NASA GRC Solicitation: Development of Replicate Apollo Roving Vehicle Wheels
Synopsis – Dec 01, 2006
Draft Document – Posted on Dec 01, 2006
General Information
Solicitation Number: NNC07179546L
Posted Date: Dec 01, 2006
FedBizOpps Posted Date: Dec 01, 2006
Original Response Date: Dec 15, 2006
Current Response Date: Dec 15, 2006
Classification Code: A — Research and Development
NAICS Code: 541710 – Research and Development in the Physical, Engineering, and Life Sciences
Contracting Office Address
NASA/Glenn Research Center, 21000 Brookpark Road, Cleveland, OH 44135
Description
This notice is issued by the NASA/GRC to post a Draft Statement of Work via the internet, and solicit responses from interested parties. This document is for information and planning purposes and to allow industry the opportunity to verify reasonableness and feasibility of the requirement, as well as promote competition. Prospective Offerors are invited to submit written comments or questions to: Richard Amiot, no later than 12/15/2006. When responding, reference NNC07179546L and ‘Development of Replicate Apollo Lunar Roving Vehicle Wheels’.
ORAL COMMUNICATIONS WILL NOT BE ACCEPTED REGARDING THIS POSTING. Comments may be forwarded to Richard Amiot via electronic transmission or by facsimile transmission.
THIS IS NOT A NOTICE OF SOLICIATION. IT IS A REQUEST FOR INFORMATION (RFI) ONLY. Submittal Instructions:
I. Please send relevant literature and information to: E-mail address: Richard.W.Amiot@nasa.gov or Fax: (216) 433-5489.
II. NASA is interested in receiving detailed comments on the requirements and design concepts. NASA is also interested in: identifying any areas that might generate unusual issues and if this effort can be accomplished under a fixed price contract.
Other questions of interest:
- What are the engineering characteristics of the LRV wheel that relate to traction, motion resistance, and wear performance in soft soil?
- What measurements should be made to determine the appropriate engineering characteristics of the prototype Apollo LRV wheels?
- How could measurements be made without damaging the prototype wheels?
- Would it be useful to make computer model of the wheel? If so, why, and what types of models. What software package(s) would be used? How would the models be built? What methods of analysis would be employed?
- What is your hypothesis regarding how the original LRV wheel carcass was woven? How could the wire-mesh carcass be woven today?
- What are the major challenges associated with this effort?
- 7 What is the approximate cost of this work?
III. All comments, including those to the System Requirements and Design Concepts, included as an attachment to an emailed response shall be in either Microsoft Word, or PDF format. As part of your information package, please include company Technical Point(s) of Contact including address, telephone number and e-mail address.
IV. Comments received from the RFI will be considered to be proprietary if they are marked as such. Those wishing to keep their responses confidential should state so at the beginning of their response with such wording as “Confidential or Limited distribution. Please do not disclose outside of the US Government.” V. At its discretion, NASA may request further discussions and/or clarification of the information submitted. If agreeable to both parties, such discussions may take place via teleconferencing or on-site visit to NASA Glenn Research Center in Cleveland, Ohio at the responder’s expense. If they do occur, discussions will be constrained to a two hour time duration, and will consist of vendor presentations and subsequent discussions of the presented material only. Representatives from the United States Government Agencies and its contractors may be present for such discussions.
This presolicitation synopsis is not to be construed as a commitment by the Government, nor will the Government pay for the information submitted in response. Respondents will not be notified of the results. An ombudsman has been appointed — See NASA Specific Note “B”.
The solicitation and any documents related to this procurement will be available over the Internet. These documents will reside on a World Wide Web (WWW) server, which may be accessed using a WWW browser application. The Internet site, or URL, for the NASA/GRC Business Opportunities home page is http://prod.nais.nasa.gov/cgi-bin/eps/bizops.cgi?gr=D&pin=22 .
It is the Offeror’s responsibility to monitor the Internet cite for the release of the solicitation and amendments (if any). Potential Offerors will be responsible for downloading their own copy of the solicitation and amendments, if any.
Any referenced notes may be viewed at the following URLs linked below.
