Difference between revisions of "Geared Aerodynamic Pan and Tilt"

Revision as of 19:30, 27 February 2018

February 2018

Introduction

Having designed and released a pile of different Pan and Tilt units I decided to try and make some improvements. I came up with a list of simple design goals that were based on requests and experiences with my and other PnT's. The list then, in order of importance is:

• Lighter and Faster than my HD Pan and tilt (100g)

- New weight is 80g with the selected components

• Is smooth and precise with excellent centering

- With a new programmable digital Hitec HS-5245MG servo, it is extremely smooth and centers beautifully

• Is more aerodynamic

- Now with both servos mounted below the deck, it is very aerodynamic

• Can be made from off-the-shelf components

- All but one component is made from standard off-the-shelf parts (see text)

• Rotates 360 degrees or more

- Rotation can be programmed from 236° to 398°

• Tilts down 50 degrees or more

- Tilts down 42° (see text)

NOTE Apologies to all followers in Europe and Australia! The components selected started with a new (awesome) drive gear from ServoCity.com which I know can be very hard to find outside the US. The drive gear comes with the Hitec spline already molded in which made the design and subsequent build much easier. Of course this also means the gear shaft and bearings are imperial dimensions.

The new unit has a lower profile and needs a smaller through-deck hole:

Base unit showing Coupler and Bearing plate

Tilt Configurations

For this project I decided to keep it simple so there is only one tilt set-up and one pan only set-up.

Notes on Standard Configuration

• TBA

Parts and Specifications

Parts

Print Parts

• Base Plate
• Bearing Support Plate
• Tilt Servo Mount Bracket
• Tilt Turret
• Tilt Deck
• Tilt Deck Slide Covers
• Pan Deck

Off the Shelf Parts

Hardware

• 4x M2.5x6mm Machine screws
• 4x M2.5 Flat Washers
• 8x M3 x 6mm Machine Screws
• 3x M3 x 10mm Aluminum Stand-off
• 1x M3 x 30mm Machine Screw
• 1x M3 Nylok Nut
• 2x M2 x 8mm Machine Screw
• 2X M2 Hex Nut
• 2x M2 x 4mm Machine Screw
• 6x M2 x 5mm Flat Head Machine Screw
• 1x M2 Flat Washer

Servos

Pan - GWS S125-1T (25 tooth)

NOTE: The GWS S125-1t servo can be found with both a 23 tooth and 25 tooth spline. The 23 tooth spline was discontinued by GWS in 2014 but there is still lots of inventory out there. The 25 tooth which is identical to Futaba, must be found for this project.

Tilt - 9g/120 Degree servo

NOTE: This project was designed using a Corona DS929MG servo. While this servo works very well it is heavy at 14.1g. Most "9g" size servos should fit with small adjustments.

Hardware

1x  Actobotics #525142 25t Futaba Servo Extension (Coupler)

NOTE: For those not in the US, the US supplier has given me the website which identifies their sellers outside the US:

https://www.servocity.com/international

One such seller, StepLab, has commented on my Thingiverse page they have the parts for this project.

Alternatively, you can also print a coupler which fastens to a servo wheel. This part, Futaba_Servo_Coupler_v2.stl, can be found below and is now included in the download. It is not nearly as strong as the aluminum piece and must be very accurately printed to work.

1x  0.375"ID x 0.625"OD x 0.156"L Ball Bearing w/dual shield

1x  3" x 0.047" Steel Wire

1x   25mm x 45mm x 4mm Align PU-Gel Pad

Fasteners

2x  M3 x 20mm Nylon PHS

4x  M3 x 8mm SHCS

6x  M3 Flat Washer

4x  M2.5 x 8mm SHCS

4x  M2.5 Flat Washer

4x  M2 x 6mm SHCS

4x  M2 Flat Washer

4x  M3 x 15mm Aluminum Stand-offs

Mechanical Specifications

Total weight with all hardware and a true 9g tilt servo - 93 grams

Total weight without servos - 32 grams

Pan rotaion - 385 degrees

Tilt range, Std Camera Mounts - 0-70 degrees (down)

Tilt range, Over-Under Mounts - -19 (up) to 45 degrees (down)

Parts Preparation

On any 3D print project, part preparation is key to a successful completion. The following images show what work needs to be done for this success.

Servo Plate/Lower Deck Mount

The servo mount needs 4 holes tapped to M3 and 4 holes tapped to M2.5:

Bearing Plate/Upper Deck Mount

The assumption is your printer (or service) will hold the tolerance designed on an inside diameter. If your printer adds too much material you will need to make adjustments to accommodate the bearing OD which should push in with a little resistance:

Turret Base

The Turret needs 2 holes tapped to M3 and 2 holes tapped to M2:

Like the bearing plate, the assumption is your printer (or service) will hold the tolerance designed on an inside diameter. If your printer adds too much material you will need to make adjustments to accommodate the coupler OD (0.375") which should push in with a little resistance:

Servo Coupler

The Servo Coupler needs 2 holes drilled and tapped to M3. Optionally you can cut a 2mm x 6mm slot to pass wires from the camera plate down below the bearing plate.:

Assembly

On the Camera Mount pivot use the two Nylon M3 screws cut down so that they tighten against each other without jamming the pivot points.

Upper unit assembly

Lower unit assembly

A Video Sample

See Also

Project 3D Print Files

The following are the 3D print ZIP files used in this specific build. For more versions and information, please see my Thingiverse postings here:
Mark_q Thingiverse Designs

• Project Layout Drawings
• Project STL Files
• New Servo Coupler STL file
• Thingiverse - Heavy Duty Pan & Tilt

Where to buy the parts

• For the bearing and servo coupler -

In the US - ServoCity

In Europe - StepLab

• For the GWS S125-1t 25t servo -

Global - GWS S125-1t Servo

Comments? Questions?

• email me!