This commit is contained in:
FyloZ 2024-04-11 13:30:35 -04:00
parent 8b10e5ee6d
commit b22055a1ce
Signed by: william
GPG Key ID: 835378AE9AF4AE97
2 changed files with 53 additions and 75 deletions

View File

@ -19,6 +19,7 @@
#include <memory>
#define _USE_MATH_DEFINES
#include <cmath>
#include <random>
@ -26,14 +27,12 @@
using namespace nanogui;
namespace
{
namespace {
// Random number generator.
// Returns a random value such that _min <= val <= _max
//
template<typename _Scalar>
static inline _Scalar rand(_Scalar _min, _Scalar _max)
{
static inline _Scalar rand(_Scalar _min, _Scalar _max) {
static std::random_device rdev;
static std::default_random_engine re(rdev());
@ -49,8 +48,7 @@ namespace
}
IKApplication::IKApplication() : Screen(Vector2i(1280, 720), "GTI320 Labo sur la cinematique inverse"),
m_targetPos()
{
m_targetPos() {
m_armature = std::make_unique<gti320::Armature>();
m_ikSolver = std::make_unique<gti320::IKSolver>(m_armature.get(), m_targetPos);
@ -75,24 +73,20 @@ m_targetPos()
m_targetUI = std::make_unique<TargetUI>(tools, m_targetPos);
const int numLinks = m_armature->links.size();
for (int i = 0; i < numLinks; ++i)
{
for (int i = 0; i < numLinks; ++i) {
gti320::Link *link = m_armature->links[i];
if (!link->isEndEffector())
{
if (!link->isEndEffector()) {
m_linkUIArr.push_back(new LinkUI(m_armature->links[i], i, tools));
}
}
Button *solveButton = new Button(tools, "IK solve");
solveButton->set_callback([this]
{
solveButton->set_callback([this] {
ikSolve();
});
Button *resetButton = new Button(tools, "Reset");
resetButton->set_callback([this]
{
resetButton->set_callback([this] {
reset();
});
@ -100,8 +94,7 @@ m_targetPos()
reset();
}
bool IKApplication::keyboard_event(int key, int scancode, int action, int modifiers)
{
bool IKApplication::keyboard_event(int key, int scancode, int action, int modifiers) {
if (Screen::keyboard_event(key, scancode, action, modifiers))
return true;
if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS) {
@ -111,8 +104,7 @@ bool IKApplication::keyboard_event(int key, int scancode, int action, int modifi
return false;
}
void IKApplication::draw(NVGcontext* ctx)
{
void IKApplication::draw(NVGcontext *ctx) {
assert(m_armature->root != nullptr);
m_armature->updateKinematics();
@ -121,12 +113,10 @@ void IKApplication::draw(NVGcontext* ctx)
Screen::draw(ctx);
}
void IKApplication::reset()
{
void IKApplication::reset() {
// Reset all joints to zero angle
//
for (gti320::Link* l : m_armature->links)
{
for (gti320::Link *l: m_armature->links) {
l->eulerAng.setZero();
}
@ -136,23 +126,19 @@ void IKApplication::reset()
// Update UI
//
for (LinkUI* ui : m_linkUIArr)
{
for (LinkUI *ui: m_linkUIArr) {
ui->onArmatureChanged();
}
}
void IKApplication::ikSolve()
{
void IKApplication::ikSolve() {
m_ikSolver->solve();
for (LinkUI* ui : m_linkUIArr)
{
for (LinkUI *ui: m_linkUIArr) {
ui->onArmatureChanged();
}
}
void IKApplication::initializeArmature()
{
void IKApplication::initializeArmature() {
// Initialize the armature
//
gti320::Vector3f angs;
@ -182,8 +168,7 @@ void IKApplication::initializeArmature()
m_armature->root = link0;
}
void IKApplication::initializeTarget()
{
void IKApplication::initializeTarget() {
m_targetPos(0) = 1.0f;
m_targetPos(1) = 1.0f;
m_targetPos(2) = 0.0f;

View File

@ -1,6 +1,5 @@
#pragma once
#include <cfloat>
#include "IKSolver.h"
#include "Armature.h"
#include "SVD.h"
@ -31,16 +30,6 @@ float IKSolver::getError(Vector3f &dx) const {
return ddx.norm();
}
void jacobian(Jacobianf &m_J, Link *link, Vector3f &ri, int i) {
// axes x, y et z
for (int j = 0; j < 3; j++) {
// crossP
m_J(0, i) = link->M(j, 1) * ri(2) - link->M(j, 2) * ri(1);
m_J(1, i) = link->M(j, 0) * ri(2) - link->M(j, 2) * ri(0);
m_J(2, i) = link->M(j, 0) * ri(1) - link->M(j, 1) * ri(0);
}
}
template<typename _Scalar, int _Rows, int _Storage>
float dotP(SubMatrix<_Scalar, _Rows, Dynamic, _Storage> a, Vector<_Scalar, _Rows> b) {
_Scalar product = 0;
@ -63,43 +52,47 @@ void IKSolver::solve() {
// Each column corresponds to a separate link
for (int i = 0; i < numLinks; i++) {
Link *link = m_armature->links[i];
Vector3f shift = endEffector->globalPosition() - link->globalPosition();
Vector3f ri = endEffector->globalPosition() - link->globalPosition();
jacobian(m_J, link, shift, i);
for (int j = 0; j < 3; j++) {
auto ji = m_J.block(0, i * 3 + j, 3, 1);
auto oij = link->M.block(0, j, 3, 1);
ji(0, 0) = oij(1, 0) * ri(2) - oij(2, 0) * ri(1);
ji(1, 0) = oij(2, 0) * ri(0) - oij(0, 0) * ri(2);
ji(2, 0) = oij(0, 0) * ri(1) - oij(1, 0) * ri(0);
}
}
// TODO Compute the error between the current end effector
// Compute the error between the current end effector
// position and the target position by calling getError()
Vector3f dx;
float error = getError(dx);
// TODO Compute the change in the joint angles by solving:
// Compute the change in the joint angles by solving:
// df/dtheta * delta_theta = delta_x
// where df/dtheta is the Jacobian matrix.
auto svd = SVD(m_J);
svd.decompose();
// svd.getSigma() * svd.getV().transpose() * d_theta - svd.getU().transpose() * dx;
int m = svd.getSigma().size();
int rank = 0;
for (int i = 0; i < svd.getSigma().size(); i++) {
for (int i = 0; i < m; i++) {
if (svd.getSigma()(i) == 0) {
break;
}
rank++;
}
auto d_theta = Vector<float, Dynamic>(rank);
auto z = Vector<float, Dynamic>(rank);
auto z = Vector<float, Dynamic>(m);
for (int i = 0; i < rank; i++) {
auto ui = svd.getU().block(i, 0, 3, 1);
auto ui = svd.getU().block(0, i, 3, 1);
auto si = svd.getSigma()(i);
z(i) = dotP(ui, dx) / si;
}
Vector<float, Dynamic> d_theta = svd.getV() * z;
d_theta = svd.getV() * z;
// TODO Perform gradient descent method with line search
// Perform gradient descent method with line search
// to move the end effector toward the target position.
//
// Hint: use the Armature::unpack() and Armature::pack() functions
@ -115,5 +108,5 @@ void IKSolver::solve() {
m_armature->updateKinematics();
alpha /= 2;
} while (getError(dx) < error);
} while (getError(dx) >= error);
}