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• Arcade Claw Machine - Room Sized

  Paul Gould • 08/07/2020 at 10:03 • 0 comments

  THe Brushless Actuators and GL5010 motors are used in Arcade Claw Machine - Room Sized project in the upper four corners of the room. Linked by RS485 communications. Limited to 2% Power.

  https://hackaday.io/project/173988-arcade-claw-machine-room-sized

• Software for hardware testing

  Paul Gould • 07/05/2020 at 16:05 • 2 comments

  Bootloader programmed using the SEGGER J-FLASH with the BIN file from Sparkfun SAMD21 Dev board bootloader. I will have to create my own custom one in the future. This will require using ATMEL studio which I do not like to use.

  After bootloader is programmed it can be seen as a USB port in the Arduino IDE. Set the board type to Sparkfun SAMD21 Dev and select the detected USB. The variants file has to be modified to disable the SER5 handler.

  Test software runs the following

  • Qwiic I2C OLED display
  • Reset Button and RX LED
  • SerialUSB.read and write
  • External SPI magnetic encoder
  • On-board SPI magnetic encoder
  • EEPROM I2C Read and write
  • Free running 6x Sequential ADC via DMA
  • DRV8305 
    • SPI Read and write registers
    • Fault and enable
    • 3x Current Monitor into ADC
    • PWM x3 Mode (not x6 Mode yet)
  • RS485 TX and direction (RX not tested yet)
  • On-board MOSFET Temperature sensor into ADC
  • Battery voltage Monitor into ADC

  Features left to test

  • Spare UART TX and RX
  • RS485 RX
  • FAN/Servo PWM output
  • External analogue temperature input

  Full operation test

  On-board magnetic encoder reads the diametric magnet connected to the motor shaft. Motor position is controlled from the USB using Saddle sinusoidal control. Vital information displayed on the OLED display.

• Assembled PCBs

  Paul Gould • 07/05/2020 at 15:29 • 0 comments

  Ordered the boards with assembly 18th June 2020 from JLCPCB in China and they arrived in Perth Australia 29th June 2020. There is a limited range of components available, so I had to order the remaining parts, mainly the connectors and sensors, from LSCS and Mouser.

  I made a mistake with the polarizing of the diodes because I didn't read the full JLC assembly notes.

  I made a mistake with the choice of the SM-regulator and dual power diode. Firstly the reg requires 6V to run the 3.3V supply for the SAMD21. This is fine when running of the external power supply but when operating for the USB this is not good. I reworked the boards with LMR14206 which operates from 4.5V. Which them leads onto the dual power diode. The one I chose has a voltage drop of 1V @ 30mA which is also not good from the USB supply. So a BAT721C can be used as the replacement. It has 0.4V drop at 100mA.

  The second mistake was using the DRV8305N which requires a VREG input voltage of 3.3V. I based the design on the DRV83053 which has an internal 3.3V regulator. The '3' cost twice as much at JLC than the 'N'. I just made a link between to the VREG pin from the closest 3.3V pad.

  The third mistake was with the pin multiplexing limitation of the RS485 TX and RX pins. These had to be swapped over. This required lifting two pins on the RS485 transceiver chip and adding some wire links.

  The fourth mistake was the spacing of the though holes of the fan/servo connector. It was designed for various pitch SMT and TH connectors but a 2.54mm 3pin servo connector wouldn't fit. 

• 5 Boards with Assembly are on order at JLC

  Paul Gould • 06/14/2020 at 16:19 • 5 comments

  Size 50mm square and 58mm round
  

  On board absolute magnetic encoder is either MA730, MA702, AS5147 or AS5047 There are others in this range.

  Connectors clockwise from the top

  • BLDC motor connectors & Power In/Out
  • External Motor Temp
  • qwiic
  • USB
  • Encoder SPI
  • Fan or Servo CTRL
  • RS485 in/out
  • RS485 out/in

  The connectors are multi footprint JST. Through hole straight / right angle, SMT straight / right angle

  Pitch can be either 1, 1.27, 1.5, 2 or 2.54mm

  Connectors on the back (from the bottom)
  

  • UART TTL
  • ISP to load the boot code
  • External Capacitor

• Redesigned for JLC PCB SMT assembly

  Paul Gould • 01/03/2020 at 13:14 • 4 comments

  JLC now do cheap PCB manufacture and SMT Assembly.

  I have changed the components to suit what is available at JLC https://jlcpcb.com/client/index.html#/parts

  ATSAMD21G18A-AU (CPU)

  DRV8305NPHPR (MOSFET Driver)

        with 3 Phase Current Sensor

  NVTFS5C453NL (N-MOSFETs 3x3mm 3mOhms 40V)

  MA730GQ-Z (Absolute Magnetic Encoder 14-bit SPI) or AS5xxx

  MP2359DJ-LF-Z (3V3 1A DC-DC Converter)

  SP3485EN-L/TR (RS485 comms)

  24LC01BT-I/OT (EEPROM for ID and parameter storage)

  STLM20W87F (Temperature Sensor for MOSFETs)

  Voltage monitor

  External Motor Temperature Connector

  Qwiic connector (I2C) for OLED display

  SPI Remote Encoder connector

  UART Connector

  Servo connector

  USB programming connector

  SWD programming connector (for putting in the Arduino Bootloader

  Reset Button (for getting it into the bootloader)

• The motor is turning

  Paul Gould • 08/21/2019 at 16:42 • 0 comments

  Git is now active

  https://github.com/gouldpa/FOC-Arduino-Brushless

• Actuator Operating System - Base Code

  Paul Gould • 08/03/2019 at 16:21 • 0 comments

  Arduino Code for SAMD21 Dev Breakout by Sparkfun

  https://www.sparkfun.com/products/13672?_ga=2.219677657.1904334046.1564414689-1081061511.1562028237

  Updated 2019-Aug-05

  Fixed DRV SPI CS; Added Test Points T0 & T1; Disabled Serial1

  Now on GIT https://github.com/gouldpa/FOC-Arduino-Brushless

  Don't use the code below, it will always be out of date

  /* External Encoder SPI
   * Motor Driver Control/Onboard Encoder SPI
   * 3 Phase timer with deadband TCC0
   * Timer IRQ 10KHz Timer 5
   * I2C Diaplay
   * RS485 with time-out Timer 4(start of packet)
   * ADC sequential, free-running (6) and DMA and IRQ
   * SerialUSB is available
   * Serial1 is available but is currently used as test points T0 and T1
   * 
   * Joint Control -> PID -> Motor Control (FOC) -> Three Phase Output
   */
  
  #include <SPI.h>
  #include "wiring_private.h" // pinPeripheral() function
  
  //  I2c OLED  ///////////////////////////////////////////////////////////
  #include "ssd1306.h" // library by Alexey Dynda
  char display_str[] = "1234567890";
  
  //  On-Board Encoder + Motor Driver and External Encoder /////////////////
  #define ENC_SPI_MISO 6 //29 D6 PA20 ser 5:2 SER
  #define ENC_SPI_SCK 7 // 30 D7 PA21 ser5:3 SER
  #define ENC_SPI_MOSI A5 //47 A5 PB02 ser5:0 ALT
  #define ENC_CS A0 //PA02
  #define ENC_CS_PORT_PIN PORT_PA02 // Fast Pin Switching REG_PORT_OUTSET0
  SPIClass ENC_SPI_5 (&sercom5, ENC_SPI_MISO,  ENC_SPI_SCK,  ENC_SPI_MOSI, SPI_PAD_0_SCK_3, SERCOM_RX_PAD_2); 
  
  #define DRV_SPI_MISO MISO // 21 PA12 SER4:0 ALT
  #define DRV_SPI_SCK SCK // 20 PB11 SER4:3 ALT
  #define DRV_SPI_MOSI MOSI //19 PB10 SER4:2 ALT
  #define DRV_CS 30 // PB22
  #define DRV_CS_PORT_PIN PORT_PB22 // Fast Pin Switching USE REG_PORT_OUTSET1
  SPIClass DRV_SPI_4 (&sercom4, DRV_SPI_MISO,  DRV_SPI_SCK,  DRV_SPI_MOSI, SPI_PAD_2_SCK_3, SERCOM_RX_PAD_0);
  
  uint16_t enc_data, drv_data; 
  
  //  Three Phase Center Aligned PWM with Dead-band //////////////////
  #define UH 3   //W1 14 PA09
  #define UL 5   //W5 24 PA15
  #define VH 10  //W2 27 PA18
  #define VL 11  //W6 25 PA16
  #define WH 12  //W3 28 PA19 
  #define WL 13  //W7 26 PA17
  
