sophia lee
Member
Install TF SERIES module on your drone vertically to the ground so you can get the absolute altitude of your drone. Here is how to install our module on PixHawk. We provided two methods below.
1. How does TF SERIES work on PixHawk
Lidar’s are used in flight modes which have height control, such as....
PixHawk interface for rangefinder are I2C , Analog， Serial. Details are on http://ardupilot.org/copter/docs/common-rangefinder-landingpage.html
2. Serial Mode
We recommend using Serial to send altitude signal to PixHawk.
Cautions: If you use serial, please update your firmware, make sure is newer than V 3.3.3.
2.1 Wire
Pic. 1(a) Connect TF SERIES to PixHawk via Serial
Pic. 1(b) Connect TF SERIES to PixHawk via Serial
2.2 Mission Planner
Connect Flight Controller to MP, click CONFIG/TUNING then select Full Parameter List change parameters as below:
See in Pic.2 and Pic.3
Pic.2 Serial parameter configuration
Pic.3 Serial parameter configuration
If Bad Lidar Health error occurs, please check if TF SERIES LiDAR window first, see whether TF SERIES emit red LED light. If there`s no red LED light, please check power supply. (Sometimes PixHawk have Serial 4/5 power supply issue) If there is LED light, please check if you wire the Serial correctly. If you still get this error message and got no reading in sonarrange/sonarvoltage, please connect TF01 to TELEM2 (like Pic.1(b))and change the Parameter for Serial 2 as below.
TF SERIES data is first send to a STM32 board and data is translated into AD data then sent to PixHawk.
Caution: TF SERIES, STM32 board and PixHawk shall share a common-ground.
Pic. 4 connect TF SERIES to PixHawk
3.1 Wire
Connect TF SERIES to input distance data using analog into PixHawk
Pic. 5 Analog input wire,
Red: 3.3V
Orange: AD analog signal
Black: GND
1
2
3
3.1
3.2 Mission Planner Configuration
Connect Flight controller to MP, select Full Parameter List in Config/Tuning, find and change the parameters below:
When all parameters are set, click Write Param.
After all parameters are set and written, the TF SERIES data works on Altitude Hold, Loiter and PosHold Mode. The data from the sensor will be used until you exceed RNGFND_MAX_CM,(which as our set is 12m) after that it switches to the barometer. Currently Lidar is not supported in Auto Mode。
Details are in Pic.6：
Pic. 6 Details for parameter setting
3.3 STM32 Trans Board Code
Receive and analyze the distance data from TF SERIES
// Global Variables
u16 distance = 0;
// Variables used by serial
static u8 Usart1buf[USART1_BUF_SIZE];
static u8 pointer = 0;
// Serial Port 1 Function Initialize
void USART1_Init(void)
{
USART_InitTypeDef USART1_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
// GPIOA Clock
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
// A9 -> TX , A10 -> RX
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9 | GPIO_Pin_10;
GPIO_InitStructure.GPIO_Speed = GPIO_High_Speed;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_Init(GPIOA,&GPIO_InitStructure);
// Alternative Function Configuration
GPIO_PinAFConfig(GPIOA,GPIO_PinSource9,GPIO_AF_USART1);
GPIO_PinAFConfig(GPIOA,GPIO_PinSource10,GPIO_AF_USART1);
// USART1 clock
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
// USART1 Interrupt Priority
NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
// USART1 Initialize
USART_DeInit(USART1);
USART1_InitStructure.USART_BaudRate = 115200;
USART1_InitStructure.USART_WordLength = USART_WordLength_8b;
USART1_InitStructure.USART_StopBits = USART_StopBits_1;
USART1_InitStructure.USART_Parity = USART_Parity_No;
USART1_InitStructure.USART_Mode = USART_Mode_Rx|USART_Mode_Tx;
USART1_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
USART_Init(USART1,&USART1_InitStructure);
USART_Cmd(USART1,ENABLE);
USART_ITConfig(USART1,USART_IT_RXNE,ENABLE);
}
// Serial Interrupt Function
void USART1_IRQHandler(void)
{
if(USART_GetITStatus(USART1, USART_IT_RXNE) != RESET
|| (USART_GetITStatus(USART1, USART_IT_ORE_RX) != RESET))
{
USART_ClearITPendingBit(USART1, USART_IT_RXNE);
Usart1buf[pointer++%USART1_BUF_SIZE] = USART_ReceiveData(USART1);
// Receive data program
if((pointer%USART1_BUF_SIZE >= 9))
{
// Check the head and the tail of the packet
