Plz help9 with intro to comp architecture

9. am designing an autonomous robot to avoid obstacles using six touch sensors and to detect an infrared beacon with six infrared sensors. 9(a) polling (the cPU asks devices one by one if they require attention) or interrupt (an Should I use attention, request signal to the cPU) for i/o device, when requiring CPU's sends a interrupt avoiding the obstacles? Explain. [2 marks] 9(b) Should I use polling or interrupt for detecting the beacon? Explain. [2 marks]