Here’s a little project that my 6 year old son and I have been working on using some ServoCity’s Actobotics parts. Once we have some code written, we’ll do a codeshare and a bill of materials used.
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Looks like a cool project and I really like that frame! 
That is some impressive framework. I’m guessing your 6 year old will be able to ride it.
I am going to show this to the students we are working with, can’t wait to show them a demo video.
@ kirklynk - Awesome project! Could you provide a list of Actobotics parts that are being used?
@ munderhill - I will as soon as I have everything bolted in place… I currently have a bill of material of all the parts that I have purchased but not all of them are being used on this project.
@ Gary - Feel free to and as soon as I have something coded, I will make some videos of it when it is operational.
Fantastic, I can’t wait.
Here is a list of all the ServoCity parts used on this project:
2 - 9.00" Aluminum Channel (585450)
16 - Aluminum Beams (585412)
8 - 90° Quad Hub Mount A (545420)
4 - Standard Hitec ServoBlocks
2 - Hub Spacers (545384)
8 - Hub Spacers (545376)
4 - 90° Hub to Hub Mount (545400)
2 - Aluminum Robot Shocks (585032)(pairs)
2 - 17mm Hex Wheel Adaptors
4 - 0.770" Set Screw Hubs (545576)
4 - Aluminum Clamping Motor Mount
16+ - 6-32 Aluminum Standoffs (Round) (534-3489)
1 - Battery Mount A (585564)
4 - 90° Dual Side Mount (585470)(pairs)
100+ - Locking Washers (91102A007)
6+ - #6 Standard Washers Pack (632144)
2+ - 6-32 Socket Head Machine Screw (Zinc-Plated)( 632106)
2+ - 6-32 Socket Head Machine Screw (Zinc-Plated)( 632110)
4+ - 6-32 Socket Head Machine Screw (Zinc-Plated)( 632114)
2 - 1.50" Aluminum Channel (585440)
4 - 45° Dual Angle Channel Bracket (585426)
2 - Channel Connector Plate A (545532)(2 pack)
2 - Beam Attachment Blocks (585403)(4 pack)
I’ll update as more parts are added
Warning to self - Ensure that you know what you are building first, as you can become overwhelmed with purchasing parts some of which you may never use even though the intent is good.
@ kirklynk - Thanks!
Ain’t that the truth!
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I have that exact problem myself!
Oh! Shiny!
I’ll have two of those. 
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"Yeah, I could probably use that. I should have one. Maybe two."
Corollary : "Don’t throw that away - it has a perfectly good switch on it"
The first step is admitting you have a problem. And man, do I have a problem.
I’ll take a bet that at least 99.99% of the people on this forum suffer from this very thing. I know I do.
I am due to make a house move overseas soon and the thought of clearing out some of my stuff is scary. My wife already told me I should only take what I need. I told her I need it all 
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And some more, but just a few bits more, not much really… :whistle:
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Over the past few weeks we have done some changes to the Rover and we finally received a LidarLite sensor yesterday to integrate into it. So where does this project stand? So far in terms of electronics, here’s what we have
[ol]FezCerb40 II
4x Servos
4x HobbyWing QuicRun 860 dual motor esc
2x IR sensors - Sharp GP2Y0A41SK0F Analog Distance Sensor 4-30cm
LidarLite sensor
1x ONYX 5000mah LIPO battery
[/ol]
We have made a few modifications to the frame as show in these pictures. It is hard to give you a design for the frame as it was design on the go from our heads and not from any plans.
