Documentation
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Overview ¶
Package tpspace defines an assortment of precomputable trajectories which can be used to plan nonholonomic 2d motion
Index ¶
Constants ¶
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Variables ¶
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Functions ¶
This section is empty.
Types ¶
type PTG ¶
type PTG interface {
// CToTP Converts an (x, y) cartesian coord to a (k, d) TP-space coord
// d is the distance along a trajectory, k is a discretized uint index corresponding to an alpha value in [-pi, pi]
// See `index2alpha` for more
// Also returns a bool representing whether the xy is a within-traj match vs an extrapolation
CToTP(x, y float64) []*TrajNode
// RefDistance returns the maximum distance that a single precomputed trajectory may travel
RefDistance() float64
// Returns the set of trajectory nodes for alpha index K
Trajectory(uint) []*TrajNode
}
PTG is a Parameterized Trajectory Generator, which defines how to map back and forth from cartesian space to TP-space PTG coordinates are specified in polar coordinates (alpha, d) One of these is needed for each sort of motion that can be done.
func NewPTGGridSim ¶
func NewPTGGridSim(simPTG PrecomputePTG, arcs uint, simDist float64) (PTG, error)
NewPTGGridSim creates a new PTG by simulating a PrecomputePTG for some distance, then cacheing the results in a grid for fast lookup.
type PTGProvider ¶
type PTGProvider interface {
// PTGs returns the list of PTGs associated with this provider
PTGs() []PTG
}
PTGProvider is something able to provide a set of PTGs associsated with it. For example, a frame which precomputes a number of PTGs.
type PrecomputePTG ¶
type PrecomputePTG interface {
// PTGVelocities returns the linear and angular velocity at a specific point along a trajectory
PTGVelocities(alpha, t, x, y, phi float64) (float64, float64, error)
}
PrecomputePTG is a precomputable PTG.
func NewAlphaPTG ¶
func NewAlphaPTG(maxMMPS, maxRPS, k float64) PrecomputePTG
NewAlphaPTG creates a new PrecomputePTG of type simPtgAlpha. K is unused for alpha PTGs *for now* but we may add in the future.
func NewCCPTG ¶
func NewCCPTG(maxMMPS, maxRPS, k float64) PrecomputePTG
NewCCPTG creates a new PrecomputePTG of type ptgDiffDriveCC.
func NewCCSPTG ¶
func NewCCSPTG(maxMMPS, maxRPS, k float64) PrecomputePTG
NewCCSPTG creates a new PrecomputePTG of type ptgDiffDriveCCS.
func NewCSPTG ¶
func NewCSPTG(maxMMPS, maxRPS, k float64) PrecomputePTG
NewCSPTG creates a new PrecomputePTG of type ptgDiffDriveCS.
func NewCirclePTG ¶
func NewCirclePTG(maxMMPS, maxRPS, k float64) PrecomputePTG
NewCirclePTG creates a new PrecomputePTG of type ptgDiffDriveC.
type TrajNode ¶
type TrajNode struct {
// TODO: cache pose point and orientation so that we don't recompute every time we need it
Pose spatialmath.Pose // for 2d, we only use x, y, and OV theta
Time float64 // elapsed time on trajectory
Dist float64 // distance travelled down trajectory
K uint // alpha k-value at this node
LinVelMMPS float64 // linvel in millimeters per second at this node
AngVelRPS float64 // angvel in radians per second at this node
// contains filtered or unexported fields
}
TrajNode is a snapshot of a single point in time along a PTG trajectory, including the distance along that trajectory, the elapsed time along the trajectory, and the linear and angular velocity at that point.
Source Files