The objective of this lab was to download data from a test run using the automatic control system and then convert EEPROM data readouts to an actual framework. From the data, the incremental energy, total energy, and supplied power to the AEV will be calculated. This understanding of power and energy usage through the AEV is crucial in limiting the amount of energy required for the vehicle to safely move around Jurassic Park.
We used a sample code to test different phases on the AEV. Analyzing theses phases can help us determine the efficiency for a variety of processes. The figure depicted below shows the change in power over time for the AEV during these phases.
Figure 1
Arduino Code for the above Phases:
\\1. Run no power for 1 second.
⌊motorSpeed(4,0); goFor(1);
\\2. Accelerate all motors from 0% to 30% power in 2 seconds.
⌊ celerate(4,0,30,2);
\\3. Run all motors at a constant speed (30% power) for 2 seconds.
⌊ motorSpeed(4,30); goFor(2);
\\4. Reverse all motors.
⌊ reverse(4);
\\5. Run all motors at a constant speed (40% power) for 1 second.
⌊ motorSpeed(4,40); goFor(1);
\\6. Decelerate all motors from 40% power to 20% power in 1 second.
⌊celerate(4,40,20,1);
\\7. Brake all motors for 1 second.
⌊brake(4); goFor(1);
\\8. Reverse motors.
⌊ reverse(4);
\\9. Run all motors at constant speed (20% power) for 1 second.
⌊ motorSpeed(4,20); goFor(1);
\\10. Brake all motors
⌊ brake(4);
Each phase shows the power that was used versus the time that the process was occurring. During phase 1 the Arduino used very little energy and was barely moving. The little energy that was consumed was likely from the Arduino turning on. Phase two was the acceleration phase which shows that the power used at this phase was increasing. Phase 3 was running at a constant speed, therefore the power was increasing at rate according to time. The jump from phase 3 to 4 was highly inefficient. This is likely a result of the fact that the motor did not accelerate, but instantly jumped to a higher power. This shows that in the final AEV design there should only be two motors, because we do not want an even bigger more inefficient power jump. Phase 5 was similar to phase 2, except that it was decelerating so it used less power as the phase went on. Phase 6 the Arduino was already on and was not moving, thus it used no power the entire time. The power jump to phase 7 is inefficient because again the motors were unable to warm up.
We also had many equations to calculate the parameters.
Equations
Time t=tE/1000, where t=time (seconds) and tE=EEPROM time (milliseconds)
Current I=(IE/1024)*VR*(1Amp/.185Volts), where I=current (amps), IE=EEPROM equivalent
current, and VR=Arduino Reference Voltage
Voltage V=15*VE/1024, where V=Voltage and VE=EEPROM equivalent voltage
Power Pin=V*I, where Pin=Power (watts), V=Voltage (volts), and I=Current (amps)
Incremental EI=(P1in+P2in)/2*(t2-t1), where Pin=Power (watts) and t= Time (seconds)
Energy
Total Energy E=n=1NEn, where E= Energy (Joules)