Search found 8 matches

by john
Sat Aug 19, 2017 3:48 pm
Forum: EV3 Software
Topic: ExceptionInInitializerError after declaring more than one motor
Replies: 2
Views: 338

ExceptionInInitializerError after declaring more than one motor

Hi All, I have bee getting an ExceptionInInitializerError which was Caused by: lejos.hardware.DeviceException: unable to open port, when declaring more than one motor... I have pinpointed this error to be coming from the following lines of code: EncoderMotor cam_motor = new UnregulatedMotor(MotorPor...
by john
Wed Sep 09, 2015 9:15 pm
Forum: EV3 Software
Topic: 'Motor stops' between pilot.setTravelSpeed() calls
Replies: 7
Views: 2060

Re: 'Motor stops' between pilot.setTravelSpeed() calls

If I use regulated motors, I must use the synchonizeWith() and startSynchronization() methods when setting the translational velocity of the differential drive? Else the velocity of the motors will not be changed at the same time instant and hence will cause the robot to steer instead of driving in ...
by john
Wed Aug 12, 2015 2:57 pm
Forum: EV3 Software
Topic: 'Motor stops' between pilot.setTravelSpeed() calls
Replies: 7
Views: 2060

Re: 'Motor stops' between pilot.setTravelSpeed() calls

I see, so the only option I have at the moment is to create 2 instances of Ev3LargeMotor, and use the setPower() method calls ? I will then need to estimate the pose from odometry manually from the motor encoders, and not use poseProvider?
by john
Wed Aug 12, 2015 2:05 pm
Forum: EV3 Software
Topic: 'Motor stops' between pilot.setTravelSpeed() calls
Replies: 7
Views: 2060

Re: 'Motor stops' between pilot.setTravelSpeed() calls

Many thanks for your post. From where can I download the classes please and how can I integrate them in my project? as I am new to leJOS and github, and I need to have continuous motion in leJOS for a university project. If I use the chassis classes, will I still be able to use the poseprovider to o...
by john
Tue Aug 11, 2015 4:19 pm
Forum: EV3 Software
Topic: 'Motor stops' between pilot.setTravelSpeed() calls
Replies: 7
Views: 2060

'Motor stops' between pilot.setTravelSpeed() calls

Hi, I am using a point to point navigation controller which I programmed myself, to compute the required translational and angular/steer velocities for a differential drive robot. I am using the setTravelSpeed and steer methods provided by the differentialpilot, however between one method call (or 1...
by john
Tue Aug 11, 2015 3:45 pm
Forum: NXJ Software
Topic: leJOS on the Raspberry Pi - including USB and Bluetooth communication
Replies: 3
Views: 2071

Re: leJOS on the Raspberry Pi - including USB and Bluetooth communication

I have attempted to use sockets, programming the EV3 as a server. The raspberry pi can successfully communicate with the EV3 using wifi or USB (connected to the 'PC' labeled port, so the EV3 can still communicate through wifi with other devices ).
by john
Fri Jun 26, 2015 5:14 pm
Forum: NXJ Software
Topic: leJOS on the Raspberry Pi - including USB and Bluetooth communication
Replies: 3
Views: 2071

Re: leJOS on the Raspberry Pi - including USB and Bluetooth communication

Many thanks for your tutorial I have just managed to connect an NXT to the Raspberry Pi. Will this also work when connecting an EV3 brick to the Pi ?

Thanks & Regards,

John
by john
Wed Jun 10, 2015 8:23 pm
Forum: NXJ Software
Topic: Cannot Send Data from NXT2Wifi
Replies: 1
Views: 830

Cannot Send Data from NXT2Wifi

Dear All, I need to use the NXT and Wi Fi Communications for my project. I am using the NXT2Wifi sensor, and I am able to send and receive data on the device using serial rs232 commands. However when using Lejos/Java I can only receive data on the NXT2Wifi and I am not able to send info, even though...

Go to advanced search