Proposed drinks machine control system Your company has been commissioned to design a drinks vending machine which will be able to produce a range of hot beverages, for example: Hot chocolate, standard coffee, flat white, tea and soup. For tea and coffee the user can pick with milk and/or sugar. All of these drinks are made by heating up water, then mixing it up in a mixing vessel, the mixture is then dispensed into a disposable cup, the user also has an option to use their own cup. After each drink is dispensed the mixing vessel is cleaned out by running hot water through it for a short amount of time. To do all this, the machine needs to be able to: Accept and validate coins and calculate the current value of the coins inserted Accept instructions to choose a particular drink recipe Heat up the water to the correct temperature then mix the drinks Dispenses and fill the disposable cups for the drinks Return change if the customer has entered an amount greater than price of drink. For example, customer has ordered coffee, cost of drink is 1.60, and the customer has inserted 2 x 1 pound coins, the machine should return the 40p, when the return change (cancel) button is pressed. If the customer wishes to cancel the transaction, all the current balance should be returned to the customer if possible. The machine has a keypad on the front with a keypad as shown in Figure 1, this is used to make the drink selection and to control the engineer's tests. The machine also has an alphanumeric LED display. COD 510 CHARACTERS 2X16 MIDAS LOS 00- Figure 1 Keypad and alpha display The drinks machine is fitted with a GPRS/3G/4G/5G modem card which allows it connect to the internet and be controlled by a service operator. The service operator can find out the current stock and cash levels in the machine as well as be informed via an alert if the machine's stock levels are low or the cash box is full. The operator can also make requests to download accounts information from the machine for a particular accounting period, for example 4/4/2021 to 4/5/2021. Operator access to the machine is protected using a user name and password stored within the machine. There is also a master password available which can be used create new accounts in case the machines memory has been wiped due to hardware failure. Also the recipes for the drinks can be downloaded to the machine online. When the machine requires service (such as needing more coffee or the cash to be collected or has run out of cups), a service engineer visits the machine. The back of the machine is opened, this puts the machine into service mode, the engineer will then collect the cash and does a series of tests by using the keypad. Each engineer has a unique passcode which they need to type into the key pad after opening the service door. If they don't do this within a short time interval the machine goes into alarm mode and sends an alert to the service operator. When the cash is collected, the engineering must record the amount they collect into the keypad, this data is stored in the machine and can be retrieved by the service operator. a Given that the engineer and customer both have to use keypad, for your solution please devise a coding for at least the drink codes. For this part of the solution, try to make it so the customers only need to press the minimal number of key presses possible to get their drink and also make it impossible to get the wrong drink if they only get 1 key press incorrect (i.e. 1 key press wrong should give an invalid key press sequence). This type of code could be said to have a hamming distance of 2 key presses. All tasks for this assignment refer to the given scenario Proposed Drink machine system" (overleaf on page 2). Produce a UML use-case model use-case description that are within the scope of the system, but for this coursework ONLY include human actors. There are THREE actors. Keep all text easy to read and all fonts at least 14pt. For the use cases please provide ONLY a maximum of 5 use cases per actor. If you provide more, the marker will only mark the first 5. Please use the following template for your use case descriptions: ID Actors Name Description Pre-conditions Event flow Id if use case, example UC1 List of relevant Actors Short name for use case Description of purpose of use case What must be true to allow use case to happen Line by line detailed events for the use case Any changes to the systems internal state due to use case executing Any use cases which make up this use case Any optional use cases that are part of initial case What might trigger use case Post-condition Includes Extensions Triggers Proposed drinks machine control system Your company has been commissioned to design a drinks vending machine which will be able to produce a range of hot beverages, for example: Hot chocolate, standard coffee, flat white, tea and soup. For tea and coffee the user can pick with milk and/or sugar. All of these drinks are made by heating up water, then mixing it up in a mixing vessel, the mixture is then dispensed into a disposable cup, the user also has an option to use their own cup. After each drink is dispensed the mixing vessel is cleaned out by running hot water through it for a short amount of time. To do all this, the machine needs to be able to: Accept and validate coins and calculate the current value of the coins inserted Accept instructions to choose a particular drink recipe Heat up the water to the correct temperature then mix the drinks Dispenses and fill the disposable cups for the drinks Return change if the customer has entered an amount greater than price of drink. For example, customer has ordered coffee, cost of drink is 1.60, and the customer has inserted 2 x 1 pound coins, the machine should return the 40p, when the return change (cancel) button is pressed. If the customer wishes to cancel the transaction, all the current balance should be returned to the customer if possible. The machine has a keypad on the front with a keypad as shown in Figure 1, this is used to make the drink selection and to control the engineer's tests. The machine also has an alphanumeric LED display. COD 510 CHARACTERS 2X16 MIDAS LOS 00- Figure 1 Keypad and alpha display The drinks machine is fitted with a GPRS/3G/4G/5G modem card which allows it connect to the internet and be controlled by a service operator. The service operator can find out the current stock and cash levels in the machine as well as be informed via an alert if the machine's stock levels are low or the cash box is full. The operator can also make requests to download accounts information from the machine for a particular accounting period, for example 4/4/2021 to 4/5/2021. Operator access to the machine is protected using a user name and password stored within the machine. There is also a master password available which can be used create new accounts in case the machines memory has been wiped due to hardware failure. Also the recipes for the drinks can be downloaded to the machine online. When the machine requires service (such as needing more coffee or the cash to be collected or has run out of cups), a service engineer visits the machine. The back of the machine is opened, this puts the machine into service mode, the engineer will then collect the cash and does a series of tests by using the keypad. Each engineer has a unique passcode which they need to type into the key pad after opening the service door. If they don't do this within a short time interval the machine goes into alarm mode and sends an alert to the service operator. When the cash is collected, the engineering must record the amount they collect into the keypad, this data is stored in the machine and can be retrieved by the service operator. a Given that the engineer and customer both have to use keypad, for your solution please devise a coding for at least the drink codes. For this part of the solution, try to make it so the customers only need to press the minimal number of key presses possible to get their drink and also make it impossible to get the wrong drink if they only get 1 key press incorrect (i.e. 1 key press wrong should give an invalid key press sequence). This type of code could be said to have a hamming distance of 2 key presses. All tasks for this assignment refer to the given scenario Proposed Drink machine system" (overleaf on page 2). Produce a UML use-case model use-case description that are within the scope of the system, but for this coursework ONLY include human actors. There are THREE actors. Keep all text easy to read and all fonts at least 14pt. For the use cases please provide ONLY a maximum of 5 use cases per actor. If you provide more, the marker will only mark the first 5. Please use the following template for your use case descriptions: ID Actors Name Description Pre-conditions Event flow Id if use case, example UC1 List of relevant Actors Short name for use case Description of purpose of use case What must be true to allow use case to happen Line by line detailed events for the use case Any changes to the systems internal state due to use case executing Any use cases which make up this use case Any optional use cases that are part of initial case What might trigger use case Post-condition Includes Extensions Triggers