// Better do a checksum, not written here
if( (Usart1buf[pointer%USART1_BUF_SIZE-3]==0x59)
&&(Usart1buf[pointer%USART1_BUF_SIZE-4]==0x59))
{
//Distance
distance=((u16)((Usart1buf[pointer%USART1_BUF_SIZE-1])8)
|(u16)(Usart1buf[pointer%USART1_BUF_SIZE-2]));
}
}
}
}
DAC Configuration
void DAC_Config(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
GPIO_Init(GPIOA, &GPIO_InitStructure);
DAC_InitTypeDef DAC_InitStructure;
DAC_DeInit();
DAC_InitStructure.DAC_Trigger = DAC_Trigger_Software;
DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;
DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Enable;
DAC_Init(DAC_Channel_1, &DAC_InitStructure);
DAC_Cmd(DAC_Channel_1,ENABLE);
DAC_SetChannel1Data(DAC_Align_12b_R,0x1fff);
DAC_SoftwareTriggerCmd(DAC_Channel_1,ENABLE);
}
Main function:
// The test height of TE-01 ,Unit mm
float test_height;
// Height bias, Unit mm
float bias = 180;
// Analog value output
s16 analog=0;
// Main
void main(void)
{
// Interrupt Group Configuration
NVIC_Config();
// Serial Initialize
USART1_Init();
// DAC Config
DAC_Config();
// Main Loop
while(1)
{
// Remove Bias
test_height = distance - bias;
// Data Conversion, 3V corresponding to the height of 12m, therefore
// test_height * 3.3 * 4096/（3 * 1200）= test_height * 4096 / 1320
analog = (s16)(test_height*4096/1320);
// Range Limit
analog = analog < 4095 ? analog : 4095;
analog = analog > 0 ? analog : 0;
// Voltage Output
DAC_SetChannel1Data(DAC_Align_12b_R,analog);
DAC_SoftwareTriggerCmd(DAC_Channel_1,ENABLE);
}
}
4. Data Test
In Flight Data of Mission Planner, Click Status below, find sonarrange(actual distance) and sonarvoltage(analog input voltage).
Pic 7 Distance Sensor Test (Test if the sensor gets readings correctly)
5. PID configuration
All PID configuration for PixHawk can be done on Mission Planner. See in http://ardupilot.org/copter/docs/common-tuning.html.
1. How does TF SERIES work on PixHawk
Lidar’s are used in flight modes which have height control, such as....
PixHawk interface for rangefinder are I2C , Analog， Serial. Details are on http://ardupilot.org/copter/docs/common-rangefinder-landingpage.html
2. Serial Mode
We recommend using Serial to send altitude signal to PixHawk.
Cautions: If you use serial, please update your firmware, make sure is newer than V 3.3.3.
2.1 Wire
Pic. 1(a) Connect TF SERIES to PixHawk via Serial
Pic. 1(b) Connect TF SERIES to PixHawk via Serial
2.2 Mission Planner
Connect Flight Controller to MP, click CONFIG/TUNING then select Full Parameter List change parameters as below:
- SERIAL4_PROTOCOL = 9 (Lidar)
- SERIAL4_BAUD = 115
- RNGFND_TYPE = 8 (LightWareSerial)
- RNGFND_SCALING = 1
- RNGFND_MIN_CM = 5
- RNGFND_MAX_CM = 1200
- RNGFND_GNDCLEAR = 5 unit cm, or you can use more specific value, it depends on the height TF SERIES installed.
See in Pic.2 and Pic.3
Pic.2 Serial parameter configuration
Pic.3 Serial parameter configuration
If Bad Lidar Health error occurs, please check if TF SERIES LiDAR window first, see whether TF SERIES emit red LED light. If there`s no red LED light, please check power supply. (Sometimes PixHawk have Serial 4/5 power supply issue) If there is LED light, please check if you wire the Serial correctly. If you still get this error message and got no reading in sonarrange/sonarvoltage, please connect TF01 to TELEM2 (like Pic.1(b))and change the Parameter for Serial 2 as below.
- SERIAL2_PROTOCOL = 9 (Lidar)
- SERIAL2_BAUD = 115
TF SERIES data is first send to a STM32 board and data is translated into AD data then sent to PixHawk.
Caution: TF SERIES, STM32 board and PixHawk shall share a common-ground.
Pic. 4 connect TF SERIES to PixHawk
3.1 Wire
Connect TF SERIES to input distance data using analog into PixHawk
Pic. 5 Analog input wire,
Red: 3.3V
Orange: AD analog signal
Black: GND
1
2
3
3.1
3.2 Mission Planner Configuration
Connect Flight controller to MP, select Full Parameter List in Config/Tuning, find and change the parameters below:
- RNGFND_PIN = “14” for PixHawk’s ADC 3.3v pin #2 OR “0” for APM2.x
- RNGFND_MAX_CM = “1200” (i.e. 12m max range)
- RNGFND_SCALING = “4” (i.e. 4m / 1v)
- RNGFND_TYPE = “1” (Analog)
When all parameters are set, click Write Param.
