
	Trending ▼ ICSE CBSE 10th ISC CBSE 12th CTET GATE UGC NET Vestibulares ResFinder

GCE JAN 2008 : (A2 3) Systems and Control in Product Design

16 pages, 40 questions, 0 questions with responses, 0 total responses,

	gce	+Fave Message
	Profile Timeline Uploads Q & A

Home > gce >

Instantly get Model Answers to questions on this ResPaper. Try now!
NEW ResPaper Exclusive!

Formatting page ...

ADVANCED General Certificate of Education January 2008 Technology and Design assessing Unit 6 Systems and Control in Product Design A2V31 Assessment Unit A2 3 [A2V31] TUESDAY 8 JANUARY, AFTERNOON TIME 2 hours 30 minutes. INSTRUCTIONS TO CANDIDATES Write your Centre Number and Candidate Number on the Answer Booklet provided and on the A3 pro forma answer pages provided. Answer three questions. Answer the one question in Section A and either the two questions in Section B or the two questions in Section C. Answers to Questions 1(a)(v) or 1(b)(v) and Question 5(b)(ii) should be made on the A3 pro forma answer pages provided. INFORMATION FOR CANDIDATES The total mark for this paper is 80, including a maximum of 4 marks for quality of written communication. Figures in brackets printed down the right-hand side of pages indicate the marks awarded to each question or part question. At the conclusion of the examination, attach the A3 pro forma answer pages securely to the Answer Booklet with the treasury tag supplied. You are provided with an insert sheet for Questions 1(a) or 1(b). Do not write your answers on this insert. A materials data sheet is provided. A2V3W8 3220 Section A This question is compulsory. You are advised to spend 1 hour and 15 minutes on this section. You are required to answer either 1(a) or 1(b). For candidates studying Electronic and Microelectronic control systems answer part (a) using the pro forma (answer 1(a)(v)) and an answer booklet. 1 (a) In a ten pin bowling game, control systems are used to display information, to clear the lane of any fallen pins, to collect pins, and reset them ready for play. Fig. 1(a) shows a control system which begins the following sequence after the player throws their first bowl. The pin distributor lowers to collect any standing pins and then is raised so that the sweep will push any fallen pins into the pin pit. The pins are moved along on to the elevator. Once they reach the top of the elevator they go down a chute on to one of two conveyor belts. The conveyor belts carry the pins and place them into each of the pin holders. Once fully loaded, the pin holders pivot turning the bowling pins upright before they are lowered on to the lane. (i) Suggest a suitable wood for the pins and briefly outline two main reasons why your choice would be suitable. [3] (ii) Briefly outline how these wooden pins would be manufactured in batches. [2] (iii) Suggest a suitable metal for the sweeper arm and briefly outline how the profile would be achieved. [2] (iv) Using annotated sketches briefly outline two alternative methods that will detect a player making a foot fault. [4] A2V3W8 3220 2 [Turn over (v) On the pro forma provided use Electronic and Microelectronic circuit diagrams with annotation to produce a viable solution that will fulfil each of the specified points stated below. (N.B. All brackets, housings, screws, nuts and bolts are not required) Design a circuit that detects the first bowl and generates a pulse when the bowl is approaching the pins. Use this signal to trigger a circuit that energises the dc motor powering the elevator. The motor is to run continuously during the period of play. [6] After a throw each bowl has to be retrieved. At a certain point the bowl and pin are separated. The bowl has to pass through a specially designed ball door which is triggered by a weight sensor. Draw a circuit diagram of a system that detects a ball and outputs a signal which can be used to operate the ball door. [6] The number of pins knocked down after each bowl has been thrown is to be indicated on the Display Board. When a pin is knocked down the appropriate lamp on the Display Board should be illuminated. If a strike occurs i.e. all pins knocked down at one time, then the display should flash ON/OFF repeatedly for 5 seconds. The lamps are 24V, 12 W. Design a circuit to fulfil all of these conditions. A2V3W8 3220 [9] After the 10th bowl is detected the dc motor powering the elevator is to continue running for a period of two minutes and then stop. Design a circuit to do this. [6] 3 [Turn over For candidates studying Pneumatic and Mechanical control systems answer part (b) using the pro forma (answer 1(b)(v)) and an answer booklet. 