Answer Happy

(6) Time (seconds) 43 4.0 a double gripper. The work cycle consists of the following sequence of activities: A robot performs a loading and unloading operation for a machine tool by means of Sequence Activity Step 1 Robot reaches and picks raw part from incoming conveyor in one performed simultaneously with machining cycle gripper and awaits completion of machining cycle. This activity is Step 2 At completion of previous machining cycle, robot reaches in, retrieves finished part from machine, loads raw part into fixture, and moves a safe distance from machine. Step 3 Machining cycle (automatic) Step 4 performed simultaneously with machining cycle. Robot moves to outgoing conveyor and deposits part. This activity is Step 5 Robot moves back to pick-up position. This activity is performed simultaneously with machining cycle. Steps 1, 4, and 5 are performed simultaneously with the automatic machining cycle. Steps 2 and 3 must be performed sequentially. Every 40 work parts, the minutes to accomplish. 34.0 3.0 2.7 The uptime efficiency of the robot is 97% and the uptime efficiency of the machine assumed not to overlap (ie. if the robot breaks down, the cell will cease to operate, so the machine tool will not have the opportunity to break down and vice versa). Downtime results from electrical and mechanical malfunctions of the robot, machine tool and fixture. Determine the hourly production rate (taking into account the lost time due to tool changes and the uptime efficiency). The company is considering installing two machine tools. The existing double gripper robot would load and unload both machines from the same incoming and outgoing conveyors and be placed equidistant from each machine. The machining cycles would be staggered so the robot would be servicing only one machine at a time. (7 marks) Determine the overall hourly production rate for the two machine system described, assume the activity times and efficiencies remain the same. (3 marks)