  //  RS485 Serial with Direction CTRL /////////////////////////////
  #define RS485_TX_SIZE 16
  #define RS485_RX_SIZE 32
  char RS485_txbuf[RS485_TX_SIZE];
  char RS485_rxbuf[RS485_RX_SIZE];
  #define RS485_RX_MAX 4
  #define RS485_TX_PACKET_SIZE 4
  #define UART_ERROR 0x80
  #define TX_COMPLETE 0x02
  #define RX_CHAR 0x04
  char RS485_tx_to_send=0;
  char RS485_tx_left=0;
  char RS485_rx_cnt=0;
  
  uint8_t i=0;
  
  #define RS485_RX 38 //PA13 ser2:1 ALT
  #define RS485_TX 4 //PA08 ser2:0 ALT
  #define RS485_DIR 2
  
  Uart Serial2 (&sercom2, RS485_RX, RS485_TX, SERCOM_RX_PAD_1, UART_TX_PAD_0);
  
  //  TC4 serial time-out //////////////////////////////////////////
  #define TC4_INTERRUPT 0 //Disable Interrupt 
  
  //  ADC DMA sequential free running (6) with Interrupts /////////////////
  #define ADCPIN1 A1
  #define ADC_Number 6
  
  #define HWORDS 7
  uint16_t adcbuf[HWORDS];     
  
  typedef struct {
      uint16_t btctrl;
      uint16_t btcnt;
      uint32_t srcaddr;
      uint32_t dstaddr;
      uint32_t descaddr;
  } dmacdescriptor ;
  volatile dmacdescriptor wrb[12] __attribute__ ((aligned (16)));
  dmacdescriptor descriptor_section[12] __attribute__ ((aligned (16)));
  dmacdescriptor descriptor __attribute__ ((aligned (16)));
  DmacDescriptor *desc; // DMA descriptor address (so we can change contents)
  
  static uint32_t ADC_DMA_chnl = 3;  // DMA channel
  
  
  
  /////          BLDC       //////////////////////////////////////////////////////////////////////////////////////
  
  int count;
  #define SIN_ARRAY_SIZE_BITS 12
  #define SIN_ARRAY_SIZE (1<<SIN_ARRAY_SIZE_BITS)
  #define MOTOR_POLE_PAIRS    7
  #define FULL_ANGLE 360.0
  #define DEG_RAD (3.1415/180.0)
  #define FULL_PWM_BITS 10
  #define FULL_PWM (1<<FULL_PWM_BITS)
  #define POS_ONE 0
  #define MAGNET_OFFSET -100 //0
  #define PHASE_OFFSET 120
  #define MAX_PWM 250
  
  /* Store in EEPROM
  #define CONFIG_ARRAY_SIZE 32
  int32 config_array[CONFIG_ARRAY_SIZE];
  
  #define ID_OS           0
  #define MAG_OFFSET_OS   1
  #define PHASE_OFFSET_OS 2
  #define TEMP_MAX_OS     3
  #define NOMINAL_OS      4
  #define NINETY_OS       5
  int current_config = 0;
  
  */
  int32_t...

  Read more »

• Software tasks

  Paul Gould • 04/30/2019 at 16:44 • 0 comments

  Low Level SAMD21 / Arduino functions with no libraries*

  1. Main OS timer - 100us (10KHz) IRQ                                                 (done)
  2. 3-Phase Motor Controller PWM with deadband                            (done)
     • (6-centre aligned pwms)                                                           (done)
  3. ADC- 6 channels sequential, semi-free-running DMA with IRQ     (done)
     • 3x Current Sensor
     • MOSFET Temperature Sensor
     • Battery Voltage
     • 1 Auxillary Analog Inputs
  4. Dual (same time) SPI (blocking and IRQ)                                             (done) 
  5. RS485 UART with IRQ (TX & RX)                                                        (done)
     1. with direction CTRL                                                                       (done)
     2. with time-out and packet start detect                                           (done)
  6. UART with DMA                                                                                  (attempted & fail)
  7. CPU's Internal EEPROM Emulation (Flash storage)                            (attempted & fail)
  8. External I2C EEPROM support (maybe Libraries)                             (not started, have eeprom)
  9. I2C OLED support (with Libraries)                                                     (done)
     
  10. SerialUSB with above                                                                         (done)
  11. Serial1 with above                                                                              (done)
  12. Making all the Low level features work together                         (done, done and done)

  High Level Functions

  1. Field Orientated Control (FOC) & Motor Commutation                    (done)
  2. PID Joint Control                                                                                 (done, but just P)
  3. RS485 Packet Structure                                 ...

  Read more »

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