Line Tracking Robot Racer- The final model

We reviewed the second model together ready to plan for our final Racer!

The first thing we noticed was that using Plywood for the body was not as successful as we had hoped, this material is prone to warping, and when this happens it will cut inaccurately in the laser cutter and disfigure the final shape, so we decided to return to MDF.

Secondly, we needed to fully arrange the wires this time so that they are neatly organised making it more aesthetically pleasing and understandable. We wish to achieve this by cutting slots into the top MDF layer, for the wires to be pulled through. We also chose to solder down some wires for more reliable contact.

We also cut a section out of the top MDF layer for the Switch to slot into, this made huge improvement to the aesthetic and ease of use for the switch.

And finally we designed a place for the Egg to sit, we decided to take the name from the elastic band racer ‘Dream Ender’ and create ‘Dream Ender II’. We went with the theme of this name creating a Devil seat for the egg, and engraved the seat and wheels with this name.

We purchased a few Arduino Nanos, since they would take up less space and be lighter in comparison to a regular sized Arduino, but for some reason they drained all power for the motors, we are unsure if this was due to them being so cheap, or if the soldering caused them damage. Because of this we had to return back to the orginal Arduino therefore were unable to shed a potentially significant amount of weight. This time it weighed around 325 grams, we expected this due to the extra weight of the egg support and the use of MDF.

20170330_165739

Speed:

We returned back to the 2 meter track for the final time, sett the PWM (pulse width modulation) pins to 255 to calculate the speed.

Speed = Distance / Time

Speed = 2 / 6.31

Speed = 0.31 meters per second

Surprisingly, the speed was reduced slightly by 0.02 meters per second. We believe this could be due to one of the wheels not being completely straight, to help fix this we added pieces of plywood for support and stability.

Acceleration=

Acceleration = 0.049 meter / square second {m/s2}

80mm Wheels Acceleration = 0.055 meter / square second {m/s2}

A decrease in 0.006 meter / square second {m/s2}

Force 

Looking at the force required to move the object.

Force = Mass X Acceleration

Force = 0.325 x 0.049

Force = 0.015925 N

Due to the lighter weight, it took 0.003325 N less force to move the Racer and the cost of a slightly reduced speed, therefore there was no real increase in efficiency.

We tested the Racer on our track after testing it on the 2 meters. It finished it flawlessly, so we chose to create a more complex track with sharp corners, as we were unsure on what we would be facing on the day. Unfortunately, the racer did not always make these sharp corners , so we reduced the speed and delays to be safe. We also coded the racer so that it was stop completely when both sensors faced the black tape (therefore will stop at the finish line).

If we were to do this again we would used more sensors, designed and made much more stable wheels, and a more pleasing aesthetic.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s