Monday, January 24, 2022

2022 Day 15 and 16: Full Climb Video

 Climber Testing

We added a crossbar between the hooks and moved our string to pull from around the lower arm pivot shaft and pull on the crossbar. This allows us to pull down closer to a straight line from the hooks to the spool. We also added some pool noodles so that if (when) this chassis falls off the bar it won't be damaged as badly.

After some more testing, we were able to get a successful climb sequence. 
This version of the prototype doesn't currently work when we added weight (35lb plate) because it's powered with a timing belt, the competition one will likely be chain or gear driven. This climb also takes the robot to a full latch on the traversal bar which in our current design this likely brings part of our bumper above the high bar (a G108 violation) so we will only pull off the high bar and hang from the top hooks in a real match.

Launcher Prototype

Our launcher prototype is coming along and we should have some test video coming soon. The current plan is a flywheel with a top roller, adjustable hood, and turret. If we need to reduce features they will probably keep that priority order, the turret is nice to have but not necessary, the hood could be simplified to 2 positions instead of continuous, and the top roller should allow us to launch balls into the goals with less energy in the ball when they enter to reduce bounce-outs.

- Spectrum

Sunday, January 23, 2022

2022 Day 14 & 15: More Climber Testing

 Climber Testing

We constructed more of a "climber chassis" over the past few days to be able to simulate the climber with both arms.

The first test of the climber chassis did work well. We didn't do a full continuous climb but if you want to watch multiple videos they are all in this gallery. The video below is the prototype moving from the high bar to the traversal mostly by itself.

This prototype is still only powered by a single motor and we will be adding bars across the arms to help synchronize their motion. We will also be adding weight to the chassis to see how it changes the climber's behavior.

Friday, January 21, 2022

2022 Day 12 & 13: Swerve Assembly and Controls Priorities

Swerve Assembly

We began the assembly of our Swerve Drive Specialities MK4i modules that we are planning to use this season. We used the MK3 modules this summer at the Texas Cup and believe the MK4i will fit our design better this year along with having the 1.5" wide wheels.

Controls Priorities

Our controls team met to go over our priorities for the season and to split up into areas of focus.

Climber Testing

The test climber had another accident, it also had some successes but the accident are more interesting as we learn what needs to be improved.
- Spectrum

Wednesday, January 19, 2022

2022 Day 10 & 11: Weekly Recap

Tuesday's our weekly Design Recap.

Photon 8515 will be building a modified Everybot this year and we will try to publish the changes and additions we make to the design.

- Spectrum

Monday, January 17, 2022

2022 Day 9: Bootcamp Build Day & a successful climber prototype

 Bootcamp Build Day

We started the day with our 1st Bootcamp Build Day of the year we had students and teachers representing 5 young Houston area teams on site for a few hours to answer their questions, give design advice, and help with the FRC control system. Members of Pearadox FRC5414 were here to help as part of our partnership in the Houston FRC Development Program this year. Our next session is in two weeks and we will be helping teams finish up their drive bases, electronics, and making progress on their robots. 

Climber Test

We were able to rebuild the climber prototype after last night's crash and improve it in the process. Below is a video of it successfully pulling from one bar to the other. With a little help to limit the swinging this time. In the next version, we will add springs to extend the upper arm and a pneumatic cylinder to extend the lower arm.

The theory behind the climb

Here is the basic idea of how we currently plan to implement the climb.

- Spectrum

Sunday, January 16, 2022

2022 Day 7 & 8: Intake Testing and a New Climber Concept

Intake Testing

We started on a more complete intake test rig with bumpers and more adjustability.

We are using silicone bands in this video, soft silicone has worked well in our past intakes (2019) and it appears to grip the balls well this year.

Simple Tests

A lot of our "prototypes" don't need to be complicated to prove concepts. In this quick clip we used part of a prototype from 2020 to see how the balls would behave if we used a timing belt as part of  a ball tower.

Climber Concepts

 We began working on a new climber concept that uses a double-jointed arm that extends with springs and climbs with a winch. The geometry of this climb appears to work better than some of the others we were working on.

We spent time today mocking it up with laser-cut parts and 3D printed connectors. The 2 extra CIMs are just for ballast to simulate the center of mass of the actual robot.

We were able to complete the construction of our practice hangar and run the prototype on it. One of the first attempts with the prototype went one of the more predictable ways.

We will rebuild it this weekend with lessons learned (more perimeters in the prints, more gussets, and bolts/rivets into the tubing) and hopefully future attempts will be more successful. Failures like these are to be expected while prototyping, this is why we often use scrap material or cheap and quick-to-make parts like the 3D printed tube connectors and shaft collars. Failing quickly is one of the best ways to get a robust system in your final robot.'

- Spectrum

Friday, January 14, 2022

2022 Day 6: Climber Model

 We made a 1/5th scale model of one of our climber ideas. This one has several issues, and some of them are caused by it being scaled-down, and some of them are likely inherent in the design.

We made several interactions, printed, and laser cut some parts, so the joints acted more like we wanted; we also added nuts to simulate the robot's center of gravity. These helped but didn't fully solve the problems.

More videos and photos can be found in our photo gallery:

From playing with this model and doing more CAD sketches, we will likely add another degree of freedom to the system, most likely a motor (possibly pneumatic) to extend and retract the hook on the arm. This should allow the climb to behave correctly across various center of gravity positions and enable us to quickly climb to the mid-bar without fully completing the first curl of the whole climb sequence. We also still discussing if we will use chain/sprockets or a Dyneema cord winch to power the arm joint. 

Here is a sketch of the new configuration; this has a 6 in extension and appears to work with a center of mass 6.5" to 15" and roughly centered in the robot. Not shown, but if we needed this climb should be able to curl onto the low bar for 4 pts. 

- Spectrum