Here is our preliminary code (I will expand as time permits):
using System;
using Microsoft.SPOT;
using Microsoft.SPOT.Hardware;
using GHI.Pins;
using System.Threading;
using System.Diagnostics;
namespace Rover
{
public enum RunModeOption { Forward, Reverse, Brake }
public class Program
{
const double SYSTEM_VOLTAGE = 3.3;
const double TYPICAL_SERVO_DURATION_RANGE = 1200; //This is based on a typical servo range
const uint ESC_NEUTRAL_POSITION = 1500;
const double IR_THRESHOLD_CUT_OFF_VOLTAGE = 1.20; //Roughly 10cm from object
readonly AnalogInput _frontMountedIRSensor;
readonly AnalogInput _rearMountedIRSensor;
readonly PWM _electronicSpeedControllerA;
readonly PWM _electronicSpeedControllerB;
private RunModeOption _lastRunModeOption;
private bool _isReady;
uint _current;
uint _targetPWMDuration;
private InputPort _escBECReadyMode;
private I2CDevice _lidarSensor;
public Program()
{
_current = ESC_NEUTRAL_POSITION;
_targetPWMDuration = 2100;
_lidarSensor = new I2CDevice(new I2CDevice.Configuration(0x62, 100)); //0x62 is the I2C address of the LIDARLite sensor
_isReady = false;
_lastRunModeOption = RunModeOption.Brake;
_frontMountedIRSensor = new AnalogInput(FEZCerb40II.AnalogInput.PC0);
_rearMountedIRSensor = new AnalogInput(FEZCerb40II.AnalogInput.PC1);
_escBECReadyMode = new InputPort(FEZCerb40II.Gpio.PC9, false, Port.ResistorMode.PullDown);
_electronicSpeedControllerA = new PWM(FEZCerb40II.PwmOutput.PC7, 20000, 1500, PWM.ScaleFactor.Microseconds, false);
_electronicSpeedControllerB = new PWM(FEZCerb40II.PwmOutput.PC6, 20000, 1500, PWM.ScaleFactor.Microseconds, false);
}
public static void Main()
{
Program p = new Program();
p.Run();
Thread.Sleep(Timeout.Infinite);
}
private void Run()
{
//Start PWM outputs
PWM.Start(new PWM[] { _electronicSpeedControllerA, _electronicSpeedControllerB });
//Fire up some child threads
new Thread(CalculateDistanceAndSetDesireSpeedOfRover).Start();
new Thread(SetControllerSpeed).Start();
new Thread(ContinuouslyReadLidarSensor).Start();
_isReady = true;
}
private void ContinuouslyReadLidarSensor()
{
while(true) {
}
}
private void SetControllerSpeed()
{
bool isReversing = false;
RunModeOption lastRunMode = RunModeOption.Brake;
while(true)
{
var escOnState = _escBECReadyMode.Read();
if(_isReady && escOnState)
{
switch(_lastRunModeOption)
{
case RunModeOption.Forward:
if(lastRunMode == RunModeOption.Reverse && isReversing)
{
isReversing = false;
ApplyBrakes();
}
//Gradually increases the speed
if(_current < _targetPWMDuration)
_current += 50;
//Gradually decreases the speed
if(_current > _targetPWMDuration)
_current -= 50;
break;
case RunModeOption.Reverse:
if(lastRunMode == RunModeOption.Forward && !isReversing)
{
isReversing = true;
ApplyBrakes();
}
if(_current > (uint)(ESC_NEUTRAL_POSITION - (TYPICAL_SERVO_DURATION_RANGE / 2)))
_current -= 50;
break;
case RunModeOption.Brake:
default:
ApplyBrakes();
break;
}
}
else
{
ApplyBrakes();
}
_electronicSpeedControllerA.Duration = _electronicSpeedControllerB.Duration = _current;
lastRunMode = _lastRunModeOption;
Thread.Sleep(10);
}
}
private void ApplyBrakes()
{
_current = _electronicSpeedControllerA.Duration = _electronicSpeedControllerB.Duration = ESC_NEUTRAL_POSITION;
if(Debugger.IsAttached)
{
Debug.Print("Applying the brakes");
}
Thread.Sleep(2000);
}
private void CalculateDistanceAndSetDesireSpeedOfRover()
{
while(true)
{
if(!_isReady)
continue;
var frontIRSensor = System.Math.Round(_frontMountedIRSensor.Read() * 100 * SYSTEM_VOLTAGE) / 100;
var rearIRSensor = System.Math.Round(_rearMountedIRSensor.Read() * 100 * SYSTEM_VOLTAGE) / 100;
if((frontIRSensor >= IR_THRESHOLD_CUT_OFF_VOLTAGE && _lastRunModeOption == RunModeOption.Forward) ||
(rearIRSensor >= IR_THRESHOLD_CUT_OFF_VOLTAGE && frontIRSensor >= IR_THRESHOLD_CUT_OFF_VOLTAGE) ||
(rearIRSensor >= IR_THRESHOLD_CUT_OFF_VOLTAGE && _lastRunModeOption == RunModeOption.Reverse))
{
_lastRunModeOption = RunModeOption.Brake;
CalculateAlternateRoute();
}
else if(frontIRSensor >= IR_THRESHOLD_CUT_OFF_VOLTAGE && rearIRSensor < IR_THRESHOLD_CUT_OFF_VOLTAGE)
{
_lastRunModeOption = RunModeOption.Reverse;
}
else
{
//Calculate route before moving forward
if(_lastRunModeOption == RunModeOption.Reverse)
CalculateAlternateRoute();
_lastRunModeOption = RunModeOption.Forward;
if(frontIRSensor > 0.40)
_targetPWMDuration = (uint)(ESC_NEUTRAL_POSITION + (TYPICAL_SERVO_DURATION_RANGE / 8)); //Move forward at 50%
else
_targetPWMDuration = (uint)(ESC_NEUTRAL_POSITION + (TYPICAL_SERVO_DURATION_RANGE / 2)); //Move forward at 100%
}
Thread.Sleep(10);
}
}
private void CalculateAlternateRoute()
{
Debug.Print("Calculating Alternate Route");
//TODO: Lidar sensor
}
}
}
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@ kirklynk - Looking good! I’m looking forward to some video!
I saw it a few ago at a local event, it’s pretty cool.