robocar-steering/pkg/steering/corrector.go

263 lines
7.8 KiB
Go

package steering
import (
"encoding/json"
"fmt"
"github.com/cyrilix/robocar-protobuf/go/events"
"go.uber.org/zap"
"os"
)
type Corrector interface {
AdjustFromObjectPosition(currentSteering float64, objects []*events.Object) float64
}
type OptionCorrector func(c *GridCorrector)
func WithGridMap(configPath string) OptionCorrector {
var gm *GridMap
if configPath == "" {
zap.S().Warnf("no configuration defined for grid map, use default")
gm = &defaultGridMap
} else {
var err error
gm, err = loadConfig(configPath)
if err != nil {
zap.S().Panicf("unable to load grid-map config from file '%v': %w", configPath, err)
}
}
return func(c *GridCorrector) {
c.gridMap = gm
}
}
func WithObjectMoveFactors(configPath string) OptionCorrector {
var omf *GridMap
if configPath == "" {
zap.S().Warnf("no configuration defined for objects move factors, use default")
omf = &defaultObjectFactors
} else {
var err error
omf, err = loadConfig(configPath)
if err != nil {
zap.S().Panicf("unable to load objects move factors config from file '%v': %w", configPath, err)
}
}
return func(c *GridCorrector) {
c.objectMoveFactors = omf
}
}
func loadConfig(configPath string) (*GridMap, error) {
content, err := os.ReadFile(configPath)
if err != nil {
return nil, fmt.Errorf("unable to load grid-map config from file '%v': %w", configPath, err)
}
var gm GridMap
err = json.Unmarshal(content, &gm)
if err != nil {
return nil, fmt.Errorf("unable to unmarshal json config '%s': %w", configPath, err)
}
return &gm, nil
}
func WithImageSize(width, height int) OptionCorrector {
return func(c *GridCorrector) {
c.imgWidth = width
c.imgHeight = height
}
}
func WidthDeltaMiddle(d float64) OptionCorrector {
return func(c *GridCorrector) {
c.deltaMiddle = d
}
}
func NewGridCorrector(options ...OptionCorrector) *GridCorrector {
c := &GridCorrector{
gridMap: &defaultGridMap,
objectMoveFactors: &defaultObjectFactors,
deltaMiddle: 0.1,
imgWidth: 160,
imgHeight: 120,
}
for _, o := range options {
o(c)
}
return c
}
type GridCorrector struct {
gridMap *GridMap
objectMoveFactors *GridMap
deltaMiddle float64
imgWidth, imgHeight int
}
/*
AdjustFromObjectPosition modify steering value according object positions
1. To compute steering correction, split in image in zones and define correction value for each zone
Steering computed
: -1 -0.66 -0.33 0 0.33 0.66 1
0% |-----|-----|-----|-----|-----|-----|
: | 0 | 0 | 0 | 0 | 0 | 0 |
20% |-----|-----|-----|-----|-----|-----|
: | 0 | 0 | 0 | 0 | 0 | 0 |
40% |-----|-----|-----|-----|-----|-----|
: | 0 | 0 | 0.25|-0.25| 0 | 0 |
60% |-----|-----|-----|-----|-----|-----|
: | 0 | 0.25| 0.5 |-0.5 |-0.25| 0 |
80% |-----|-----|-----|-----|-----|-----|
: | 0.25| 0.5 | 1 | -1 |-0.5 |-0.25|
100%|-----|-----|-----|-----|-----|-----|
2. For straight (current steering near of 0), search nearest object and if:
* left and right values < 0: use correction from right value according image splitting
* left and right values > 0: use correction from left value according image splitting
* left < 0 and right values > 0: use (right + (right - left) / 2) value
3. If current steering != 0 (turn on left or right), shift right and left values proportionnaly to current steering and
apply 2.
