of the two sliders ; wherein with a rotation of the rotating assembly , the two sliders move linearly in opposite directions to concurrently adjust positions of the first movable pulley and the second movable pulley , to pull in the first cable and the second cable while releasing the third cable and the fourth cable , or to pull in the third cable and the fourth cable while releasing the first cable and the second cable . a first rotating member connected to a first cable and a second cable , wherein the first cable and the second cable wrap around the first rotating member in opposite directions; a second rotating member connected to a third cable and a fourth cable , wherein the third cable and the fourth cable wrap around the second rotating member in opposite directions; a first pulley assembly including a first movable pulley , wherein each of the first cable and the second cable extends from the first rotating member and rides on the first movable pulley ; a second pulley assembly including a second movable pulley , wherein each of the third cable and the fourth cable extends from the second rotating member and rides on the second movable pulley ; and characterized by comprising: a position adjusting assembly comprising two sliders disposed in parallel and a rotating assembly disposed between the two sliders and meshing both the two sliders , wherein each of the first movable pulley and the second movable pulley is rotatably connected to a respective one of the two sliders ; wherein with a rotation of the rotating assembly , the two sliders move linearly in opposite directions to concurrently adjust positions of the first movable pulley and the second movable pulley , to pull in the first cable and the second cable while releasing the third cable and the fourth cable , or to pull in the third cable and the fourth cable while releasing the first cable and the second cable . a position adjusting assembly comprising two sliders disposed in parallel and a rotating assembly disposed between the two sliders and meshing both the two sliders , wherein each of the first movable pulley and the second movable pulley is rotatably connected to a respective one of the two sliders ; wherein with a rotation of the rotating assembly , the two sliders move linearly in opposite directions to concurrently adjust positions of the first movable pulley and the second movable pulley , to pull in the first cable and the second cable while releasing the third cable and the fourth cable , or to pull in the third cable and the fourth cable while releasing the first cable and the second cable . <EOS>