1 (b) In a ten pin bowling game, control systems are used to display information, to clear the lane of any fallen pins, to collect pins, and reset them ready for play. Fig. 1(b) shows a control system which begins the following sequence after the player throws their first bowl. The pin distributor lowers to collect any standing pins and then is raised so that the sweep will push any fallen pins into the pin pit. The pins are moved along on to the elevator. Once they reach the top of the elevator they go down a chute on to one of two conveyor belts. The conveyor belts carry the pins and place them into each of the pin holders. Once fully loaded, the pin holders pivot turning the bowling pins upright before they are lowered on to the lane. (i) Suggest a suitable wood for the pins and briefly outline two main reasons why your choice would be suitable. [3] (ii) Briefly outline how these wooden pins would be manufactured in batches. [2] (iii) Suggest a suitable metal for the sweeper arm and briefly outline how the profile would be achieved. [2] (iv) Using annotated sketches briefly outline two alternative methods that will detect a player making a foot fault. [4] A2V3W8 3220 4 [Turn over (v) On the pro forma provided use Pneumatic and Mechanical circuit diagrams with annotation to produce a viable solution that will fulfil each of the specified points stated below. (N.B. All brackets, housings, screws, nuts and bolts are not required) Design a gearbox to move the conveyor belt a distance of 6.28 m in order to place all of the pins in the holder in a time of 12 seconds. The input speed is 2400 rpm and the conveyor belt roller has a diameter of 200 mm. (Assume = 3.14 and use gears with teeth between 20 and 120.) Show all calculations and state clearly the number of teeth of each gear. Candidates may ignore the effect of the thickness of the conveyor belt. [9] 3220 Design a mechanism driven by the output shaft of the elevator gearbox that will move the rubber flooring up and down slightly in order to shuffle the pins forward to the elevator. [6] A2V3W8 Design a system that will rotate the sweeper arm through 90 degrees, then move to sweep any fallen or remaining pins into the pit before returning to its original position. [6] Design a system that will detect a pin at the top of the elevator and as a result position the chute over conveyor belt A for a period of time before returning the chute to a position over conveyor belt B. [6] 5 [Turn over Section B Electronic and Microelectronic Control Systems Answer both questions in this section. 2 (a) A road junction is shown in Fig. 2 where each of the sensors A, B and C outputs logic 1 when it detects a vehicle. The flow of traffic is controlled by the traffic lights X and Y. The traffic lights each contain 2 outputs that indicate either GO or STOP respectively. The indications of X and Y are always the opposite of each other. The traffic lights respond to the following traffic conditions: X indicates GO when no vehicles are detected, or vehicles are in A or B but no vehicles in C, or vehicles are in both A and B. Y indicates GO when vehicles are only in C, or vehicles are in C and also in A or B. (i) Draw a truth table relating the signals from the sensors A, B and C and a signal F that will make X indicate GO. [4] (ii) Minimise the logic expression for F and draw the logic circuit required to control lights X and YX and Y . [6] X X A A B B X X Y Y C C Fig. 2 (b) The logicX circuit used to control X and Y in 2(a)(ii) is to be replaced by a Y STOP programmable system such as a PIC. (i) Draw a programme flow chart to achieve the traffic conditions for X and Y as indicated above. [6] (ii) Briefly outline three advantages of using a programmable system as compared to a logic system such as that designed in 2(a)(ii). [3] A2V3W8 3220 6 [Turn over 3 A circuit used to detect sound and provide a signal is shown in Fig. 3. (a) (i) Briefly describe the mode of operation of one type of microphone. [3] (ii) Amplification is required since the microphone output is only a few millivolts. Suggest suitable values for resistors R1 and RF in Fig. 3 to achieve a gain of 200 given that voltage gain Vo/Vi = 1 + RF/R1. [2] (iii) Calculate the value of input voltage Vi when the maximum possible output voltage Vo occurs. [2] + 5V 5V Vi Vo 1 M R1 Microphone RF 0V Fig. 3 (iv) Explain why a voltage supply of 5 V is required. [3] (b) (i) Briefly explain how you would use a signal generator and an oscilloscope to verify the gain of the circuit shown in Fig. 3. [4] (ii) A microcontroller which has only digital inputs, is to be used as part of a system to monitor the sound level in a room over a period of time. Draw a block diagram showing how the circuit shown in Fig. 3 can be interfaced to the microcontroller and briefly explain the need for any additional devices. [5] A2V3W8 3220 7 [Turn over Section C Pneumatic and Mechanical Systems Answer both questions in this section. 