import abc import random import threading import time from typing import Callable import dynamixel_sdk as dxl import serial from mock_serial.mock_serial import MockSerial, Stub from lerobot.common.motors.dynamixel import X_SERIES_CONTROL_TABLE, DynamixelMotorsBus # https://emanual.robotis.com/docs/en/dxl/crc/ DXL_CRC_TABLE = [ 0x0000, 0x8005, 0x800F, 0x000A, 0x801B, 0x001E, 0x0014, 0x8011, 0x8033, 0x0036, 0x003C, 0x8039, 0x0028, 0x802D, 0x8027, 0x0022, 0x8063, 0x0066, 0x006C, 0x8069, 0x0078, 0x807D, 0x8077, 0x0072, 0x0050, 0x8055, 0x805F, 0x005A, 0x804B, 0x004E, 0x0044, 0x8041, 0x80C3, 0x00C6, 0x00CC, 0x80C9, 0x00D8, 0x80DD, 0x80D7, 0x00D2, 0x00F0, 0x80F5, 0x80FF, 0x00FA, 0x80EB, 0x00EE, 0x00E4, 0x80E1, 0x00A0, 0x80A5, 0x80AF, 0x00AA, 0x80BB, 0x00BE, 0x00B4, 0x80B1, 0x8093, 0x0096, 0x009C, 0x8099, 0x0088, 0x808D, 0x8087, 0x0082, 0x8183, 0x0186, 0x018C, 0x8189, 0x0198, 0x819D, 0x8197, 0x0192, 0x01B0, 0x81B5, 0x81BF, 0x01BA, 0x81AB, 0x01AE, 0x01A4, 0x81A1, 0x01E0, 0x81E5, 0x81EF, 0x01EA, 0x81FB, 0x01FE, 0x01F4, 0x81F1, 0x81D3, 0x01D6, 0x01DC, 0x81D9, 0x01C8, 0x81CD, 0x81C7, 0x01C2, 0x0140, 0x8145, 0x814F, 0x014A, 0x815B, 0x015E, 0x0154, 0x8151, 0x8173, 0x0176, 0x017C, 0x8179, 0x0168, 0x816D, 0x8167, 0x0162, 0x8123, 0x0126, 0x012C, 0x8129, 0x0138, 0x813D, 0x8137, 0x0132, 0x0110, 0x8115, 0x811F, 0x011A, 0x810B, 0x010E, 0x0104, 0x8101, 0x8303, 0x0306, 0x030C, 0x8309, 0x0318, 0x831D, 0x8317, 0x0312, 0x0330, 0x8335, 0x833F, 0x033A, 0x832B, 0x032E, 0x0324, 0x8321, 0x0360, 0x8365, 0x836F, 0x036A, 0x837B, 0x037E, 0x0374, 0x8371, 0x8353, 0x0356, 0x035C, 0x8359, 0x0348, 0x834D, 0x8347, 0x0342, 0x03C0, 0x83C5, 0x83CF, 0x03CA, 0x83DB, 0x03DE, 0x03D4, 0x83D1, 0x83F3, 0x03F6, 0x03FC, 0x83F9, 0x03E8, 0x83ED, 0x83E7, 0x03E2, 0x83A3, 0x03A6, 0x03AC, 0x83A9, 0x03B8, 0x83BD, 0x83B7, 0x03B2, 0x0390, 0x8395, 0x839F, 0x039A, 0x838B, 0x038E, 0x0384, 0x8381, 0x0280, 0x8285, 0x828F, 0x028A, 0x829B, 0x029E, 0x0294, 0x8291, 0x82B3, 0x02B6, 0x02BC, 0x82B9, 0x02A8, 0x82AD, 0x82A7, 0x02A2, 0x82E3, 0x02E6, 0x02EC, 0x82E9, 0x02F8, 0x82FD, 0x82F7, 0x02F2, 0x02D0, 0x82D5, 0x82DF, 0x02DA, 0x82CB, 0x02CE, 0x02C4, 0x82C1, 0x8243, 0x0246, 0x024C, 0x8249, 0x0258, 0x825D, 0x8257, 0x0252, 0x0270, 0x8275, 0x827F, 0x027A, 0x826B, 0x026E, 0x0264, 0x8261, 0x0220, 0x8225, 0x822F, 0x022A, 0x823B, 0x023E, 0x0234, 0x8231, 0x8213, 0x0216, 0x021C, 0x8219, 0x0208, 0x820D, 0x8207, 0x0202 ] # fmt: skip # https://emanual.robotis.com/docs/en/dxl/protocol2/#instruction INSTRUCTION_TYPES = { "Ping": 0x01, # Checks whether the Packet has arrived at a device with the same ID as the specified packet ID "Read": 0x02, # Read data from the Device "Write": 0x03, # Write data to the Device "Reg_Write": 0x04, # Register the Instruction Packet in standby status; Packet can later be executed using the Action command "Action": 0x05, # Executes a Packet that was registered beforehand using Reg Write "Factory_Reset": 0x06, # Resets the Control Table to its initial factory default settings "Reboot": 0x08, # Reboot the Device "Clear": 0x10, # Reset certain information stored in memory "Control_Table_Backup": 0x20, # Store current Control Table status data to a Backup or to restore backup EEPROM data. "Status": 0x55, # Return packet sent following the execution of an Instruction Packet "Sync_Read": 0x82, # Read data from multiple devices with the same Address with the same length at once "Sync_Write": 0x83, # Write data to multiple devices with the same Address with the same length at once "Fast_Sync_Read": 0x8A, # Read data from multiple devices with the same Address with the same