: -1 -0.66 -0.33 0 0.33 0.66 1
0% |-----|-----|-----|-----|-----|-----|
: | 0 | 0 | 0 | 0 | 0 | 0 |
20% |-----|-----|-----|-----|-----|-----|
: | 0.2 | 0.1 | 0 | 0 |-0.1 |-0.2 |
40% |-----|-----|-----|-----|-----|-----|
: | ... | ... | ... | ... | ... | ... |
*/
func (c *GridCorrector) AdjustFromObjectPosition(currentSteering float64, objects []*events.Object) float64 {
if len(objects) == 0 {
return currentSteering
}
grpObjs := GroupObjects(objects, c.imgWidth, c.imgHeight)
// get nearest object
nearest, err := c.nearObject(grpObjs)
if err != nil {
zap.S().Warnf("unexpected error on nearest search object, ignore objects: %v", err)
return currentSteering
}
if currentSteering > -1*c.deltaMiddle && currentSteering < c.deltaMiddle {
// Straight
return currentSteering + c.computeDeviation(nearest)
} else {
// Turn to right or left, so search to avoid collision with objects on the right
// Apply factor to object to move it at middle. This factor is function of distance
factor, err := c.objectMoveFactors.ValueOf(float64(nearest.Right), float64(nearest.Bottom))
if err != nil {
zap.S().Warnf("unable to compute factor to apply to object: %v", err)
return currentSteering
}
objMoved := events.Object{
Type: nearest.Type,
Left: nearest.Left + float32(currentSteering*factor),
Top: nearest.Top,
Right: nearest.Right + float32(currentSteering*factor),
Bottom: nearest.Bottom,
Confidence: nearest.Confidence,
}
result := currentSteering + c.computeDeviation(&objMoved)
if result < -1. {
result = -1.
}
if result > 1. {
result = 1.
}
return result
}
}
func (c *GridCorrector) computeDeviation(nearest *events.Object) float64 {
var delta float64
var err error
zap.S().Debugf("search delta value for bottom limit: %v", nearest.Bottom)
if nearest.Left < 0 && nearest.Right < 0 {
delta, err = c.gridMap.ValueOf(float64(nearest.Right)*2-1., float64(nearest.Bottom))
}
if nearest.Left > 0 && nearest.Right > 0 {
delta, err = c.gridMap.ValueOf(float64(nearest.Left)*2-1., float64(nearest.Bottom))
} else {
delta, err = c.gridMap.ValueOf(float64(float64(nearest.Left)+(float64(nearest.Right)-float64(nearest.Left))/2.)*2.-1., float64(nearest.Bottom))
}
if err != nil {
zap.S().Warnf("unable to compute delta to apply to steering, skip correction: %v", err)
delta = 0
}
zap.S().Debugf("new deviation computed: %v", delta)
return delta
}
func (c *GridCorrector) nearObject(objects []*events.Object) (*events.Object, error) {
if len(objects) == 0 {
return nil, fmt.Errorf("list objects must contain at least one object")
}
if len(objects) == 1 {
return objects[0], nil
}
var result *events.Object
for _, obj := range objects {
if result == nil || obj.Bottom > result.Bottom {
result = obj
continue
}
}
return result, nil
}
func NewGridMapFromJson(fileName string) (*GridMap, error) {
content, err := os.ReadFile(fileName)
if err != nil {
return nil, fmt.Errorf("unable to read content from %s file: %w", fileName, err)
}
var ft GridMap
err = json.Unmarshal(content, &ft)
if err != nil {
return nil, fmt.Errorf("unable to unmarshal json content from %s file: %w", fileName, err)
}
// TODO: check structure is valid
return &ft, nil
}
type GridMap struct {
DistanceSteps []float64 `json:"distance_steps"`
SteeringSteps []float64 `json:"steering_steps"`
Data [][]float64 `json:"data"`
}
func (f *GridMap) ValueOf(steering float64, distance float64) (float64, error) {
if steering < f.SteeringSteps[0] || steering > f.SteeringSteps[len(f.SteeringSteps)-1] {
return 0., fmt.Errorf("invalid steering value: %v, must be between %v and %v", steering, f.SteeringSteps[0], f.SteeringSteps[len(f.SteeringSteps)-1])
}
if distance < f.DistanceSteps[0] || distance > f.DistanceSteps[len(f.DistanceSteps)-1] {
return 0., fmt.Errorf("invalid distance value: %v, must be between %v and %v", steering, f.DistanceSteps[0], f.DistanceSteps[len(f.DistanceSteps)-1])
}
// search column index
var idxCol int
// Start loop at 1 because first column should be skipped
for i := 1; i < len(f.SteeringSteps); i++ {
if steering < f.SteeringSteps[i] {
idxCol = i - 1
break
}
}
var idxRow int
// Start loop at 1 because first column should be skipped
for i := 1; i < len(f.DistanceSteps); i++ {
if distance < f.DistanceSteps[i] {
idxRow = i - 1
break
}
}
return f.Data[idxRow][idxCol], nil
}