4 Fig. 4 shows part of the drive system to be used in a prototype kart. GGearbox Housing earbox Housing SShaft X haft X Shaft Y Shaft Y OutputShaft Output Shaft M otor Motor Fig. 4 (a) (i) The kart uses a disc based braking system. State one main advantage and one main disadvantage associated with using disc brakes in comparison with drum brakes. [2] (ii) The two rear wheels of the kart have disc brakes which engage at the same time when the foot pedal is operated. Using an annotated sketch, name and draw a suitable brake activation system. [3] (b) (i) The gearbox housing as shown in Fig. 4 consists of two halves. State a suitable seal to prevent oil leakage. [1] (ii) Using an annotated sketch, draw a suitable bearing housing including seal to prevent oil leakage at the output shaft shown in Fig. 4. [3] (c) The drive system as shown in Fig. 4 will use a clutch to transmit motion from shaft X to shaft Y when the motor reaches a particular speed. Using an annotated sketch, name and draw a suitable clutch system. [4] A2V3W8 3220 8 [Turn over (d) Calculate the power supplied by the motor to shaft X to rotate it at an angular speed of 240 rev/min with a torque of 200Nm. [3] (e) The input torque supplied to the gearbox is 350Nm. The two driver gears selected in the gearbox have 30 and 50 teeth and the two driven gears have 45 and 75 teeth. Calculate the output torque. [3] A2V3W8 3220 9 [Turn over 5 Fig 5 shows parts of a pneumatic based prototype Target Game for use in fairgrounds and amusement arcades. Fig 4(a) Fig 5(a) SStart tart A A B B D D C C Fig. 5 (a) The Target Game shown in Fig. 5 is too heavy to be lifted manually and is to be moved using a pulley lifting system which runs on plain bearings. (i) Briefly describe the mechanics of lubrication. [1] (ii) Using an annotated sketch, show a typical plain bearing arrangement. [2] (iii) Sketch a pulley lifting system with a mechanical advantage of 5. [2] (iv) A pulley mounted on a horizontal shaft 50mm in diameter runs on plain bearings for which the friction force is 60N. Showing all calculations, state the work done against friction when the pulley reaches 500 revolutions. [3] A2V3W8 3220 10 [Turn over (b) The Target Game as shown in Fig. 5 is intended to perform the following sequence once the Start valve is switched: Cylinder A outstrokes slowly. Cylinder C outstrokes. Cylinder D outstrokes. Cylinder B outstrokes. Cylinder A instrokes. Cylinder D instrokes. Cylinder B instrokes. Cylinder C instrokes. Cylinder D outstrokes. Cylinder D instrokes slowly. (i) State the pneumatic sequence. [1] (ii) On the pro forma provided (Pro forma answer No. 5(b)(ii)), draw a suitable interlocking/cascade sequential circuit to achieve the desired sequence. [9] (c) The Target Game as shown in Fig. 5 is to be modified to be electro-pneumatically controlled. Briefly explain one main advantage associated with the use of solenoids/ electro-pneumatics to control circuits. A2V3W8 3220 11 [1] [Turn over S 12/06 302-011-1 4 2 8 1 5 6 10 LANE 12 3 9 Foot fault line Lamps 7 Chute Conveyor belt roller Elevator Gearbox Conveyor belt A Plan view of conveyor belts and pin holders Rubber flooring Pin Pit Chute Conveyor belts Motorised gearbox for conveyor belts Elevator Display Board LANE 12 Elevator Conveyor belt B Individual pin holders Sweeper Arm Pin distributor For candidates studying Electronic and Microelectronic control systems Fig. 1(a) 10 9 8 7 6 5 4 3 A2V31 2 3220.02 1 A2V3W8 [Turn over Front plate Sweeper Arm Foot fault line 12 Bowling lane Output Shaft Elevator Gearbox L A NE Elevator Elevator Motorised gearbox for conveyor belts Chute Conveyor belt roller Sweeper Pin distributor Conveyor belt A Plan view of conveyor belts and pin holders Rubber flooring Pin Pit Chute Conveyor belt B Arm Individual pin holders For candidates studying Pneumatic and Mechanical control systems Fig. 1(b) 10 9 8 7 6 5 4 3 2 3220.02 1 A2V3W8 [Turn ove[Turn over 90 degree angular movement first Front plate Sweeper Arm linear movement Sweeper Movement A2V3W8 3220.04 Question No. 5(b)(ii) 12 5 3 START 1 14 A 12 5 3 A2V31IN5 Pro forma answer page (answer number 5(b)(ii)) 1 14 B 12 ADVANCED LEVEL TECHNOLOGY AND DESIGN Assessment Unit A2 3 Unit 6 January 2008 12 5 5 1 1 3 3 14 D 14 C Candidate Number 71 Centre Number A2V3W8 3220.04 Question No. 1(a)(v) or 1(b)(v) A2V31IN2 Pro forma answer page (answer number 1(a)(v) or 1(b)(v)) ADVANCED LEVEL TECHNOLOGY AND DESIGN Assessment Unit A2 3 Unit 6 January 2008 Candidate Number Candidate Number 71 71 Centre Number Centre Number

Formatting page ...

Additional Info : Gce Technology and Design January 2008 Assessment Unit A2 3, Unit 6: Systems and Control in Product Design
Tags : General Certificate of Education, A Level and AS Level, uk, council for the curriculum examinations and assessment, gce exam papers, gce a level and as level exam papers , gce past questions and answer, gce past question papers, ccea gce past papers, gce ccea past papers

gce chat

Horizontal lines at:
Guest Horizontal lines at:
AutoRM Data:
Box geometries: