本倉庫說明
產品詢價與技術問題請聯繫我們: [email protected]
| 資料夾 | 說明 |
|---|---|
| 01_UserManual | IMU 產品用戶手冊 |
| 02_GUI | IMU 快速上手軟體，圖表呈現、數值、記錄、模組設定功能 |
| 03_Examples | 資料接收程式範例 |
| 04_UsbDrivers | 提供 Windows/Linux 的 USB 驅動 |
- HI221/HI221 Dongle 無線慣性感測器(PDF)
- HI226 六軸慣性感測器(PDF)
- HI229 九軸慣性感測器(PDF)
- CH100 六軸工業級貼片式高精度慣性感測器(PDF)
- CH110 六軸IP67外殼，RS232工業級高精度慣性感測器(PDF)
包含IMU系列產品的 :
- X Y Z 多軸即時數據、波形圖
- 3D 姿態顯示
- CSV 數據紀錄
- 加速度與陀螺儀FFT分析、低通濾波功能，協助分析振動
- 模組參數設定，如採樣率、鮑率、ID、無線節點 GWID
如有發現問題請聯絡 [email protected]
- 如遇上執行 GUI 提示缺少 msvcpXXX.dll 的狀況，請安裝 VC_redist.x86.exe
- 如 Windows 系統未成功識別 IMU 裝置，請安裝 USB驅動包
基本接收資料的範例包含以下程式語言與環境(恕不提供免費額外的程式修改服務):
- C#
- Python
- QT C++
- ROS
- STM32
- Ubuntu
Example Code 下載: 連結
6軸9軸的概念很好理解：說白了就是模組上裝了哪些，多少感測器
6軸 : 三軸(XYZ)加速度計 + 三軸(XYZ)陀螺儀(也叫角速度感測器) 9軸 : 6軸 + 三軸(XYZ)磁場感測器6軸模組可以構成VRU(垂直參考單元)和IMU(慣性測量單元)，9軸模組可以構成AHRS(航姿參考系統) IMU: 慣性測量單元，可以輸出加速度和角速度。並不輸出姿態角等其他資訊 VRU: IMU的基礎上內置姿態解算演算法，可以輸出姿態資訊。
靜止狀態下加速度計可以測得重力向量並作為參考，所以靜態下俯仰橫滾角不會漂移而且精度比較高，然而由於航向角與重力垂直，沒有絕對參考，水平方向上的航向角誤差會隨著時間慢慢變大，變的越來越不準 。
當模組運動時，加速度計測量的不僅僅只有重力，還有其他運動加速度(有害加速度)，所以模組運動中是不能用重力向量作為參考修正俯仰橫滾角的。一個簡單的結論就是：如果模組長時間處於大機動狀態，那麼三個歐拉角誤差都會隨時間變大(越來越不準)，一旦靜止，俯仰橫滾角會被重新"拉"回到正確的位置，而航向角因為沒有參考則不會得到校正。
AHRS: VRU的基礎上修改演算法，可以解算被測物體的全姿態，包括絕對的航向角(與地磁北極的夾角)，因為要用到地磁感測器，所以必須是9軸模組。另外室內由於地磁場畸變非常嚴重，AHRS 在室內也很難獲得準確的絕對航向角。 GPS: 美國的全球衛星定位系統：Global Position System 翻譯過來就叫全球衛星定位系統。 GNSS: 全球衛星定位系統，GPS，北斗，GLONASS 等系統的總稱，每一個系統叫做一個"星座"GNSS/INS: 衛星/慣導組合導航系統
IMU:
慣性測量單元，可以輸出加速度和角速度。並不輸出姿態角等其他資訊
VRU:
IMU的基礎上內置姿態解算算法，可以輸出姿態資訊。
靜止狀態下加速度計可以測得重力向量並作為參考，所以靜態下俯仰橫滾角不會漂移而且精度比較高，然而由於航向角與重力垂直，沒有絕對參考，水平方向上的航向角誤差會隨著時間慢慢變大，變的越來越不准 。
當模組運動時，加速度計測量的不僅僅只有重力，還有其他運動加速度(有害加速度)，所以模組運動中是不能用重力向量作為參考修正俯仰橫滾角的。一個簡單的結論就是：如果模組長時間處於大機動狀態，那麼三個歐拉角誤差都會隨時間變大(越來越不準)，一旦靜止，俯仰橫滾角會被重新"拉"回到正確的位置，而航向角因為沒有參考則不會得到校正。
AHRS:
VRU的基礎上修改算法，可以解算被測物體的全姿態，包括絕對的航向角(與地磁北極的夾角)，因為要用到地磁感測器，所以必須是9軸模組。另外室內由於地磁場畸變非常嚴重，AHRS 在室內也很難獲得準確的絕對航向角。
理論可以，實際不行(沒有意義)。如果沒有其他方式糾正偏差(比如GPS)，那麼位置會很快發散，比如HI226模組，加速度積分得速度，速度積分得位置。這樣二次積分下來，就算是靜止條件下，1分鐘也會飄移幾十米。高速運動/隨機飄出1KM也是有可能的。 真正純慣性導航解算得到穩定的位姿應用的都是高端IMU(光纖，雷射陀螺儀等)一般都價值不菲。
6軸一點都不會，9軸肯定會，而且非常大。所以9軸模式一般不適用於機器人等周圍有磁性物質的場合。
6軸模組航向角飄移是必然的，只是程度的高低不同而已，演算法無法解決晶片性能的極限。需要注意的是所有姿態模組都需要上電靜止1s左右以獲得陀螺零偏，否則航向角飄移會更嚴重，詳見產品手冊描述。
9軸模組需要配置為9軸模式，並且地磁經過校準，並且無地磁空間畸變干擾的環境下才能輸出穩定無飄移的航向角，室內環境下：辦公桌周圍，廠房，實驗室，儀器設備旁的區域空間磁場畸變非常嚴重，9軸模式下航向角指北精度一般都比較差，初次使用可以到戶外先測試模組性能，在拿回室內比較。
一個簡單的定性分析方法：
將模組水平放置，穩定後拿起模組進行隨機機動運動(慢慢動 不要太劇烈，不要超出陀螺量程)，運動一定時間(1min)後回到水平位置，這時候會發現俯仰橫滾角有一個緩慢的 "回正" 過程。
這是由於運動中加速度計測量的不再只有重力向量，所以無法提供俯仰橫滾角的絕對參考，只能靠陀螺積分來遞推姿態，隨著時間流逝，純陀螺積分姿態必然會有誤差。
重新水平放置後，模組處於靜止狀態，加速度計測量的又只有重力向量，所以又可以繼續為俯仰、橫滾角提供絕對參考，所以才有 "回正" 過程。 所以，從"回正"的大小程度(而不是快慢)上就可以簡單比較這塊產品的陀螺儀性能。
無線接收機接收所設定的 GWID 頻段內在線的所有節點，並根據節點自己的 ID 來區分節點。
若使用者已經依照說明書設定不同無線頻段 (GWID)，每組接收機距離超過 5 米以上，干擾機會小。幾項建議:
- 5 米範圍內不建議使用超過 2 組無線接收機
- 建議每組接收機與配對節點之間距離相近，例如
GWID=1的接收機與節點距離最近，避免跟GWID=2的節點距離最近。
取決於所設定之波特率。當接收機波特率設定為最大 921600，可連接 8 顆 100Hz 之 HI221，16 顆 50Hz 之 HI221。
非常敏感，理論上來講陀螺對加速度應該是不敏感的(一個測量角速度，一個測量加速度)，但實際上MEMS器件並非如此(完美)。陀螺對加速度(振動)也是敏感的，並且叫做，"重力敏感度或G敏感性"。這些指標實際上比零偏穩定性還要重要的多，對於振動場合，低成本IMU的表現相較於光纖陀螺和高端MEMS要差的多(其他指標相同的情況下），實際上光纖陀螺因為測量原理不同，壓根沒有這個振動敏感性指標)。例如：IMU周圍有振動源(風扇)，這會極大的影響IMU的輸出數據的精度。
模組波特率只可能為：9600, 115200, 256000,460800,921600, 1000000. 輸入任何其他的波特率都無效，如果忘記了之前的波特率，一個一個試下即可。
Introduction
For product inquiries and technical questions, please contact us: [email protected]
| Folder | Description |
|---|---|
| 01_UserManual | IMU Product User Manual |
| 02_GUI | IMU quick start software, chart, raw data, recording, module setting |
| 03_Examples | Example of data receiving program |
| 04_UsbDrivers | Provides USB drivers for Windows/Linux |
- HI221/HI221 Wireless IMU (PDF)
- HI226 6-axis IMU (PDF)
- HI229 9-axis IMU (PDF)
- CH100 9-axis Industrial SMD High Precision IMU (PDF)
- CH110 9-axis IP67 housing, RS232 industrial and high-precision IMU (PDF)
Including IMU series products:
- X Y Z multi-axis real-time data, waveform graph
- 3D attitude display
- CSV data record
- Acceleration and gyroscope FFT analysis, low-pass filtering function to help analyze vibration
- Module parameter settings, such as sampling rate, baud rate, ID, wireless node GWID
If you find any problems, please contact [email protected]
- If the GUI prompts that msvcpXXX.dll is missing, please install VC_redist.x86.exe
- If the Windows system fails to recognize the IMU device, please install the USB driver package
Examples of basic received data include the following programming languages and environments (no free additional programming modification services are provided):
- C#
- Python
- QT C++
- ROS
- STM32
- Ubuntu
Example Code download: link
The concept of 6 axes and 9 axes is easy to understand: to put it bluntly, it is what and how many sensors are installed on the module
6-axis: three-axis (XYZ) accelerometer + three-axis (XYZ) gyroscope (also called angular velocity sensor) 9-axis: 6-axis + three-axis (XYZ) magnetic field sensor The 6-axis module can form a VRU (Vertical Reference Unit) and IMU (Inertial Measurement Unit), and the 9-axis module can form an AHRS (Attitude Reference System) IMU: Inertial Measurement Unit, which can output acceleration and angular velocity. Does not output other information such as attitude angle VRU: Built-in attitude calculation algorithm based on IMU, which can output attitude information.
In the static state, the accelerometer can measure the gravity vector and use it as a reference, so the pitch and roll angle will not drift and the accuracy is relatively high in static state. However, since the heading angle is perpendicular to gravity, there is no absolute reference, and the heading angle error in the horizontal direction will be As time gets bigger and bigger, it becomes more and more inaccurate.
When the module is in motion, the accelerometer measures not only gravity, but also other motion accelerations (harmful accelerations), so the gravity vector cannot be used as a reference to correct the pitch and roll angles during module motion. A simple conclusion is: if the module is in a large maneuvering state for a long time, the three Euler angle errors will become larger (more and more inaccurate) with time. Once stationary, the pitch and roll angles will be "pulled" back again. to the correct position, and the heading angle will not be corrected because there is no reference.
AHRS: The algorithm is modified on the basis of VRU, which can calculate the full attitude of the measured object, including the absolute heading angle (the angle with the magnetic north pole). Because the geomagnetic sensor is used, it must be a 9-axis module . In addition, due to the severe distortion of the geomagnetic field indoors, it is difficult for the AHRS to obtain an accurate absolute heading angle indoors. GPS: American Global Positioning Satellite System: Global Position System The translation is called Global Positioning Satellite System. GNSS: Global Positioning System, GPS, Beidou, GLONASS and other systems, each system is called a "constellation" GNSS/INS: Satellite/Inertial Navigation Integrated Navigation System
IMU:
Inertial measurement unit, which can output acceleration and angular velocity. Does not output other information such as attitude angle
VRU:
Built-in attitude calculation algorithm based on IMU, which can output attitude information.
In the static state, the accelerometer can measure the gravity vector and use it as a reference, so the pitch and roll angle will not drift and the accuracy is relatively high in static state. However, since the heading angle is perpendicular to gravity, there is no absolute reference, and the heading angle error in the horizontal direction will be As time gets bigger and bigger, it becomes more and more inaccurate.
When the module is in motion, the accelerometer measures not only gravity, but also other motion accelerations (harmful accelerations), so the gravity vector cannot be used as a reference to correct the pitch and roll angles during module motion. A simple conclusion is: if the module is in a large maneuvering state for a long time, the three Euler angle errors will become larger (more and more inaccurate) with time. Once stationary, the pitch and roll angles will be "pulled" back again. to the correct position, and the heading angle will not be corrected because there is no reference.
AHRS:
Modify the algorithm on the basis of VRU, which can solve the full attitude of the measured object, including the absolute heading angle (the angle with the geomagnetic north pole). Because the geomagnetic sensor is used, it must be a 9-axis module. In addition, due to the severe distortion of the geomagnetic field indoors, it is difficult for the AHRS to obtain an accurate absolute heading angle indoors.
Theoretically yes, but not in practice (doesn't make sense). If there is no other way to correct the deviation (such as GPS), then the position will diverge very quickly, such as the HI226 module, the acceleration is integrated into the velocity, and the velocity is integrated into the position. In this way, after the second integration, even under static conditions, it will drift tens of meters in 1 minute. It is also possible to move at high speed/randomly drift out 1KM. High-end IMUs (optical fibers, laser gyroscopes, etc.) are used to obtain stable poses from pure inertial navigation solutions, which are generally expensive.
6 axes will not at all, 9 axes will definitely be, and very large. Therefore, the 9-axis mode is generally not suitable for situations where there are magnetic substances around such as robots.
The heading angle drift of the 6-axis module is absolutely necessary, but the degree is different, and the algorithm cannot solve the limit of chip performance. It should be noted that all attitude modules need to be powered on for about 1s to obtain the zero offset of the gyro, otherwise the heading angle drift will be more serious, see the description in the product manual for details.
The 9-axis module needs to be configured in 9-axis mode, and the geomagnetism has been calibrated, and a stable and drift-free heading angle can be output in an environment without geomagnetic space distortion interference. In indoor environments: around desks, workshops, laboratories, instruments and equipment The spatial magnetic field distortion in the adjacent area is very serious. In the 9-axis mode, the accuracy of the heading angle pointing to the north is generally poor. For the first time, you can test the performance of the module outdoors and compare it indoors.
5. Without professional equipment such as a turntable, how can you easily and quickly evaluate the dynamic accuracy qualitatively?
A simple qualitative analysis method:
Place the module horizontally, pick up the module and perform random maneuvering motion (slowly move not too violently, do not exceed the gyro range), and return to the horizontal position after moving for a certain period of time (1min), at this time, you will find pitch and roll The corners have a slow "back-to-right" process.
This is because the accelerometer in motion is no longer only the gravity vector, so the absolute reference of the pitch and roll angle cannot be provided, and the attitude can only be recursively derived by the gyro integral. With the passage of time, the pure gyro integral attitude will inevitably have errors .
After re-positioning, the module is in a static state, and the accelerometer only measures the gravity vector, so it can continue to provide absolute reference for the pitch and roll angles, so there is a "back to positive" process. Therefore, the gyroscope performance of this product can be simply compared from the degree of "return to positive" (rather than speed).
The wireless receiver receives all the nodes online within the set GWID frequency band, and distinguishes the nodes according to their own IDs.
If the user has set different wireless frequency bands (GWID) according to the manual, the distance between each group of receivers is more than 5 meters, and the chance of interference is small. A few suggestions:
It is not recommended to use more than 2 sets of wireless receivers within 1.5 meters 2. It is recommended that the distance between each group of receivers and the paired node is close. For example, the receiver with
GWID=1is the closest to the node, and avoids the closest distance to the node withGWID=2.
Depends on the set baud rate. When the receiver baud rate is set to the maximum 921600, it can connect 8 HI221 with 100Hz and 16 HI221 with 50Hz.
Very sensitive, theoretically gyroscopes should be insensitive to acceleration (one to measure angular velocity, one to measure acceleration), but in practice MEMS devices are not (perfect). Gyros are also sensitive to acceleration (vibration) and are called, "gravity-sensitive or G-sensitive". These indicators are actually more important than the zero-bias stability. For vibration applications, the performance of low-cost IMUs is much worse than that of fiber-optic gyroscopes and high-end MEMS (other indicators are the same). In fact, fiber-optic gyroscopes are due to The measurement principle is different, there is no such vibration sensitivity index at all). For example, there is a vibration source (fan) around the IMU, which will greatly affect the accuracy of the output data of the IMU.
The module baud rate is only possible: 9600, 115200, 256000, 460800, 921600, 1000000. Entering any other baud rate is invalid. If you forget the previous baud rate, you can try one by one.