hybridgroup.gobot/platforms/sphero/sphero_driver.go

405 lines
11 KiB
Go

package sphero
import (
"bytes"
"encoding/binary"
"errors"
"time"
"github.com/hybridgroup/gobot"
)
const (
SensorData = "sensordata"
Collision = "collision"
Error = "error"
)
type packet struct {
header []uint8
body []uint8
checksum uint8
}
// Represents a Sphero
type SpheroDriver struct {
name string
connection gobot.Connection
seq uint8
asyncResponse [][]uint8
syncResponse [][]uint8
packetChannel chan *packet
responseChannel chan []uint8
gobot.Eventer
gobot.Commander
}
// NewSpheroDriver returns a new SpheroDriver given a SpheroAdaptor and name.
//
// Adds the following API Commands:
// "ConfigureLocator" - See SpheroDriver.ConfigureLocator
// "Roll" - See SpheroDriver.Roll
// "Stop" - See SpheroDriver.Stop
// "GetRGB" - See SpheroDriver.GetRGB
// "ReadLocator" - See SpheroDriver.ReadLocator
// "SetBackLED" - See SpheroDriver.SetBackLED
// "SetHeading" - See SpheroDriver.SetHeading
// "SetStabilization" - See SpheroDriver.SetStabilization
// "SetDataStreaming" - See SpheroDriver.SetDataStreaming
// "SetRotationRate" - See SpheroDriver.SetRotationRate
func NewSpheroDriver(a *SpheroAdaptor, name string) *SpheroDriver {
s := &SpheroDriver{
name: name,
connection: a,
Eventer: gobot.NewEventer(),
Commander: gobot.NewCommander(),
packetChannel: make(chan *packet, 1024),
responseChannel: make(chan []uint8, 1024),
}
s.AddEvent(Error)
s.AddEvent(Collision)
s.AddEvent(SensorData)
s.AddCommand("SetRGB", func(params map[string]interface{}) interface{} {
r := uint8(params["r"].(float64))
g := uint8(params["g"].(float64))
b := uint8(params["b"].(float64))
s.SetRGB(r, g, b)
return nil
})
s.AddCommand("Roll", func(params map[string]interface{}) interface{} {
speed := uint8(params["speed"].(float64))
heading := uint16(params["heading"].(float64))
s.Roll(speed, heading)
return nil
})
s.AddCommand("Stop", func(params map[string]interface{}) interface{} {
s.Stop()
return nil
})
s.AddCommand("GetRGB", func(params map[string]interface{}) interface{} {
return s.GetRGB()
})
s.AddCommand("ReadLocator", func(params map[string]interface{}) interface{} {
return s.ReadLocator()
})
s.AddCommand("SetBackLED", func(params map[string]interface{}) interface{} {
level := uint8(params["level"].(float64))
s.SetBackLED(level)
return nil
})
s.AddCommand("SetRotationRate", func(params map[string]interface{}) interface{} {
level := uint8(params["level"].(float64))
s.SetRotationRate(level)
return nil
})
s.AddCommand("SetHeading", func(params map[string]interface{}) interface{} {
heading := uint16(params["heading"].(float64))
s.SetHeading(heading)
return nil
})
s.AddCommand("SetStabilization", func(params map[string]interface{}) interface{} {
on := params["enable"].(bool)
s.SetStabilization(on)
return nil
})
s.AddCommand("SetDataStreaming", func(params map[string]interface{}) interface{} {
N := uint16(params["N"].(float64))
M := uint16(params["M"].(float64))
Mask := uint32(params["Mask"].(float64))
Pcnt := uint8(params["Pcnt"].(float64))
Mask2 := uint32(params["Mask2"].(float64))
s.SetDataStreaming(DataStreamingConfig{N: N, M: M, Mask2: Mask2, Pcnt: Pcnt, Mask: Mask})
return nil
})
s.AddCommand("ConfigureLocator", func(params map[string]interface{}) interface{} {
Flags := uint8(params["Flags"].(float64))
X := int16(params["X"].(float64))
Y := int16(params["Y"].(float64))
YawTare := int16(params["YawTare"].(float64))
s.ConfigureLocator(LocatorConfig{Flags: Flags, X: X, Y: Y, YawTare: YawTare})
return nil
})
return s
}
func (s *SpheroDriver) Name() string { return s.name }
func (s *SpheroDriver) Connection() gobot.Connection { return s.connection }
func (s *SpheroDriver) adaptor() *SpheroAdaptor {
return s.Connection().(*SpheroAdaptor)
}
// Start starts the SpheroDriver and enables Collision Detection.
