# 2022/12/03 飛試
###### tags: `Flight Test Report`

[toc]

## Introduction
### Test Subjects
- Coyote.v2 rocket
- Explosive parachute ejection mechanism
- 20cm Nipple made solid-state motor
- Nipple made launch rail
- Reaction wheel for spin control
- Video transmittion
- New ground station interface

---

## Staffing
- Flight director: Nick Chung
- Vice director ：林柏漢
- Medical officer：張子凡
- Camera：林柏漢
- Launch rail installation: 子凡、德慶、湲晨

---

## Profile
- 集合時間:12/03 4:00 A.M.
- 集合地點:大學路22巷30號(天主教台南青年中心)
- 飛試地點:小美軍

---

## Items
| 項目 | 數量 | 準備狀況 |
| ----------------- | ---- | -------- |
| 火箭發射架 | 1 | v |
| 遙控點火 | 1 | 德慶帶 |
| 地面站 | 1 | v |
| 地面點火器 | 1 | v |
| 箭載航電板 | 1 | v |
| 備用電池_4號 | 4 | v |
| 電子點火頭(長:1m) | 20 | v |
| 電火布 | 2 | v |
| 滅火器 | 1 | v |
| 黑火藥 | 1 | v |
| 行動銲接組 | 1 | v |
| 安全帽 | 5 | v |

- 其餘物品記載在下方火箭發射標準作業流程

---

## Flow
- [火箭發射標準作業流程](https://hackmd.io/JKn-EL-8SMqw-yXcMZmUAg)
### X-day
- [ ] 1. 提早 15 分鐘在指定場所集合
- [ ] 2. 確認成員集合情況(若有成員遲到，留下兩位幹部(同車)待命)
- [ ] 3. 準時出發
- [ ] 4. 發射架安裝、安裝火箭尾翼
- [ ] 5. 上發射架，準備飛試
- [ ] 6. 發射前大合照
- [ ] 7. 指定各項人員站定位置
- [ ] 8. 安裝點火頭
- [ ] 9. 進行飛行前航電檢查
- [ ] 10. 飛行倒數
- [ ] 11. 落地確認
- [ ] 12. 回收
- [ ] 13. 箭體損毀情況評估
- [ ] 14. 數據存儲及確認
- [ ] 15. 收拾現場並檢查遺留物及垃圾
- [ ] 16. 離開前人員檢查
- [ ] 17. 回到成大人員檢查
- [ ] 18. 訂定當天飛試檢討時間
- [ ] 19. 於社辦做飛試檢討

---

## Limitation
- [飛機航向](https://www.flightradar24.com/22.95,120.14/9)
- [中央氣象局臺南市南區測站觀測資料](https://www.cwb.gov.tw/V8/C/W/OBS_Station.html?ID=C0X11)
- 風速轉換表
- 預估清空範圍

---

## OpenRocket
- CG at 78.6 cm from top
- CP at 93.1 cm from top
- Stability: 1.81 cal
- Total mass: 4562 g

---

## System Detail and Review
### System Engineering
- Review :
- To be improved :

### Launch Pad
- Version : V2.1
- Review :
- Side support position will block the path of two fins, the temporary solution is moving the side support from the front aluminum extrusion to the back one.
- Lugs have a large frictional resistance.
- To be improved :
- New method of the side support install, avoid potential block of any parts the rocket.
- Design new lugs to reduce the frictional resistance.

### Propulsion
- Version : MD20
- Review :
- Max. thrust: 276.2 N
- Avg. thrust: 175.3 N
- Total impulse: 530.8 N•s
- Burnung time: 3.03s
- Propellant mass: 571.8 g
- Isp: 94.6 s
- To be improved :
- nozzle erosion
- [Thrust test report](/fjUh-GNqR82sBBT41ele7g?view#1119)

### Avionics System
- Board Type: ISP8266
- Version: V2
- Test subjects:
- Reaction wheel control
- IMU data acquisition
- Video transmittion
- Test data:
We lost the flight data after the crash. The snapshot was the only data we'd got.
- Review:
- Judging from the footage the height was only about 10 to 20m. However, the data shows that the apogee was at about 75m. Guessing it was because of the tumbling of the rocket causing the huge pressure change.
- The accelerometer shows that the first 1.2 second, the absolute of three axis acceleration is about 2g. However, the altitude is at 0m. It was because of the vibration from reaction wheel.
- The velocity estimation is differentiated from height, however, due to the inaccurate timing, the velocity isn't trustable so far, therefore we can ignore that.
- Data acquasition was saved at onboard flash using filesystem. In order to reduce saving time, we close the file at apogee and stop time.(Frequently open and close file will consume lots of time) However, once the power is off without closing file, the data will be lost. This is why we didn't get any data from this mission.
- To be improved
- Velocity Estimation: Using interrupt to control timing.
- Filtering the data: Add low pass filter and Kalman filter.
- Data acquasition under extreme environment: Using eeprom instead of filesystem.

### Ground Station
- Version:
- Review:
- The GPS location was wrong.
- Because of the false GPS data, the wind data was also wrong.
- Because of the absolute acceleration data, we can not see what happened to the three orthonormal acceleration of each axis.
- It was difficult to identify what color of line represents what axis of angular velocity in Gyro block.
- It has no backup of sensor's data can download when on-board avionics broken.
- To be improved
- GPS: Add GPS module in ground station's PCB to provide more precise location data.
- Sensors Chart: Add more clear and bigger chart when user click the small preview card.
- Backup Data: Store the communication's log in `localStorage` and add a download button.

---

## Footage
[Video link](https://drive.google.com/drive/folders/1F5mTpf_2T9YoSjxcNHA0WI62-C9Qtr2z?usp=share_link)

---

## Overall Review
1. The potential problem causing failure
1. Wind strength
2. Stability
3. Thrust weight ratio
4. Launch rail length
5. Launch lug
6. Reation wheel
2. laun