length at once "Bulk_Read": 0x92, # Read data from multiple devices with different Addresses with different lengths at once "Bulk_Write": 0x93, # Write data to multiple devices with different Addresses with different lengths at once "Fast_Bulk_Read": 0x9A, # Read data from multiple devices with different Addresses with different lengths at once } # fmt: skip # https://emanual.robotis.com/docs/en/dxl/protocol2/#error ERROR_TYPE = { "Success": 0x00, # No error "Result_Fail": 0x01, # Failed to process the sent Instruction Packet "Instruction_Error": 0x02, # An undefined Instruction has been usedAction has been used without Reg Write "CRC_Error": 0x03, # The CRC of the sent Packet does not match the expected value "Data_Range_Error": 0x04, # Data to be written to the specified Address is outside the range of the minimum/maximum value "Data_Length_Error": 0x05, # Attempted to write Data that is shorter than the required data length of the specified Address # (ex: when you attempt to only use 2 bytes of a register that has been defined as 4 bytes) "Data_Limit_Error": 0x06, # Data to be written to the specified Address is outside of the configured Limit value "Access_Error": 0x07, # Attempted to write a value to an Address that is Read Only or has not been defined # Attempted to read a value from an Address that is Write Only or has not been defined # Attempted to write a value to an EEPROM register while Torque was Enabled. } # fmt: skip class MockDynamixelPacketv2(abc.ABC): @classmethod def build(cls, dxl_id: int, params: list[int], length: list[int], *args, **kwargs) -> bytes: packet = cls._build(dxl_id, params, length, *args, **kwargs) packet = cls._add_stuffing(packet) packet = cls._add_crc(packet) return bytes(packet) @abc.abstractclassmethod def _build(cls, dxl_id: int, params: list[int], length: int, *args, **kwargs) -> list[int]: pass @staticmethod def _add_stuffing(packet: list[int]) -> list[int]: """ Byte stuffing is a method of adding additional data to generated instruction packets to ensure that the packets are processed successfully. When the byte pattern "0xFF 0xFF 0xFD" appears in a packet, byte stuffing adds 0xFD to the end of the pattern to convert it to “0xFF 0xFF 0xFD 0xFD” to ensure that it is not interpreted as the header at the start of another packet. Source: https://emanual.robotis.com/docs/en/dxl/protocol2/#transmission-process Args: packet (list[int]): The raw packet without stuffing. Returns: list[int]: The packet stuffed if it contained a "0xFF 0xFF 0xFD" byte sequence in its data bytes. """ packet_length_in = dxl.DXL_MAKEWORD(packet[dxl.PKT_LENGTH_L], packet[dxl.PKT_LENGTH_H]) packet_length_out = packet_length_in temp = [0] * dxl.TXPACKET_MAX_LEN # FF FF FD XX ID LEN_L LEN_H temp[dxl.PKT_HEADER0 : dxl.PKT_HEADER0 + dxl.PKT_LENGTH_H + 1] = packet[ dxl.PKT_HEADER0 : dxl.PKT_HEADER0 + dxl.PKT_LENGTH_H + 1 ] index = dxl.PKT_INSTRUCTION for i in range(0, packet_length_in - 2): # except CRC temp[index] = packet[i + dxl.PKT_INSTRUCTION] index = index + 1 if ( packet[i + dxl.PKT_INSTRUCTION] == 0xFD and packet[i + dxl.PKT_INSTRUCTION - 1] == 0xFF and packet[i + dxl.PKT_INSTRUCTION - 2] == 0xFF ): # FF FF FD temp[index] = 0xFD index = index + 1 packet_length_out = packet_length_out + 1 temp[index] = packet[dxl.PKT_INSTRUCTION + packet_length_in - 2] temp[index + 1] = packet[dxl.PKT_INSTRUCTION + packet_length_in - 1] index = index + 2 if packet_length_in != packet_length_out: packet = [0] * index packet[0:index] = temp[0:index] packet[dxl.PKT_LENGTH_L] = dxl.DXL_LOBYTE(packet_length_out) packet[dxl.PKT_LENGTH_H] = dxl.DXL_HIBYTE(packet_length_out) return