diff --git a/frc971/zeroing/zeroing.cc b/frc971/zeroing/zeroing.cc
new file mode 100644
index 0000000..a0d3ba4
--- /dev/null
+++ b/frc971/zeroing/zeroing.cc
@@ -0,0 +1,50 @@
+#include "frc971/zeroing/zeroing.h"
+#include <math.h>
+#include <vector>
+
+namespace frc971 {
+namespace zeroing {
+
+ZeroingEstimator::ZeroingEstimator(double index_difference,
+                                   size_t max_sample_count) {
+  index_diff_ = index_difference;
+  samples_idx_ = 0;
+  max_sample_count_ = max_sample_count;
+  start_pos_samples_.reserve(max_sample_count);
+}
+
+void ZeroingEstimator::UpdateEstimate(const ZeroingInfo & info) {
+  if (start_pos_samples_.size() < max_sample_count_) {
+    start_pos_samples_.push_back(info.pot - info.encoder);
+  } else {
+    start_pos_samples_[samples_idx_] = info.pot - info.encoder;
+  }
+  samples_idx_ = (samples_idx_ + 1) % max_sample_count_;
+
+  double start_average = 0.0;
+  for (size_t i = 0; i < start_pos_samples_.size(); ++i) {
+    start_average += start_pos_samples_[i];
+  }
+
+  // Calculates the average of the starting position.
+  start_average = start_average / start_pos_samples_.size();
+  /* If the index_encoder is invalid, then we use
+   * the average of the starting position to
+   * calculate the position.
+   */
+  if (info.index_count == 0) {
+    pos_ = start_average + info.encoder;
+  } else {
+  	// We calculate an aproximation of the value of the last index position.
+    double index_pos = start_average + info.index_encoder;
+	// We round index_pos to the closest valid value of the index.
+    double accurate_index_pos = (round(index_pos / index_diff_)) * index_diff_;
+	// We use accurate_index_pos to calculate the position.
+    pos_ = accurate_index_pos + info.encoder - info.index_encoder;
+  }
+}
+
+double ZeroingEstimator::getPosition() { return pos_; }
+
+}  // namespace zeroing
+}  // namespace frc971