Enhanced ATV Larvicide Spreader
Team: Sadie Alldredge, Diego Baeza and Miles Drennan
Project
The Cache Mosquito Abatement District (CMAD) controls the mosquito population in Cache Valley to limit cases of West Nile Virus. The main methods used to control the mosquito larvae are granular and oil larvicides that are spread by various methods throughout the valley.
The purpose of this project was to design and build a larvicide spreader that mounts on the back of an ATV. The following criteria were used:
- Easy and accurate calibration
- Easy to maintain
- Lightweight
- Durable in outdoor conditions
- Granular and liquid larvicide capacity
Design Overview
The design consists of liquid and granular larvicide spreaders mounted on an aluminum frame. It includes a tank and sprayer system with a tank connected to a pump, side spray nozzles, and a spray wand. It also includes a hopper and spreader system with an auger that feeds larvicide onto a spinner disk, distributing material from 90–180 degrees using adjustable side guards.
Performance Review
| Requirement/Constraint/Goal | Target | Threshold | Predicted Performance | Actual Performance |
|---|---|---|---|---|
| Max spreader width (in.) | N/A | 42.75 | 37 | 35 |
| Spreader weight (lb) | 50 | 80 | 60 | 40.6 |
| Granular larvicide capacity (lb) | N/A | 30-40 | 54 | 40 |
| Liquid larvicide capacity (gal) | 10 | 8 | 10 | 10 |
| Multi-directional guard (°) | N/A | 90-180 | 90-180 | 90-180 |
| Power Required (W) | N/A | 120 | 16-38 | 16-38 |
| Frame Factor of Safety | 5 | 3 | 7 | N/A |
| Larvicide Application Rate (lb/acre) | N/A | 5-20 | 0-26 | 3.5-24.1 |
The weight of the spreader was reduced to half the threshold value by using lightweight parts and an aluminum frame. The auger screw was tested by measuring the larvicide flow at various power levels to increase precision and accuracy of the calibration measurements as shown in the graph. The guard system was tested by using guard prototypes with different angles and lengths to reduce larvicide waste.
Conclusions
Design Requirements:
The product met all design requirements; however, longterm durability remains unverified due to design complexity.
Lessons Learned:
The main lessons learned were to ask better questions early, do more testing, and evaluate designs before committing to a solution. If repeated, the project would focus on simpler components and prototype testing before building the final product.
Recomendend Future Work:
Develop a simpler speed control system, test the effects of battery degradation on calibration reliability, add a chain guard, and find alternatives to specialty parts.
Special thanks to: Richard Rigby