Point of Contact
Name: Richard W Amiot
Title: Contract Specialist
Phone: (216) 433-6836
Fax: (216) 433-5489
Email: Richard.W.Amiot@nasa.gov
I. INTRODUCTION
The NASA Glenn Research Center (GRC) in Cleveland, Ohio is currently working to design and evaluate wheels for future lunar roving vehicles (LRVs). For the purpose of establishing a rational baseline to compare with new wheel designs, NASA GRC would like to replicate and test the wire mesh LRV wheels used on the Apollo 15, 16, and 17 missions.
The data acquired from wheel-soil traction / motion resistance testing of the replicate wheels would enable comparative analysis of new wheel geometries and tread patterns. Similarly, wear testing would set the basis for new wheel carcass materials and construction techniques. Moreover, this effort will help NASA gain in-house knowledge of how to manufacture wheels of this type for future lunar missions.
Very little information exists about the techniques used to construct the original LRV wheels; however there are some prototypes that could be examined. For example, there are four wheels on the Apollo LRV Qualification Unit and another spare wheel on display at the Smithsonian National Air and Space Museum (NASM).
We seek vendors that will examine prototype Apollo LRV wheels, replicate them according to our specifications and the information determined from examining the originals, and then verify the engineering characteristics of the replicates. The government will make the arrangements for the contractor to examine the Apollo wheels at the NASM, or elsewhere.
II. METHOD OF PROPOSAL EVALUATION
The government will evaluate the proposals received, based on the requirements stated in section IV. Proposals that do not meet the requirements will not be considered. The remaining proposals will be evaluated based on the following categories.
1. The proposed plan to assess the original Apollo LRV wheel geometry, construction, and engineering characteristics to generate information that could improve the accuracy of the replicate wheels, with respect to their traction performance, motion resistance, and wear characteristics in soft soil.
2. The proposed method to construct the replicate wheels.
3. Cost.
III. DESCRIPTION OF THE ORIGINAL LUNAR ROVING VEHICLE WHEELS
A photograph of the LRV wheel and a summary of the materials used in its construction are provided in Figure 1 and Table 1, respectively. The rim was spun out of 2024 aluminum, the carcass was hand woven with 800 strands of zinc coated high-carbon steel piano wire (each strand was 81.3 cm long by 0.813 mm in diameter), and the bump-stop (the stiff inner frame which prevents the carcass from over-deflecting) was built from titanium. Tread was constructed with titanium strips, riveted to the wheel carcass in a chevron pattern. The tread covered roughly 50% of the ground contact area.
The wheel geometry and deflection characteristics are explicated by Table 2 and Figure 2. The outer diameter of the carcass was 82.2 cm and the maximum wheel width was 22.6 cm. In total, the wheel contained only 5.4 kg of mass. Nominally, the wheel supported 171 kg (in addition to its own weight) on the Apollo 15 mission. Thus, in the lunar gravity 288.5 N of normal-force was distributed over the ground patch under each wheel, under steady-state conditions. The table provides the radial spring rate in three stages; from 0 – 3.81 cm of deflection the spring-rate was 5,837 N/m, from 3.81 – 7.62 cm of deflection the spring-rate was 9,923 N/m, and for deflection greater than 7.62 cm the spring-rate was 106,330 N/m. The large increase in spring-rate at 7.62 cm was due to the carcass coming into contact with the titanium bump-stop. The spring-rate data reported in the table is in conflict with reports from other sources. As such, all of the data available is plotted together in Figure 3, for comparison. A closer view of the data about the nominal normal-load is provided in Figure 4. Analysis of the figure reveals that under nominal loading conditions (on a hard-flat surface), the LRV wheel carcass deflected somewhere in the range from 4.5 – 6.0 cm.
The hand-weaving process used to create the LRV carcass is not well documented. However, the picture in Figure 5 shows the wheel in a fixture and the wire mesh carcass being formed. The piano wire mesh is manufactured in such a way that there are no seams in the carcass. NASA GRC has measurements of the wire mesh spacing and wire angles at discrete locations around the wheel. These data will be included in the statement of work accompanying the request for proposals.