packet @staticmethod def _add_crc(packet: list[int]) -> list[int]: """Computes and add CRC to the packet. https://emanual.robotis.com/docs/en/dxl/crc/ https://en.wikipedia.org/wiki/Cyclic_redundancy_check Args: packet (list[int]): The raw packet without CRC (but with placeholders for it). Returns: list[int]: The raw packet with a valid CRC. """ crc = 0 for j in range(len(packet) - 2): i = ((crc >> 8) ^ packet[j]) & 0xFF crc = ((crc << 8) ^ DXL_CRC_TABLE[i]) & 0xFFFF packet[-2] = dxl.DXL_LOBYTE(crc) packet[-1] = dxl.DXL_HIBYTE(crc) return packet class MockInstructionPacket(MockDynamixelPacketv2): """ Helper class to build valid Dynamixel Protocol 2.0 Instruction Packets. Protocol 2.0 Instruction Packet structure (from https://emanual.robotis.com/docs/en/dxl/protocol2/#instruction-packet) | Header | Packet ID | Length | Instruction | Params | CRC | | ------------------- | --------- | ----------- | ----------- | ----------------- | ----------- | | 0xFF 0xFF 0xFD 0x00 | ID | Len_L Len_H | Instr | Param 1 … Param N | CRC_L CRC_H | """ @classmethod def _build(cls, dxl_id: int, params: list[int], length: int, instruct_type: str) -> list[int]: instruct_value = INSTRUCTION_TYPES[instruct_type] return [ 0xFF, 0xFF, 0xFD, 0x00, # header dxl_id, # servo id dxl.DXL_LOBYTE(length), # length_l dxl.DXL_HIBYTE(length), # length_h instruct_value, # instruction type *params, # data bytes 0x00, 0x00 # placeholder for CRC ] # fmt: skip @classmethod def ping( cls, dxl_id: int, ) -> bytes: """ Builds a "Ping" broadcast instruction. (from https://emanual.robotis.com/docs/en/dxl/protocol2/#ping-0x01) No parameters required. """ params, length = [], 3 return cls.build(dxl_id=dxl_id, params=params, length=length, instruct_type="Ping") @classmethod def sync_read( cls, dxl_ids: list[int], start_address: int, data_length: int, ) -> bytes: """ Builds a "Sync_Read" broadcast instruction. (from https://emanual.robotis.com/docs/en/dxl/protocol2/#sync-read-0x82) The parameters for Sync_Read (Protocol 2.0) are: param[0] = start_address L param[1] = start_address H param[2] = data_length L param[3] = data_length H param[4+] = motor IDs to read from And 'length' = (number_of_params + 7), where: +1 is for instruction byte, +2 is for the address bytes, +2 is for the length bytes, +2 is for the CRC at the end. """ params = [ dxl.DXL_LOBYTE(start_address), dxl.DXL_HIBYTE(start_address), dxl.DXL_LOBYTE(data_length), dxl.DXL_HIBYTE(data_length), *dxl_ids, ] length = len(dxl_ids) + 7 return cls.build(dxl_id=dxl.BROADCAST_ID, params=params, length=length, instruct_type="Sync_Read") @classmethod def sync_write( cls, ids_values: dict[int], start_address: int, data_length: int, ) -> bytes: """ Builds a "Sync_Write" broadcast instruction. (from https://emanual.robotis.com/docs/en/dxl/protocol2/#sync-write-0x83) The parameters for Sync_Write (Protocol 2.0) are: param[0] = start_address L param[1] = start_address H param[2] = data_length L param[3] = data_length H param[5] = [1st motor] ID param[5+1] = [1st motor] 1st Byte param[5+2] = [1st motor] 2nd Byte ... param[5+X] = [1st motor] X-th Byte param[6] = [2nd motor] ID param[6+1] = [2nd motor] 1st Byte param[6+2] = [2nd motor] 2nd Byte ... param[6+X] = [2nd motor] X-th Byte And 'length' = ((number_of_params * 1 + data_length) + 7), where: +1 is for instruction byte, +2 is for the address bytes, +2 is for the length bytes, +2 is for the CRC at the end. """ data = [] for idx, value in ids_values.items(): split_value = DynamixelMotorsBus.split_int_bytes(value, data_length) data += [idx, *split_value] params = [ dxl.DXL_LOBYTE(start_address), dxl.DXL_HIBYTE(start_address), dxl.DXL_LOBYTE(data_length), dxl.DXL_HIBYTE(data_length), *data, ] length = len(ids_values) * (1 + data_length) + 7 return cls.build(dxl_id=dxl.BROADCAST_ID, params=params, length=length, instruct_type="Sync_Write") class MockStatusPacket(MockDynamixelPacketv2): """ Helper class to build valid Dynamixel Protocol 2.0 Status Packets. Protocol 2.0 Status Packet structure (from https://emanual.robotis.com/docs/en/dxl/protocol2/#status-packet) | Header | Packet ID | Length | Instruction | Error | Params | CRC | | ------------------- | --------- | ----------- | ----------- | ----- | ----------------- | ----------- | | 0xFF 0xFF 0xFD 0x00 | ID | Len_L Len_H | 0x55 | Err | Param 1 … Param N | CRC_L CRC_H | """ @classmethod def _build(cls, dxl_id: int, params: list[int], length: int, error: str = "Success") -> list[int]: err_byte = ERROR_TYPE[error] return [ 0xFF, 0xFF, 0xFD, 0x00, # header dxl_id, # servo id dxl.DXL_LOBYTE(length), # length_l dxl.DXL_HIBYTE(length), # length_h 0x55, # instruction = 'status' err_byte, # error *params, # data bytes 0x00, 0x00 # placeholder for CRC ] # fmt: skip @classmethod def ping(cls, dxl_id: int, model_nb: int = 1190, firm_ver: int = 50) -> bytes: """Builds a 'Ping' status packet. https://emanual.robotis.com/docs/en/dxl/protocol2/#ping-0x01 Args: dxl_id (int): ID of the servo responding. model_nb (int, optional): Desired 'model number' to be returned in the packet. Defaults to 1190 which corresponds to a XL330-M077-T. firm_ver (int, optional): Desired 'firmware version' to be returned in the packet. Defaults to 50. Returns: bytes: The raw 'Ping' status packet ready to be sent through serial. """ params = [dxl.DXL_LOBYTE(model_nb), dxl.DXL_HIBYTE(model_nb), firm_ver] length = 7 return cls.build(dxl_id, params=params, length=length) @classmethod def present_position(cls, dxl_id: int, pos: int | None = None, min_max_range: tuple = (0, 4095)) -> bytes: """Builds a 'Present_Position' status packet. Args: dxl_id (int): Servo id pos (int | None, optional): Desired 'Present_Position' to be returned in the packet. If None, it will use a random value in the min_max_range. Defaults to None. min_max_range (tuple, optional): Min/max range to generate the position values used for when 'pos' is None. Note that the bounds are included in the range. Defaults to (0, 4095). Returns: bytes: The raw 'Present_Position' status packet ready to be sent through serial. """ pos = random.randint(*min_max_range) if pos is None else pos params = [dxl.DXL_LOBYTE(pos), dxl.DXL_HIBYTE(pos), 0, 0] length = 8 return cls.build(dxl_id, params=params, length=length) class MockPortHandler(dxl.PortHandler): """ This class overwrite the 'setupPort' method of the Dynamixel PortHandler because it can specify baudrates that are not supported with a serial port on MacOS. """ def setupPort(self, cflag_baud): # noqa: N802 if self.is_open: self.closePort() self.ser = serial.Serial( port=self.port_name, # baudrate=self.baudrate, <- This will fail on MacOS # parity = serial.PARITY_ODD, # stopbits = serial.STOPBITS_TWO, bytesize=serial.EIGHTBITS, timeout=0, ) self.is_open = True self.ser.reset_input_buffer() self.tx_time_per_byte = (1000.0 / self.baudrate) * 10.0 return True class WaitableStub(Stub): """ In some situations, a test might be checking if a stub has been called before `MockSerial` thread had time to read, match, and call the stub. In these situations, the test can fail randomly. Use `wait_called()` or `wait_calls()` to block until the stub is called, avoiding race conditions. """ def __init__(self, **kwargs): super().