In Project Collisions, I am creating a system to deliver first aid kits by drones. The drone will release the package from a height up to 10 meters and my job as an engineer is to develop a solution so that the package is protected in its fall.
For Drop 0, a package with the dimensions of 22 by 26 by 7 was dropped from a height of 5 meters. Below is a photograph of the package:
The package will hold:
a first aid kit with alcohol pads, band-aids, bandages, cotton pads, medical tape gloves, a mask, tweezers, a mini blanket , and most importantly instructions, items are organised like this:
<insert image of your drawing of the inside of your package>
The purpose of Drop 0 is to get baseline data about our package. The group developed a testing procedure so that we can be consistent on how data is collected throughout the design cycle.
Since I wasn’t there during the drops, my teammates noticed that most of the time the delivery package hit the force plate, it would always hit the sides or the corners of it. The following Data was collected:
The average time it took for our package to fall the 5 meters was about 1 sec. Using LoggerPro, we plotted out the fall of the package.
After the Package fell, it kind of hit one corner of the force plate and bounced off.
A force plate at the bottom of the drop was used to collect data on the impact force of the package. Our group was kind of successful in terms of accuracy, because out package landed on top of the force plate only leaning a little to one side, but if did not fall of onto the table. As a project metric for accuracy, we want our project to land as close to the target as possible, because in some cases the person in need might not be able to get near the med kit if it is at a far distance or got stuck in a tree.
The average force on impact was about 120 N.
As a project metric, our group has decided to build a parachute big enough to reduce the force by 25%.
Summary: Project Metrics
Our team has decided that the three most important criteria to design towards accuracy, velocity and force. Below, each metric is described, and the goals were determined by data from Drop 0.
- Accuracy: The distance in cm from our target + within 10 cm of the force plate
- Velocity The speed of the fall + 50% velocity reduction
- Force: How hard it hits the ground + we want to try reduce the speed by 25%
Our group is now building the first prototype. I hope that using a parachute won’t reduce accuracy and just float away.