After all parameters are set and written, the TF SERIES data works on Altitude Hold, Loiter and PosHold Mode. The data from the sensor will be used until you exceed RNGFND_MAX_CM,(which as our set is 12m) after that it switches to the barometer. Currently Lidar is not supported in Auto Mode。
Details are in Pic.6：
Pic. 6 Details for parameter setting
3.3 STM32 Trans Board Code
Receive and analyze the distance data from TF SERIES
// Global Variables
u16 distance = 0;
// Variables used by serial
static u8 Usart1buf[USART1_BUF_SIZE];
static u8 pointer = 0;
// Serial Port 1 Function Initialize
void USART1_Init(void)
{
USART_InitTypeDef USART1_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
// GPIOA Clock
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
// A9 -> TX , A10 -> RX
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9 | GPIO_Pin_10;
GPIO_InitStructure.GPIO_Speed = GPIO_High_Speed;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_Init(GPIOA,&GPIO_InitStructure);
// Alternative Function Configuration
GPIO_PinAFConfig(GPIOA,GPIO_PinSource9,GPIO_AF_USART1);
GPIO_PinAFConfig(GPIOA,GPIO_PinSource10,GPIO_AF_USART1);
// USART1 clock
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
// USART1 Interrupt Priority
NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
// USART1 Initialize
USART_DeInit(USART1);
USART1_InitStructure.USART_BaudRate = 115200;
USART1_InitStructure.USART_WordLength = USART_WordLength_8b;
USART1_InitStructure.USART_StopBits = USART_StopBits_1;
USART1_InitStructure.USART_Parity = USART_Parity_No;
USART1_InitStructure.USART_Mode = USART_Mode_Rx|USART_Mode_Tx;
USART1_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
USART_Init(USART1,&USART1_InitStructure);
USART_Cmd(USART1,ENABLE);
USART_ITConfig(USART1,USART_IT_RXNE,ENABLE);
}
// Serial Interrupt Function
void USART1_IRQHandler(void)
{
if(USART_GetITStatus(USART1, USART_IT_RXNE) != RESET
|| (USART_GetITStatus(USART1, USART_IT_ORE_RX) != RESET))
{
USART_ClearITPendingBit(USART1, USART_IT_RXNE);
Usart1buf[pointer++%USART1_BUF_SIZE] = USART_ReceiveData(USART1);
// Receive data program
if((pointer%USART1_BUF_SIZE >= 9))
{
// Check the head and the tail of the packet
// Better do a checksum, not written here
if( (Usart1buf[pointer%USART1_BUF_SIZE-3]==0x59)
&&(Usart1buf[pointer%USART1_BUF_SIZE-4]==0x59))
{
//Distance
distance=((u16)((Usart1buf[pointer%USART1_BUF_SIZE-1])8)
|(u16)(Usart1buf[pointer%USART1_BUF_SIZE-2]));
}
}
}
}
DAC Configuration
void DAC_Config(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
GPIO_Init(GPIOA, &GPIO_InitStructure);
DAC_InitTypeDef DAC_InitStructure;
DAC_DeInit();
DAC_InitStructure.DAC_Trigger = DAC_Trigger_Software;
DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;
DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Enable;
DAC_Init(DAC_Channel_1, &DAC_InitStructure);
DAC_Cmd(DAC_Channel_1,ENABLE);
DAC_SetChannel1Data(DAC_Align_12b_R,0x1fff);
DAC_SoftwareTriggerCmd(DAC_Channel_1,ENABLE);
}
Main function:
// The test height of TE-01 ,Unit mm
float test_height;
// Height bias, Unit mm
float bias = 180;
// Analog value output
s16 analog=0;
// Main
void main(void)
{
// Interrupt Group Configuration
NVIC_Config();
// Serial Initialize
USART1_Init();
// DAC Config
DAC_Config();
// Main Loop
while(1)
{
// Remove Bias
test_height = distance - bias;
// Data Conversion, 3V corresponding to the height of 12m, therefore
// test_height * 3.3 * 4096/（3 * 1200）= test_height * 4096 / 1320
analog = (s16)(test_height*4096/1320);
// Range Limit
analog = analog < 4095 ? analog : 4095;
analog = analog > 0 ? analog : 0;
// Voltage Output
DAC_SetChannel1Data(DAC_Align_12b_R,analog);
DAC_SoftwareTriggerCmd(DAC_Channel_1,ENABLE);
}
}
4. Data Test
In Flight Data of Mission Planner, Click Status below, find sonarrange(actual distance) and sonarvoltage(analog input voltage).
Pic 7 Distance Sensor Test (Test if the sensor gets readings correctly)
5. PID configuration
All PID configuration for PixHawk can be done on Mission Planner. See in http://ardupilot.org/copter/docs/common-tuning.html.