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Refreshment Replenishing Robot (3R)






The main objective of this project was to design and create a robot capable of delivering a beverage to a specific location, when needed. To achieve this goal, two teams were combined and worked together into building an acquiring and delivering robot as well as a dispensing and replenishing station.



Part 1

Acquiring and Delivering

François-Xavier Bonneville, Pierre-Alexandre Poirier, Martin Villeneuve, Mechanical Engineering, University of Ottawa




Our main objective was to build a robot that would automatically deliver beverages to the user, with minimal intervention from the latter.  In order to do so, we opted for a vehicle design.  In order for the robot to accurately venture from the base station (built by team B10) to the user (at a couch, for example), we decided to make a line following robot; therefore, the user could set a line of electrical tape as they wished to control the robot’s path.  We also wanted to eliminate the need for programming in an attempt to make the project purely electronic, where the actuators are directly driven by signals picked up by the sensors.  We also wanted to solder our circuit into a single, compact circuit to increase reliability.



Related Work


We performed extensive research early in the design stage to find was to eliminate the use of a microcontroller (like an ATMEGA chip, for example) in our circuit, thus avoiding unnecessary programming.  We came across the following website and used the displayed circuit as a basic starting point for ours:

However, significant changes were made as shown on our circuit diagram.


Circuit Design and Component List


Please refer to the power point presentation for the circuit diagram of our project, as well as a list of components used during our project.  Before building our project, we used Multisim to simulate a few sections of our circuit: the sensors and the digital part (logic gates with 4066).  Both worked and behaved as expected, giving us the go-ahead to start building.




Project testing was quite simple.  After having success using Multisim, we constructed our circuit on multiple breadboards until we reached satisfactory behavior.  All changes made during this phase were updated on revision 1.1 of our circuit.  Next we transferred our circuit little by little to a copper circuit board and soldered it all together, always testing for proper functionality as we worked.  This eased troubleshooting since problems would always be caused by something we changed since the last successful test.  Final testing took place calibrating the potentiometers and integrating our project with team B10s.



Part 2

Dispensing and Replenishing

Jonathan Armstrong, Justine Dagenais and Antoine Schryer, Mechanical Engineering, University of Ottawa




To load the robot with a beverage, we needed to build an automated dispensing station. That station had be able to sense the need for a new beverage before dispensing it.  Our goal was to build a weight-sensing coaster that would be designed to trigger that station when the beverage was empty.



Circuit design and component list

The coaster consists of a force-varying resistor that determines when the beverage is empty.  It is connected to two comparators to make sure that no beverage is dispensed if there is no bottle on the coaster.   Once the beverage is empty, the current goes through a delay circuit preventing any signal to be sent by simple weight fluctuations caused by the consumer.  The weight-sensor is connected to a radio device that gets activated when the criteria listed above are met.  This device generates a radio frequency that will be received by the dispensing station.



Once the radio device, mounted on the dispensing station, receives the signal from the coaster, it triggers the motor allowing a beverage to be loaded onto the    robot.  The dispensing mechanism consists of a motor with a gearbox connected to a lever. This lever is attached to a “camshaft” which allows only one beverage to be dispensed when the motor is turned on. Once the robot reaches its destination and a new beverage is put on the coaster, the motor will turn off letting the “camshaft” return in its original position with the help of a spring. The next beverage is then ready to be dispensed.




For additional information on the components and to view the circuit design, please refer to the power point presentation.







As a whole, we are very proud of our project, since we were able to build something functional and useful from only very basic components, without using programming or pre-manufactured PCBs, for example.  We learned many interesting things about electronics this semester and this project was a good way to tie it all together.





 The Video Again