__init__(**kwargs) self._event = threading.Event() def call(self): self._event.set() return super().call() def wait_called(self, timeout: float = 1.0): return self._event.wait(timeout) def wait_calls(self, min_calls: int = 1, timeout: float = 1.0): start = time.perf_counter() while time.perf_counter() - start < timeout: if self.calls >= min_calls: return self.calls time.sleep(0.005) raise TimeoutError(f"Stub not called {min_calls} times within {timeout} seconds.") class MockMotors(MockSerial): """ This class will simulate physical motors by responding with valid status packets upon receiving some instruction packets. It is meant to test MotorsBus classes. """ ctrl_table = X_SERIES_CONTROL_TABLE def __init__(self): super().__init__() self.open() @property def stubs(self) -> dict[str, WaitableStub]: return super().stubs def stub(self, *, name=None, **kwargs): new_stub = WaitableStub(**kwargs) self._MockSerial__stubs[name or new_stub.receive_bytes] = new_stub return new_stub def build_broadcast_ping_stub( self, ids_models_firmwares: dict[int, list[int]] | None = None, num_invalid_try: int = 0 ) -> str: ping_request = MockInstructionPacket.ping(dxl.BROADCAST_ID) return_packets = b"".join( MockStatusPacket.ping(idx, model, firm_ver) for idx, (model, firm_ver) in ids_models_firmwares.items() ) ping_response = self._build_send_fn(return_packets, num_invalid_try) stub_name = "Ping_" + "_".join([str(idx) for idx in ids_models_firmwares]) self.stub( name=stub_name, receive_bytes=ping_request, send_fn=ping_response, ) return stub_name def build_ping_stub( self, dxl_id: int, model_nb: int, firm_ver: int = 50, num_invalid_try: int = 0 ) -> str: ping_request = MockInstructionPacket.ping(dxl_id) return_packet = MockStatusPacket.ping(dxl_id, model_nb, firm_ver) ping_response = self._build_send_fn(return_packet, num_invalid_try) stub_name = f"Ping_{dxl_id}" self.stub( name=stub_name, receive_bytes=ping_request, send_fn=ping_response, ) return stub_name def build_sync_read_stub( self, data_name: str, ids_values: dict[int, int] | None = None, num_invalid_try: int = 0 ) -> str: """ 'data_name' supported: - Present_Position """ address, length = self.ctrl_table[data_name] sync_read_request = MockInstructionPacket.sync_read(list(ids_values), address, length) if data_name != "Present_Position": raise NotImplementedError return_packets = b"".join( MockStatusPacket.present_position(idx, pos) for idx, pos in ids_values.items() ) sync_read_response = self._build_send_fn(return_packets, num_invalid_try) stub_name = f"Sync_Read_{data_name}_" + "_".join([str(idx) for idx in ids_values]) self.stub( name=stub_name, receive_bytes=sync_read_request, send_fn=sync_read_response, ) return stub_name def build_sync_write_stub( self, data_name: str, ids_values: dict[int, int] | None = None, num_invalid_try: int = 0 ) -> str: address, length = self.ctrl_table[data_name] sync_read_request = MockInstructionPacket.sync_write(ids_values, address, length) # if data_name != "Goal_Position": # raise NotImplementedError stub_name = f"Sync_Write_{data_name}_" + "_".join([str(idx) for idx in ids_values]) self.stub( name=stub_name, receive_bytes=sync_read_request, send_fn=self._build_send_fn(b"", num_invalid_try), ) return stub_name @staticmethod def _build_send_fn(packet: bytes, num_invalid_try: int = 0) -> Callable[[int], bytes]: def send_fn(_call_count: int) -> bytes: if num_invalid_try >= _call_count: return b"" return packet return send_fn