// Returns true on successful start.
//
// Emits the Events:
// Collision sphero.CollisionPacket - On Collision Detected
// SensorData sphero.DataStreamingPacket - On Data Streaming event
// Error error- On error while processing asynchronous response
func (s *SpheroDriver) Start() (errs []error) {
go func() {
for {
packet := <-s.packetChannel
err := s.write(packet)
if err != nil {
gobot.Publish(s.Event(Error), err)
}
}
}()
go func() {
for {
response := <-s.responseChannel
s.syncResponse = append(s.syncResponse, response)
}
}()
go func() {
for {
header := s.readHeader()
if len(header) > 0 {
body := s.readBody(header[4])
data := append(header, body...)
checksum := data[len(data)-1]
if checksum != calculateChecksum(data[2:len(data)-1]) {
continue
}
switch header[1] {
case 0xFE:
s.asyncResponse = append(s.asyncResponse, data)
case 0xFF:
s.responseChannel <- data
}
}
}
}()
go func() {
for {
var evt []uint8
for len(s.asyncResponse) != 0 {
evt, s.asyncResponse = s.asyncResponse[len(s.asyncResponse)-1], s.asyncResponse[:len(s.asyncResponse)-1]
if evt[2] == 0x07 {
s.handleCollisionDetected(evt)
} else if evt[2] == 0x03 {
s.handleDataStreaming(evt)
}
}
time.Sleep(100 * time.Millisecond)
}
}()
s.ConfigureCollisionDetection(DefaultCollisionConfig())
s.enableStopOnDisconnect()
return
}
// Halt halts the SpheroDriver and sends a SpheroDriver.Stop command to the Sphero.
// Returns true on successful halt.
func (s *SpheroDriver) Halt() (errs []error) {
if s.adaptor().connected {
gobot.Every(10*time.Millisecond, func() {
s.Stop()
})
time.Sleep(1 * time.Second)
}
return
}
// SetRGB sets the Sphero to the given r, g, and b values
func (s *SpheroDriver) SetRGB(r uint8, g uint8, b uint8) {
s.packetChannel <- s.craftPacket([]uint8{r, g, b, 0x01}, 0x02, 0x20)
}
// GetRGB returns the current r, g, b value of the Sphero
func (s *SpheroDriver) GetRGB() []uint8 {
buf := s.getSyncResponse(s.craftPacket([]uint8{}, 0x02, 0x22))
if len(buf) == 9 {
return []uint8{buf[5], buf[6], buf[7]}
}
return []uint8{}
}
// ReadLocator reads Sphero's current position (X,Y), component velocities and SOG (speed over ground).
func (s *SpheroDriver) ReadLocator() []int16 {
buf := s.getSyncResponse(s.craftPacket([]uint8{}, 0x02, 0x15))
if len(buf) == 16 {
vals := make([]int16, 5)
_ = binary.Read(bytes.NewReader(buf[5:15]), binary.BigEndian, &vals)
return vals
}
return []int16{}
}
// SetBackLED sets the Sphero Back LED to the specified brightness
func (s *SpheroDriver) SetBackLED(level uint8) {
s.packetChannel <- s.craftPacket([]uint8{level}, 0x02, 0x21)
}
// SetRotationRate sets the Sphero rotation rate
// A value of 255 jumps to the maximum (currently 400 degrees/sec).
func (s *SpheroDriver) SetRotationRate(level uint8) {
s.packetChannel <- s.craftPacket([]uint8{level}, 0x02, 0x03)
}
// SetHeading sets the heading of the Sphero
func (s *SpheroDriver) SetHeading(heading uint16) {
s.packetChannel <- s.craftPacket([]uint8{uint8(heading >> 8), uint8(heading & 0xFF)}, 0x02, 0x01)
}
// SetStabilization enables or disables the built-in auto stabilizing features of the Sphero
func (s *SpheroDriver) SetStabilization(on bool) {
b := uint8(0x01)
if !on {
b = 0x00
}
s.packetChannel <- s.craftPacket([]uint8{b}, 0x02, 0x02)
}
// Roll sends a roll command to the Sphero gives a speed and heading
func (s *SpheroDriver) Roll(speed uint8, heading uint16) {
s.packetChannel <- s.craftPacket([]uint8{speed, uint8(heading >> 8), uint8(heading & 0xFF), 0x01}, 0x02, 0x30)
}
// Configures and enables the Locator
func (s *SpheroDriver) ConfigureLocator(d LocatorConfig) {
buf := new(bytes.Buffer)
binary.Write(buf, binary.BigEndian, d)
s.packetChannel <- s.craftPacket(buf.Bytes(), 0x02, 0x13)
}
// Enables sensor data streaming
func (s *SpheroDriver) SetDataStreaming(d DataStreamingConfig) {
buf := new(bytes.Buffer)
binary.Write(buf, binary.BigEndian, d)
s.packetChannel <- s.craftPacket(buf.Bytes(), 0x02, 0x11)
}
// Stop sets the Sphero to a roll speed of 0
func (s *SpheroDriver) Stop() {
s.Roll(0, 0)
}
// ConfigureCollisionDetection configures the sensitivity of the detection.
func (s *SpheroDriver) ConfigureCollisionDetection(cc CollisionConfig) {
s.packetChannel <- s.craftPacket([]uint8{cc.Method, cc.Xt, cc.Yt, cc.Xs, cc.Ys, cc.Dead}, 0x02, 0x12)
}
func (s *SpheroDriver) enableStopOnDisconnect() {
s.packetChannel <- s.craftPacket([]uint8{0x00, 0x00, 0x00, 0x01}, 0x02, 0x37)
}
func (s *SpheroDriver) handleCollisionDetected(data []uint8) {
// ensure data is the right length:
if len(data) != 22 || data[4] != 17 {
return
}
var collision CollisionPacket
buffer := bytes.NewBuffer(data[5:]) // skip header
binary.Read(buffer, binary.BigEndian, &collision)
gobot.Publish(s.Event(Collision), collision)
}
func (s *SpheroDriver) handleDataStreaming(data []uint8) {
// ensure data is the right length:
if len(data) != 90 {
return
}
var dataPacket DataStreamingPacket
buffer := bytes.NewBuffer(data[5:]) // skip header
binary.Read(buffer, binary.BigEndian, &dataPacket)
gobot.Publish(s.Event(SensorData), dataPacket)
}
func (s *SpheroDriver) getSyncResponse(packet *packet) []byte {
s.packetChannel <- packet
for i := 0; i < 500; i++ {
for key := range s.syncResponse {
if s.syncResponse[key][3] == packet.header[4] && len(s.syncResponse[key]) > 6 {
var response []byte
response, s.syncResponse = s.syncResponse[len(s.syncResponse)-1], s.syncResponse[:len(s.syncResponse)-1]
return response
}
}
time.Sleep(100 * time.Microsecond)
}
return []byte{}
}
func (s *SpheroDriver) craftPacket(body []uint8, did byte, cid byte) *packet {
packet := new(packet)
packet.body = body
dlen := len(packet.body) + 1
packet.header = []uint8{0xFF, 0xFF, did, cid, s.seq, uint8(dlen)}
packet.checksum = s.calculateChecksum(packet)
return packet
}
func (s *SpheroDriver) write(packet *packet) (err error) {
buf := append(packet.header, packet.body...)
buf = append(buf, packet.checksum)
length, err := s.adaptor().sp.Write(buf)
if err != nil {
return err
} else if length != len(buf) {
return errors.New("Not enough bytes written")
}
s.seq++
return
}
func (s *SpheroDriver) calculateChecksum(packet *packet) uint8 {
buf := append(packet.header, packet.body...)
return calculateChecksum(buf[2:])
}
func calculateChecksum(buf []byte) byte {
var calculatedChecksum uint16
for i := range buf {
calculatedChecksum += uint16(buf[i])
}
return uint8(^(calculatedChecksum % 256))
}
func (s *SpheroDriver) readHeader() []uint8 {
return s.readNextChunk(5)
}
func (s *SpheroDriver) readBody(length uint8) []uint8 {
return s.readNextChunk(int(length))
}
func (s *SpheroDriver) readNextChunk(length int) []uint8 {
read := make([]uint8, length)
bytesRead := 0
for bytesRead < length {
time.Sleep(1 * time.Millisecond)
n, err := s.adaptor().sp.Read(read[bytesRead:])
if err != nil {
return nil
}
bytesRead += n
}
return read
}